# Porting the 361 Big Bore



## blsnelling (Jan 6, 2009)

Tonight I began the process of porting the 361BB prototype that I have. The P&C look as good as new upon disassembly. The goal of this saw is to be competetive at a GTG level. It will also be used as a firewood saw. I took measurements on the saw tonight and will post them here. I would appreciate any feedback you guys might have on what numbers I should go with. Here's where it stands right now.


Squish = .017, no base gasket. That's how I've been running it.
Compression was 185 cold after only a little run time. I forgot to check it tonight.
Exhaust 105*
Transfers 125*
Intake 71*
Blowdown 20*
Exhaust width 1.00", can go to 1.25".
Intake width 1.03", can go to 1.25".

The exhaust seems aweful low, but this saw 4-stroked out to15,800. If I went to 98*, I would have to raise the roof .075"! To get to 95* would require raising it .115"! I can't imagine taking that much out. What numbers would you go with?

The exhaust port shape is pretty nice the way it is. The intake floor is very round. A lot of improvement to be made there. As you can see, I've got room to widen quite a bit, nearly .250" on both sides. 

Whatcha think?

Exhaust Port









Intake Port








Crown after running 15,800.


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## blsnelling (Jan 6, 2009)

I need a new circlip to put this thing back together. Getting a OEM Stihl part would be fastest. What saw has an .432" wristpin and uses a .040" thick wire circlip? The OEM 361 circlip uses only .030" thick wire.


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## super3 (Jan 6, 2009)

So much for coating the piston huh?


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## blsnelling (Jan 6, 2009)

super3 said:


> So much for coating the piston huh?


I have to assume that the coating is only for break-in. It wears off right away.


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## blsnelling (Jan 6, 2009)

How about these for numbers? Do these look good for a torqey GTG saw?

Exhaust 100* / Duration 160*
Transfers 120* / Duration 120*
Intake 75* / Duration 150*
Blowdown 20*

Or would you leave the tranfer timing alone for a longer blowdown of 25*?


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## epicklein22 (Jan 6, 2009)

Wasn't this thread in the Hot Saw section? Hopefully some of regular mod guys come and give you answers about the durations. You know most of the people here are in the dark when it comes to modding. Me included.


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## Lakeside53 (Jan 6, 2009)

blsnelling said:


> I have to assume that the coating is only for break-in. It wears off right away.




Why would you need a coating for "break-in"? The RVR of a modern cylinder is correct when made, and the piston isn't supposed to wear except over a long time. Only the rings bed slightly. 

Moly-coating is supposed to prolong the life of the pistion... and stop the skirts skirts wearing. Is it advertised as moly-coated, or what do they call it?

Your pic of the intake port: 
Is it just the pic or do you have a bunch of vertical wear lines? And.. that "crosshatch" looks "odd", almost like it was done with hand held hone, and not carefully. It is hard to get a decent pics of the crosshatch as the lighting tend to pic up on only a few surfaces, but compare it to your oem.


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## timberwolf (Jan 6, 2009)

If the coating is a thou thick as soon as it's gone your already starting to eat away and having a nice tight fitting piston.

Skirts are showing quite a bit of wear low on the skirts both front and back. This is odd for a saw with little time on it.

The bore looks very rough and there is something odd about the placement of the pulse inlet.


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## epicklein22 (Jan 6, 2009)

Lakeside53 said:


> Why would you need a coating for "break-in"? The RVR of a modern cylinder is correct when made, and the piston isn't supposed to wear except over a long time. Only the rings bed slightly.
> 
> Moly-coating is supposed to prolong the life of the pistion... and stop the skirts skirts wearing.



When you gonna try the prototype 441 BB kit for Baileys? I think you would be an excellent candidate to help get these kits perfect.:greenchainsaw:


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## blsnelling (Jan 6, 2009)

timberwolf said:


> If the coating is a thou thick as soon as it's gone your already starting to eat away and having a nice tight fitting piston.
> 
> Skirts are showing quite a bit of wear low on the skirts both front and back. This is odd for a saw with little time on it.
> 
> The bore looks very rough and there is something odd about the placement of the pulse inlet.



Do you have any suggestions on the port timings?


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## Lakeside53 (Jan 6, 2009)

blsnelling said:


> I need a new circlip to put this thing back together. Getting a OEM Stihl part would be fastest. What saw has an .432" wristpin and uses a .040" thick wire circlip? The OEM 361 circlip uses only .030" thick wire.



None that I'm aware of... My packets of clips around that size are all the same wire. Maybe Husky?


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## Lakeside53 (Jan 6, 2009)

epicklein22 said:


> When you gonna try the prototype 441 BB kit for Baileys? I think you would be an excellent candidate to help get these kits perfect.:greenchainsaw:




lol...


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## blsnelling (Jan 6, 2009)

Lakeside53 said:


> None that I'm aware of... My packets of clips around that size are all the same wire. Maybe Husky?



Thanks Andy. I'll give Gregg a call.


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## spacemule (Jan 6, 2009)

epicklein22 said:


> When you gonna try the prototype 441 BB kit for Baileys? I think you would be an excellent candidate to help get these kits perfect.:greenchainsaw:



It'd be fun watching Andy turn gray overnight.


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## Lakeside53 (Jan 6, 2009)

Better hurry - looking like bald before gray...:greenchainsaw:


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## 056 kid (Jan 6, 2009)

Lakeside53 said:


> None that I'm aware of... My packets of clips around that size are all the same wire. Maybe Husky?




i spent tooo much time earlier looking for one of thoes stupid clips. 


You know usually when you loose a snap ring or anything of the type, there is a little "tingg" when it lands. There was no sutch noise so i looked where ever there was soft material except my jacket which was at arms length. i figured that i went pretty far. 

it was chillen on my jacket which i was just about to yank up and vacate due to anger. Lucky i saw it!


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## blsnelling (Jan 6, 2009)

Exhaust 100* / Duration 160*
Transfers 120* / Duration 120*
Intake 75* / Duration 150*
Blowdown 20*

Well, these are the numbers I'm going, I mean have gone with, lol. The intake and exhaust are done. I still have to do the transfers and piston.

A lot of you guys have been asking about porting. I'm no expert, but here's what I do. 


Begin by measuring compression, squish, and port timing. That's a whole topic in itself that I'm a total rookie at. I can get the job done, but that's about it.
.020" is the general rule of thumb for safe squish. The larger the saw, the greater the squish will need to be. For example my 260 is at .015" and my 084 at .021". No signs of detonation or errosion.
I take both the intake and exhaust as wide as the piston skirts will let me. You have to watch out for ring end locations as well. There must by cylinder wall for the ring end to ride on as it goes past the port window.
Port shape is very important. Make the sides of the intake and exhaust straight. Make the roof of the exhaust and floor of the intake "flattish", but make sure there's a slight radius so that the ring is tucked back in gently and dooesn't snag. Put the piston in the cylinder and check your work. The port should close from the sides to the center. The floor of the exhaust and roof ot the intake are not that critical since that's not where flow initiates.
I angle the back of the rear transfers back towards the intake side and clean them up in general.
Most Pro Stihls have a lower transfer intake that I taper all the way to the bottom of the jug. The 361 doesn't have those so you won't be seeing them here.
Put a radius bevel on the edge of all ports. This is critical so as to not catch a ring and destroy your work.
Port and flow the windows in the piston. Create angles that promote flow from the inside of the piston to the outside. A lot of material can be removed, but take care not to hurt the structural integrity of the piston.
Port match the exhaust gasket, heat shield, and muffler inlet.
Mod the muffler such that total exhaust oulets is between 125%-150% of the area of the exhaust port at the cylinder wall.

I'm sure I'm missing some stuff here, but you should get the general idea.

Here's some pics of the 361BB in progress.

Intake Before and after. Notice that I use tape as the guide for where I will port to.








Port finished but not beveled.





I wanted to raise the exhaust port .055" for a 5* change. I cut tape that wide and laid it along the port edge. 








I laid another piece under it that I used as a porting guide. You may notice that I took more off one side than the other. That was by design to leave plenty of room for the ring end to ride on.





Here's a shot to give you an idea how much material I removed at the flange. Notice that I did not lower the floor at all. The scribed line is from my previously modded heat shield.





Exhaust port finished and the piston installed to check for a slight radius as it closes.


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## blsnelling (Jan 6, 2009)

Notice the straight sides. Again, this port has not yet been beveled.


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## 056 kid (Jan 6, 2009)

dank!


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## Martinm210 (Jan 6, 2009)

Awesome work, thanks for all the great tips. I was trying to figure out a way to check skirt clearance, never thought to mark on the piston itself..nice!

Also wasn't sure on the best way to guide/mark inside the cylinder, I tried a pencil, but that wasn't very precise, tape is a good idea too.

I also didn't think about the ring gap.

Any tips on or pics of the cutting tools you're using, looks like some sort of die grinder followed up with some needle files/hand work for smoothing?

Good stuff..


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## Martinm210 (Jan 6, 2009)

Also any general timing numbers or guides? I think I figured out how to figure out what timing I have, but I'm lost as to what I should be looking for.

I know it's all pretty complex how it works, but I like the rules of thumb or guides..gives newbs like me a chance to try and understand...


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## blsnelling (Jan 6, 2009)

Martinm210 said:


> Any tips on or pics of the cutting tools you're using, looks like some sort of die grinder followed up with some needle files/hand work for smoothing?


I use a double-cut, cylinder radius tipped carbide burr in a Dremel, 1/8" shank, 1/4" cutter. Use a ball shaped stone to bevel the port edges.



Martinm210 said:


> Also any general timing numbers or guides? I think I figured out how to figure out what timing I have, but I'm lost as to what I should be looking for.
> 
> I know it's all pretty complex how it works, but I like the rules of thumb or guides..gives newbs like me a chance to try and understand...



Timing rule of thumb, leave timing stock. That's how most of my saws are and it works well on them. This BB cylinder is the first time I ever raised an exhaust port like that.



I put the P&C back on the saw to check a couple things. The exhaust is at exactly 100* as I planned. Woohoo. Like I said, this was the first time I drastically changed port timing. Somehow I managed to get a couple degrees out of the intake so it's at 73* now. I'm happy with that. I didn't think I could get that with that little passage in the way. All that's left are the transfers. Then need to go up to about 120* or I'm likely to be starved for fuel at high RPMs and it then wouldn't hold RPMs at the top.

Here are a couple shots of the piston. Nothing pretty, but it'll flow a lot better. Lighter is good too when you're turning more RPMs.


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## rbmopar (Jan 6, 2009)

Thanks Brad for taking the time too show us how you do your porting. It looks like a safe approach for a rookie like me. So few people will give specifics about thier porting because they either race, or they do it for a bussiness. It is appreciated by alot of folks on here.


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## volks-man (Jan 6, 2009)

rbmopar said:


> Thanks Brad for taking the time too show us how you do your porting. It looks like a safe approach for a rookie like me. So few people will give specifics about thier porting because they either race, or they do it for a bussiness. It is appreciated by alot of folks an here.



:agree2:
thanks!


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## Lakeside53 (Jan 7, 2009)

blsnelling said:


> Here are a couple shots of the piston. Nothing pretty, but it'll flow a lot better. Lighter is good too when you're turning more RPMs.



Can you use the OEM pin to loose more weight?


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## brncreeper (Jan 7, 2009)

Brad, could you post a pic of your porting tools, bits, dremel, and holding vice/stand?


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## parrisw (Jan 7, 2009)

Hey, Brad, really nice work. How do you accurately cut and measure the tape to .055"


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## mtfallsmikey (Jan 7, 2009)

Very educational!!....Kudos to Andy and Brad!!!

:agree2: :agree2:


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## UK heartwood (Jan 7, 2009)

+1 great pics just what I needed to get started.


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## blsnelling (Jan 7, 2009)

Lakeside53 said:


> Can you use the OEM pin to loose more weight?



Absolutely. I used the BB pin the first time round. I'll have to post a shot to show the difference.



brncreeper said:


> Brad, could you post a pic of your porting tools, bits, dremel, and holding vice/stand?


I can. Nothing but a cable drive Dremel and a chainsaw file. No vise, no fancy tools.



parrisw said:


> Hey, Brad, really nice work. How do you accurately cut and measure the tape to .055"


I just set my caliper to .050, marked it, and cut it. If it was off a hair it wouldn't matter much. It takes about .011" for each degree. I wasn't worried about ending up at 99*. It turned out dead on though.


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## Lakeside53 (Jan 7, 2009)

mtfallsmikey said:


> Very educational!!....Kudos to Andy and Brad!!!
> 
> :agree2: :agree2:



HUH? Nothing I did here was praiseworthy:greenchainsaw:


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## spacemule (Jan 7, 2009)

Lakeside53 said:


> HUH? Nothing I did here was praiseworthy:greenchainsaw:



He meant to say spacemule.


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## mtfallsmikey (Jan 7, 2009)

Sorry...BF


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## blsnelling (Jan 7, 2009)

The cylinder is done. This is the first time I did much work to the transfers. I hesitate to even show them. I don't really have the proper tools. I do not have a right-angle grinder. Instead, I had to use a cutoff wheel and a round semi-soft wheel about 1/4" thick. They're not pretty, but it's better than I was afraid they might be. I think they'll flow fine. Notice how I brought the rear transfer back towards the intake more.


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## 056 kid (Jan 7, 2009)

I dosent look like you did it with a cut off wheel!!!! it looks pretty drn good!


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## FELLNORTH (Jan 7, 2009)

Are You Working Over The Crankshaft As Well. I'm Not Real Specialized In Small Engines ( I Normally Play Car Stuff ) But Taking Weight Off The Piston And Wrist Pin Will Create An Imbalance In Your Engine, And At 14k That Cant Be Good.


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## blsnelling (Jan 7, 2009)

056 kid said:


> I dosent look like you did it with a cut off wheel!!!! it looks pretty drn good!



I finished with the semi-soft 1/4" wheel. I have no idea what it is, just glad I had it. I need order a bunch of different stuff from McMasterCarr and then I'll know what I want to reorder in the future.


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## FELLNORTH (Jan 7, 2009)

beautiful portwork by the way, that cant be easy, i have a hard enough time with intake port of a small block ford....


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## blsnelling (Jan 7, 2009)

The porting work is done. I'm just waiting on the circlips from Gregg. I believe he dropped them in the mail yesterday. Unfortunately, that's on the west coast. So it'll probably be next week before I get to satisfy my curiosity as to the results


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## timberwolf (Jan 8, 2009)

Ports look good.



> But Taking Weight Off The Piston And Wrist Pin Will Create An Imbalance In Your Engine, And At 14k That Cant Be Good.



Unlike a multi cylinder engine, a two stroke single can not be balanced, at least not without some sort of counter shaft/weight. 

lowering the weight of the piston will only reduce the inherant imbalance a little. The horizantal imbalance created by the crank bells moving weight front to back will be the same, the vertical imbalance will be reduced though as the piston weight will be lower and as the crank bells only balance about half the piston weight there will be less net imbalance in the up down direction.


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## blsnelling (Jan 8, 2009)

timberwolf said:


> Ports look good.



That's good to hear considering it was the first time I really hacked on some transfers. 

"Oh where oh where can my circlips be, oh where oh where can they be...."


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## teacherman (Jan 8, 2009)

Brad, you are braver than I. I would like to someday play with a cylinder and piston, but I have no idea what to do. Maybe one of te older 026s can be turned into a hotsaw for practice purposes. Oh by the way, IMPRESSIVE WORK!


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## Taxmantoo (Jan 8, 2009)

FELLNORTH said:


> beautiful portwork by the way, that cant be easy, i have a hard enough time with intake port of a small block ford....



There's a tradeoff between vertical and horizontal balancing. 
For example, let's take one extreme, where the crank is balanced by itself. When you hook up a piston to that crank, you will get a terrible vertical vibration. 

Now let's take the other extreme, we'll counterweight the crank until the vertical shake is gone. Now we've got a horizontal shake that's as bad as the vertical shake was in the first example. 

The way it works in real life is that the crank counterweights on a single cylinder engine partially balance the piston and connecting rod, striking a compromise between vertical and horizontal shake. If you make the piston lighter without changing anything else, all it does is lessen the vertical shake, no harm in that. If you take weight off both the piston and the counterweight, then both vertical and horizontal vibes go down a bit.


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## blsnelling (Jan 8, 2009)

The bottom line is, it doesn't really matter on a chainsaw. Take a saw like the Dolmar 6400/7300/7900. They're all identical except piston size. Same crank, same everything. Just pistons of three different weights. IMHO, lighter is better when you're looking to turn more RPMs.


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## timberwolf (Jan 8, 2009)

> then both vertical and horizontal vibes go down a bit.



Horizantal will go down, but vertical will go up less than it would if piston was left alone, but still more than if the piston was lightened and crank left alone, This as the piston mass is not being fully offset. If the crank is lightened vertical can not be less unless the piston were lightened more than ~ twice that same amount.

I have put some big pistons on smaller saws and going 4-6mm over stock things get shaky. Noticable if you put the saw on a cement floor at idle and it will hop around like a rabbit on 3 cans of Redbull.


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## FELLNORTH (Jan 8, 2009)

hey thanx guys


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## scotclayshooter (Jan 9, 2009)

Martinm210 said:


> Awesome work, thanks for all the great tips. I was trying to figure out a way to check skirt clearance, never thought to mark on the piston itself..nice!
> 
> Also wasn't sure on the best way to guide/mark inside the cylinder, I tried a pencil, but that wasn't very precise, tape is a good idea too.
> 
> ...





I thought this was a neat idea posted by Timberwolf using a stack of piston rings pushed in with the piston 



Timberwolf said:


> Have you made up a port map? Thats about the easiest way to keep track of port heights.
> 
> As far as getting the height, I like to cut a notch in the center of the port to the height I want then work out to the sides. A stack of used rings can be pushed in with piston to give a reference line also.


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## blsnelling (Jan 9, 2009)

scotclayshooter said:


> I thought this was a neat idea posted by Timberwolf using a stack of piston rings pushed in with the piston



I didn't use a stack of rings, but I did use the piston to push one of the rings squarely into the bore to help me keep all the transfers square and even. Excellent tip Brian. Thanks.


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## Wet1 (Jan 10, 2009)

Yet another excellent writeup on porting Brad! Gotta bump this back TTT...


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## blsnelling (Jan 10, 2009)

Thanks. I was hoping to get the circlip today but did not. I'm anxious to get it running. Instead I spent the day cleaning up my latest acquisition, a 041 Super to go with the 076 Super.


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## Austin1 (Jan 11, 2009)

blsnelling said:


> The cylinder is done. This is the first time I did much work to the transfers. I hesitate to even show them. I don't really have the proper tools. I do not have a right-angle grinder. Instead, I had to use a cutoff wheel and a round semi-soft wheel about 1/4" thick. They're not pretty, but it's better than I was afraid they might be. I think they'll flow fine. Notice how I brought the rear transfer back towards the intake more.


How do you get the photo's to work out so good?
I have been up all night working on my 2152 and took some pic's and all I get is a silver blur I have two 100 watt light bulbs above my work bench plus the garage lights. But cant seem to figure out how to turn my flash off unless I go out during daylight I tried the macro setting as well.
Saw is all together but as luck would have it I am out of Oxygen for the torch so the Muffler will have to wait till Monday night.


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## blsnelling (Jan 11, 2009)

I'm using a DSLR. Try backing up a little so that it can focus.


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## Martinm210 (Jan 11, 2009)

FYI,

Here is a good link someone pointed me toward.

This is a good couple of pages on cylinder mapping, only difference is we only have to work from the bottom and don't have as many ports to work with.

http://www.macdizzy.com/cylinder_map.htm

He does point out here when measuring port area, that it's not necessarily the opening along the cylinder wall that's important so much as the area of the port running along the channel:

http://www.macdizzy.com/cylinder_map2.htm

This would indicate the importance of opening back into the channels as best as we can.

Anyhow, I thought it was a pretty cool idea how he left the port map taped into a cylinder, then stuck the piston down in there and measured the port width at the angles they come in using the flaps of paper to simulate the angles.











The only bad part is that in the end he used software to do some calculations on the port areas to predict performance. I havn't searched very hard, but it would be great if there were some freeware tools for this to play with.


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## Austin1 (Jan 11, 2009)

blsnelling said:


> I'm using a DSLR. Try backing up a little so that it can focus.


I am using a little pocket camera fuji 340, I found my manual so now I know how to turn the flash off as all the little syboils on the camera are worn off. I had wanted to show how easy the transfers were to get at on this saw, it's the same as my 2159.I was able to take pics of things that were dull in colour but taking pics of metallic shiny objects were impossible


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## Martinm210 (Jan 11, 2009)

Austin1 said:


> I am using a little pocket camera fuji 340, I found my manual so now I know how to turn the flash off as all the little syboils on the camera are worn off. I had wanted to show how easy the transfers were to get at on this saw, it's the same as my 2159.I was able to take pics of things that were dull in colour but taking pics of metallic shiny objects were impossible



Yeah, uou just need to stick some sort of bright light to light everything up consistently. It's dynamic range that you're fighting. A camera can only capture something on the order of 5 stops worth of dynamic range, when the visible eye can see up to 12 stops worth (completely black to white). This is why people use flash in bright outdoor conditions, it's to fill in the dark spots the camera has trouble capturing.

In the case of macro or close up type shot. Shiny objects are always tricky, but even more of a problem is the flash. Most cameras struggle metering flash appropriately for anything closer than a few feet away, and shiny objects are just simply hard to avoid overexposure on with flash.

A DSLR and using a raw program to correct for overexposure can usually help with this. It gives you about a 1 stop cushion to capture information either way that would otherwise be lost.

Anyhow good stuff here on the porting, some great general guidlines.


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## parrisw (Jan 11, 2009)

Martinm210 said:


> Yeah, uou just need to stick some sort of bright light to light everything up consistently. It's dynamic range that you're fighting. A camera can only capture something on the order of 5 stops worth of dynamic range, when the visible eye can see up to 12 stops worth (completely black to white). This is why people use flash in bright outdoor conditions, it's to fill in the dark spots the camera has trouble capturing.
> 
> In the case of macro or close up type shot. Shiny objects are always tricky, but even more of a problem is the flash. Most cameras struggle metering flash appropriately for anything closer than a few feet away, and shiny objects are just simply hard to avoid overexposure on with flash.
> 
> ...



Good write up. This is what makes these good to have. But are kinda spendy.


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## blsnelling (Jan 11, 2009)

I would so love to have a ring flash!!!!!!!!!!!!!!!


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## parrisw (Jan 11, 2009)

blsnelling said:


> I would so love to have a ring flash!!!!!!!!!!!!!!!



Yup, they sure are nice. But then you need a nice Macro lens to go with it, which is also kinda spendy!!!! I've already got too much invested into my DSLR, ahhh, whats another $1000


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## blsnelling (Jan 11, 2009)

I take 99.9% of my pics with a 24-105L IS lens. That's 90% of the picture quality right there. Good light is always a challenge. I really should get a good macro lens for all the closeup shots I'm always taking. The big DSLR sensor fights you though with a much more shallow field of view. A guy really needs to use a tripod and small aperature to get good pics of the work we do.


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## Urbicide (Jan 11, 2009)

Austin1 said:


> How do you get the photo's to work out so good?
> I have been up all night working on my 2152 and took some pic's and all I get is a silver blur I have two 100 watt light bulbs above my work bench plus the garage lights. But cant seem to figure out how to turn my flash off unless I go out during daylight I tried the macro setting as well.
> Saw is all together but as luck would have it I am out of Oxygen for the torch so the Muffler will have to wait till Monday night.



How about a piece of electrical tape over the flash?


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## parrisw (Jan 11, 2009)

blsnelling said:


> I take 99.9% of my pics with a 24-105L IS lens. That's 90% of the picture quality right there. Good light is always a challenge. I really should get a good macro lens for all the closeup shots I'm always taking. The big DSLR sensor fights you though with a much more shallow field of view. A guy really needs to use a tripod and small aperature to get good pics of the work we do.



Dang that's a nice lens. I don't have any L series lens's. Too much $$ for me. I can do pretty good with what I got. With all my saw photos, I usually get lazy and just use my Canon A720is


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## blsnelling (Jan 12, 2009)

I often think it would be easier with a point and shoot in macro mode. The smaller sensor gives a much greater depth of field, leaving everything in focus.


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## parrisw (Jan 12, 2009)

blsnelling said:


> I often think it would be easier with a point and shoot in macro mode. The smaller sensor gives a much greater depth of field, leaving everything in focus.



Yes, that's why I use it. The macro functionality is much better, easier to use, better results, but if you have a full setup for macro for your DSLR then use that, but I don't. Maybe, my next build, I'll break out the SLR and try it, I've actually never used it to shoot my saws.


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## Lakeside53 (Jan 12, 2009)

Higher F stop is key to depth of focus when using macro or closeup lenses. Flash can be difficult to aim correctly when looking inside of bores etc.

The smaller 1/2 frame sensors increase the efective focal length of the DSLR lenses, which decreases depth of focus. Example.. my 100mm macro is actually 150 on my DSLR.

I use either a desk halogen (or very bright incandesent with the correct camera setting) and/or a remote handheld flash. And.. a tripod, so i can slow down the shutter speed for higher F stop. For a bore... don't be shy about shining a second or thrid light though inlet, spark hole and exhaust. The secondary light output needs to be balanced with the main source, but that's not hard (dimmer, neutral density filters etc).

Don't be afraid to crank up your camera ISO to gain higher F stops.


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## parrisw (Jan 12, 2009)

Lakeside53 said:


> Higher F stop is key to depth of focus when using macro or closeup lenses. Flash can be difficult to aim correcly when looking inside of bores etc.
> 
> 
> The smaller 1/2 frame sensors increase the efective focal length of the DSLR lenses, which decreases depth of focus. Example.. my 100mm macro is actually 150 on my DSLR.
> ...



Which camera are you using. Wouldn't it be 160mm?? My Canon, I thought the sensor was 1.6x not 1.5x


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## Lakeside53 (Jan 12, 2009)

parrisw said:


> Which camera are you using. Wouldn't it be 160mm?? My Canon, I thought the sensor was 1.6x not 1.5x



150. I only speak Nikon.. it's a Stihl/Husky thing...


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## parrisw (Jan 12, 2009)

Lakeside53 said:


> 150. I only speak Nikon.. it's a Stihl/Husky thing...



ha ha ha LOL. Nikon???? Huuu?? they make cameras?


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## Lakeside53 (Jan 12, 2009)

parrisw said:


> ha ha ha LOL. Nikon???? Huuu?? they make cameras?



And you should be happy -it's what makes canon keep trying to make better cameras


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## parrisw (Jan 12, 2009)

Lakeside53 said:


> And you should be happy -it's what make canon keep trying to make better cameras



Right?? here we go. ha ha. I don't agree.


----------



## Lakeside53 (Jan 12, 2009)

parrisw said:


> Right?? here we go. ha ha. I don't agree.



Like we say to Husky guys that like to beat on stihl -have you ever owed one [pro Nikon]?:greenchainsaw: 

BTW... I have several lenses that make 088's look cheap... :jawdrop:


----------



## Martinm210 (Jan 12, 2009)

Urbicide said:


> How about a piece of electrical tape over the flash?



You can sometimes get good results by cheating a softbox too by using a piece of white paper. One of the problems with shiny objects is the light source coming from one point and it's too powerful and harsh. Try holding a piece of white paper not directly on the flash, but between the lens and the flash point to allow the flash to illuminate that sheet of paper.

This will give you a flashbox diffuser effect and can make a big difference. I do this now and then with my on board flash in when tinkering in the office.

I do have too many camera toys, but a ring flash isn't one of them.... yet.






Cameras was a previous obsession...Had two kids and some 20K clicks later a small arsenal of attachments. At least they hold their value, wish I could say the same for my dirt bikes.

Sold a few lenses, I just like my primes and a good flash anymore.

Sorry about being off topic...


----------



## Lakeside53 (Jan 12, 2009)

Martinm210 said:


> You can sometimes get good results by cheating a softbox too by using a piece of white paper. One of the problems with shiny objects is the light source coming from one point and it's too powerful and harsh. Try holding a piece of white paper not directly on the flash, but between the lens and the flash point to allow the flash to illuminate that sheet of paper.
> 
> This will give you a flashbox diffuser effect and can make a big difference. I do this now and then with my on board flash in when tinkering in the office.
> 
> ...






Hey... that look like my shelf!!!! except... they are all Nikon and I also have the ring flash


----------



## Martinm210 (Jan 12, 2009)

Back to porting...here is another excellent link. I think I found reading material for a couple of weeks, going to have to build a spreadsheet to play with some of the tools in there though.

http://www.edj.net/2stroke/jennings/

Special thanks to rmh3481 for sharing the link, that's good stuff.


----------



## Martinm210 (Jan 12, 2009)

Lakeside53 said:


> Hey... that look like my shelf!!!! except... they are all Nikon and I also have the ring flash



Darn...note to wife...Ring flash for next Christmas!!...lol!


----------



## parrisw (Jan 12, 2009)

Lakeside53 said:


> Like we say to Husky guys that like to beat on stihl -have you ever owed one [pro Nikon]?:greenchainsaw:
> 
> BTW... I have several lenses that make 088's look cheap... :jawdrop:



Which one do you have. If you were serious, you'd have a full frame sensor. Doesn't sound like you do.

But for what I do in photography, my setup is plenty. It'll easily do more then my experience will allow, that goes for most people actually.


----------



## parrisw (Jan 12, 2009)

Man this is really getting off topic.


----------



## Austin1 (Jan 12, 2009)

parrisw said:


> Man this is really getting off topic.


HaHa And I started it:hmm3grin2orange:


----------



## blsnelling (Jan 12, 2009)

parrisw said:


> Man this is really getting off topic.



Nahhh. Have to be able to take pics of the port work


----------



## parrisw (Jan 12, 2009)

blsnelling said:


> Nahhh. Have to be able to take pics of the port work



Ok, I do enjoy photography though.


----------



## Lakeside53 (Jan 12, 2009)

parrisw said:


> Which one do you have. If you were serious, you'd have a full frame sensor. Doesn't sound like you do.
> 
> But for what I do in photography, my setup is plenty. It'll easily do more then my experience will allow, that goes for most people actually.



That's very true for almost everyone!

Full frame sensors are nice but have little practical effect on my work other than messing up the low end of my 17-35 F2.8 A full frame sensor is in my future, but the dow needs to be back over 12k again, or I sell my 088


----------



## Wet1 (Jan 12, 2009)

parrisw said:


> Which one do you have. If you were serious, you'd have a full frame sensor. Doesn't sound like you do.
> 
> But for what I do in photography, my setup is plenty. It'll easily do more then my experience will allow, that goes for most people actually.



And give up sensor density and the crop factor? I still see both formats as having their place.

Oh yeah, another vote for Nikon!

BTW, for you guys wanting a dedicated macro lens but don't want to fork out the $, look into a Canon 500D. It works like a filter that can be screwed onto the end of a telephoto lens and converts it to a macro. It's fairly cheap, easy to pack with you, and works well.


----------



## blsnelling (Jan 12, 2009)

I actually prefer my 1.6 crop. I like the long end of the lens more than the short. I just don't have any need to work that wide. I had a 10-22 and sold it.


----------



## parrisw (Jan 12, 2009)

Lakeside53 said:


> That's very true for almost everyone!
> 
> Full frame sensors are nice but have little practical effect on my work other than messing up the low end of my 17-35 F2.8 A full frame sensor is in my future, but the dow needs to be back over 12k again, or I sell my 088



Ya, I'll agree. Full frame is just outa my league.




blsnelling said:


> I actually prefer my 1.6 crop. I like the long end of the lens more than the short. I just don't have any need to work that wide. I had a 10-22 and sold it.



aaahh man. I'm looking for a good deal on a 10-22. Widest I got now is a 17. I really enjoy wide angle photo's. Anybody here tried a lightbox for P&C shots?? I'd llike to make one and try it out. You can get very cool photographs with a lightbox.


----------



## Austin1 (Jan 12, 2009)

Thanks for all the photography tips! although I only get about 30% of it!
I know this went off topic but I learned allot! Thanks guy's!!!
P.S a fancy camera costs as much as say a new 2171!!!! Got my Oxy and the garage is warming up thanks to the wood I cut.


----------



## parrisw (Jan 12, 2009)

Austin1 said:


> P.S a fancy camera costs as much as say a new 2171!!!!



ya, or allot more.


----------



## Tzed250 (Jan 12, 2009)

It wil be a while before the FX sensors are affordable. D3X is $7999 right now. Kinda silly though, if you need full frame any SLR loaded with color slide film will get the job done. Not as convenient, but it save you about $7700!!


----------



## Lakeside53 (Jan 12, 2009)

Tzed250 said:


> It wil be a while before the FX sensors are affordable. D3X is $7999 right now. Kinda silly though, if you need full frame any SLR loaded with color slide film will get the job done. Not as convenient, but it save you about $7700!!



Well.. for an FX sensor based camera.. you are about $6K too high Check out the D700...

http://www.fotoconnection.com/p90133-nikon-d700-121-megapixel-dslr-camera-body-072x-zoom.html


Hmmmm... Sell my 088... scrounge up a couple more $$, and press the "buy-it-now button"..


----------



## parrisw (Jan 12, 2009)

Lakeside53 said:


> Well.. for an FX sensor based camera.. you are about $6K too high Check out the D700...
> 
> http://www.fotoconnection.com/p90133-nikon-d700-121-megapixel-dslr-camera-body-072x-zoom.html
> 
> ...



Nice machine. 

Do you have any online photo albums? That we could look through?


----------



## Lakeside53 (Jan 12, 2009)

Nope.. except for some boring pics of a lathe rebuild.

I do have about 8K images on my laptop, 8k of slides and about 5K of negatives... All that proves is that I'm old.


----------



## parrisw (Jan 12, 2009)

Lakeside53 said:


> Nope.. except for some boring pics of a lathe rebuild.
> 
> I do have about 8K images on my laptop, 8k of slides and about 5K of negatives... All that proves is that I'm old.



ha ha lol. Ya, I don't use any online albums either. All on HD's here.


----------



## Tzed250 (Jan 12, 2009)

Lakeside53 said:


> Well.. for an FX sensor based camera.. you are about $6K too high Check out the D700...
> 
> http://www.fotoconnection.com/p90133-nikon-d700-121-megapixel-dslr-camera-body-072x-zoom.html
> 
> ...



Ooops...forgot about the 700


----------



## Lakeside53 (Jan 12, 2009)

Tzed250 said:


> Ooops...forgot about the 700



If they would just put HD video on that model, I'd have my dream camera...


----------



## Tzed250 (Jan 12, 2009)

Lakeside53 said:


> If they would just put HD video on that model, I'd have my dream camera...



They want you to buy the D90 too...


----------



## Lakeside53 (Jan 12, 2009)

Tzed250 said:


> They want you to buy the D90 too...



Bastads! 

I had my hands on a D90 a week ago.. damn.. nice camera... I'M GETTING WEAKER... I NEED BOTH.... :greenchainsaw:  :greenchainsaw:  :greenchainsaw:


----------



## timberwolf (Jan 12, 2009)

I use a D80 for work, but would love to have a D90 for my own. I'v been sticking a little cash in an envelope for one.


----------



## Tzed250 (Jan 12, 2009)

Yeah, D90, D3x, 200/2.0 300/2.8, 600/4...

They draw the Powerball again on Wednesday...


----------



## blsnelling (Jan 12, 2009)

Time for a little more 361BB talk. I finished putting it together tonight. I filled it with 100LL and fired it up. It idles nicely and throttle response is good. Compression is 175 cold and 165 hot. I'm surprised it's still that high after raising the exhaust 5*, which equals about .055". I only had that one little piece of Poplar left to cut on. Not near enough to do any significant testing. A quick glance at the tach showed it holding >13K in the cut with an aggressive square ground chain. Yet I can push down and lug it and it keeps right on cutting. Looks like it's got a good powerband. Again, I haven't been able to run it enough to know for sure, but it looks like it's going to turn 15,500-15,800 @ WOT. As soon as get a chance to do some testing with the OEM ported 361, I've got some more tricks up my sleeve for the winner. Just a little teaser there for ya. No pics or vids yet. I've got to get a test log to continue.


----------



## volks-man (Jan 12, 2009)

blsnelling said:


> Time for a little more 361BB talk. I finished putting it together tonight. I filled it with 100LL and fired it up. It idles nicely and throttle response is good. Compression is 175 cold and 165 hot. I'm surprised it's still that high after raising the exhaust 5*, which equals about .055". I only had that one little piece of Poplar left to cut on. Not near enough to do any significant testing. A quick glance at the tach showed it holding >13K in the cut with an aggressive square ground chain. Yet I can push down and lug it and it keeps right on cutting. Looks like it's got a good powerband. Again, I haven't been able to run it enough to know for sure, but it looks like it's going to turn 15,500-15,800 @ WOT. As soon as get a chance to do some testing with the OEM ported 361, I've got some more tricks up my sleeve for the winner. Just a little teaser there for ya. No pics or vids yet. I've got to get a test log to continue.



"i see you have constrcted a new light sabre........."

awaiting the vids and timed results.
:yourock:


----------



## blsnelling (Jan 13, 2009)

The trial has been had and the verdict is in. I ran my ported OEM P&C against my ported 361BB tonight. Both saws wore the same 20" bar and round ground Stihl 33RSC chain. Both saws start and run well. One is a clear leader. Which one is itopcorn:


----------



## Peacock (Jan 13, 2009)

Looks good.

Is the chain sharp? It looks like either the depth gauges are too high or the wood is dead, dry locust.

The second saw sounds pretty lean.


----------



## blsnelling (Jan 13, 2009)

Peacock said:


> Looks good.
> 
> Is the chain sharp? It looks like either the depth gauges are too high or the wood is dead, dry locust.
> 
> The second saw sounds pretty lean.



The chain is sharp. It just really hard, dead, frozen wood. I already richened up the 2nd one from the first runs I made. It got stronger. If it's still lean, then there's more in it.


----------



## blsnelling (Jan 13, 2009)

The 2nd and fastest saw is the 361BB. It is very strong in the cut. The runs I've timed here where after I had already richened it up a little. It got faster after doing so. There may be a little more there yet with some timed cuts and fine tuning. The OEM P&C are strong, but no match for the BB. The little secret I was joking about...a MS460 carb. Bolts right on with minimal mods from an initial 1st glance.


----------



## stihlboy (Jan 13, 2009)

who is in the window???


----------



## Taxmantoo (Jan 13, 2009)

2nd saw clearly runs faster out of the wood.
Seems like the times are close enough that if you ported another pair of cylinders, the winner might reverse. OTOH, if the Mahle is fully broken in and the fast one is the BB kit, then that would make the difference more than it seems on the video.

Do they both have the 460 carb?


----------



## blsnelling (Jan 13, 2009)

taxmantoo said:


> Seems like the times are close enough that if you ported another pair of cylinders, the winner might reverse. OTOH, if the Mahle is fully broken in and the fast one is the BB kit, then that would make the difference more than it seems on the video.



The BB is 11% faster. That's significant. The OEM is well broken in where as the BB has only had less than a tank through it. Both have stock carbs at this point. I wanted to compare just the P&C for starters. I'll now continue building the 361BB.


----------



## Lakeside53 (Jan 13, 2009)

Based on the wear we saw in a previous pic, the BB piston is well broken in...


----------



## stihlboy (Jan 13, 2009)

stihlboy said:


> who is in the window???



come on brad who????


----------



## blsnelling (Jan 13, 2009)

stihlboy said:


> come on brad who????



My wife or my 10 year old daughter. Why?


----------



## stihlboy (Jan 13, 2009)

blsnelling said:


> My wife. Why?



it was just one of those things that will bug the crap out of you if you don't know the answer


----------



## stihlboy (Jan 13, 2009)

blsnelling said:


> My wife or my 10 year old daughter. Why?



it was buggin me and i really wanted to know sorry


----------



## blsnelling (Jan 13, 2009)

stihlboy said:


> it was buggin me and i really wanted to know sorry



No problem.


----------



## stihlboy (Jan 13, 2009)

blsnelling said:


> No problem.



the avatar kinda messes with ya, it reminds me of your dad no offense


----------



## blsnelling (Jan 13, 2009)

stihlboy said:


> the avatar kinda creeps me out, it reminds me of your dad no offense



LOL. That made me laugh.


----------



## volks-man (Jan 13, 2009)

*?s*

nice job!
thanks for the vid.
what rpm are the saws turning?


----------



## stihlboy (Jan 13, 2009)

blsnelling said:


> LOL. That made me laugh.



its just every time i see it i invision your dad with that camera just a smilin away


----------



## blsnelling (Jan 13, 2009)

volks-man said:


> nice job!
> thanks for the vid.
> what rpm are the saws turning?



I didn't check tonight. The OEM usually around 15,100. I don't have much time with the BB but will be in the ballpark of 15,500-15,800.


----------



## Lakeside53 (Jan 13, 2009)

WOT doesn't really count..... What are they turning in the cut?


----------



## volks-man (Jan 13, 2009)

blsnelling said:


> I didn't check tonight. The OEM usually around 15,100. I don't have much time with the BB but will be in the ballpark of 15,500-15,800.





Lakeside53 said:


> WOT doesn't really count..... What are they turning in the cut?



the reason i ask is because they really do sound like they are 'screaming'. very high pitched saw sounds! 

lakes question is a good one though. do you record in-cut rpm?


----------



## blsnelling (Jan 13, 2009)

Lakeside53 said:


> WOT doesn't really count..... What are they turning in the cut?



WOT is only an indicator. Doesn't mean much if you raised the exhaust roof and killed compression to get them. I don't really think RPMs in the wood counts either. The BB is faster because I can push on it harder than the OEM. The OEM would stall if I pushed as much as I am on the BB. It just like the 7900 Slingr built. If I don't really load it down, I saw >13K in the cut with a square ground chain in a different log last night.



volks-man said:


> the reason i ask is because they really do sound like they are 'screaming'. very high pitched saw sounds!
> 
> lakes question is a good one though. do you record in-cut rpm?



They are screamin'! But nothing out of line with other modded saws.


----------



## yo2001 (Jan 13, 2009)

How much faster in percentage? The BB kit sounded like its turning some rpm. Good build as usual.


----------



## Lakeside53 (Jan 13, 2009)

He said 11%... not a big gain considering the cc etc. Of couse, I'm not the guy to ask. I could care less if I cut a log in 20 or 22.2 seconds


----------



## Lakeside53 (Jan 13, 2009)

blsnelling said:


> WOT is only an indicator. Doesn't mean much if you raised the exhaust roof and killed compression to get them. I don't really think RPMs in the wood counts either.  The BB is faster because I can push on it harder than the OEM. The OEM would stall if I pushed as much as I am on the BB. It just like the 7900 Slingr built. If I don't really load it down, I saw >13K in the cut with a square ground chain in a different log last night.
> 
> 
> 
> They are screamin'! But nothing out of line with other modded saws.



Actually, the only thing that matters is the rpm in the cut.... What you can maintain at optimal pressure... and that gives the best cut rate and time... 

13k not loaded isn't meaningful... what is it "loaded" and cutting best?


----------



## stihlboy (Jan 13, 2009)

Lakeside53 said:


> Actually, the only thing that matters is the rpm in the cut.... What you can maintain at optimal pressure... and that gives the best cut rate and time...
> 
> 13k not loaded isn't meaningful... what is it "loaded" and cutting best?



na andy it is only if your chain is sharp as demonstrated at the GTG


----------



## Lakeside53 (Jan 13, 2009)

stihlboy said:


> na andy it is only if your chain is sharp as demonstrated at the GTG



Oh sorry.. I forgot about POSERS opcorn:


----------



## stihlboy (Jan 13, 2009)

Lakeside53 said:


> Oh sorry.. I forgot about POSERS opcorn:



excuse me??? are you calling brad a poser????


----------



## windthrown (Jan 13, 2009)

We all know what really matters in the cut! 

Its what oil is in the saw!  :greenchainsaw:


----------



## stihlboy (Jan 13, 2009)

windthrown said:


> We all know what really matters in the cut!
> 
> Its what oil is in the saw!  :greenchainsaw:



gary gravy


----------



## blsnelling (Jan 13, 2009)

windthrown said:


> We all know what really matters in the cut!
> 
> Its what oil is in the saw!  :greenchainsaw:



Why of course. It was Stihl bar oil!!!!! And Klotz R50 @ 40:1 in 100LL.


----------



## yo2001 (Jan 13, 2009)

So what do you think about going 20 deg blowdown on a work saw? In cuts?


----------



## blsnelling (Jan 13, 2009)

yo2001 said:


> So what do you think about going 20 deg blowdown on a work saw? In cuts?



That's exactly what this saw has. Exhaust at 100* and transfers at 120*.


----------



## yo2001 (Jan 13, 2009)

blsnelling said:


> That's exactly what this saw has. Exhaust at 100* and transfers at 120*.


Right. So what you think of it mr.Snelling? Is it much gain? Narrow powerband or broad? I wanted to know the pros and cons if you don't mind.


----------



## blsnelling (Jan 13, 2009)

yo2001 said:


> Right. So what you think of it mr.Snelling? Is it much gain? Narrow powerband or broad? I wanted to know the pros and cons if you don't mind.



There isn't a hint of peakiness in the powerband. You'll notice several different in the cut RPMs in the video I poseted. I was not only looking to see which would yield the fastest times, but also demonstrating how broad the powerband is. It pulls VERY strong. I'm definately impressed.


----------



## blsnelling (Jan 14, 2009)

I just put a 460 carb on the 361BB. It won't idle at all. It's not trying to race like an air leak. It simply won't run that slow and shakes like crazy. Rev it up and it smooths out.

What does the little replaceable jet near the needle valve control? Is that the fixed portion of the high side? I swapped that out with the one from the 361 carb and it got worse. I was only guessing anyway.

I borrowed the choke shaft from the 361 carb to get the correct arm orientation. I had to widen the flat spot for the 460 choke plate to fit in it. I also had to open up the impulse passage and use the bottom plate from the 361 carb. Other than that, it was a direct bolt on. 

So what might be the idling problem and how to fix it.


----------



## Lakeside53 (Jan 14, 2009)

The idling problem may due to way too much gas, or an imbalance in the L circuit (pressures, venturi etc.). The L path to the progression bores in late model HD carbs (361, 460, 290 etc) has a check valve, and it's not replaceable.

You might be better trying an early model 044 carb.


----------



## blsnelling (Jan 14, 2009)

Lakeside53 said:


> The idling problem may due to way too much gas, or an imbalance in the L circuit (pressures, venturi etc.). The L path to the progression bores in late model HD carbs (361, 460, 290 etc) has a check valve, and it's not replaceable.
> 
> You might be better trying an early model 044 carb.



Thanks Andy. This is a HD16 carb. Funny you mention the 044 carb. That's what I put on my 260 and it runs like a dream. No one problem since the first startup with it.


----------



## flyboy (Jan 14, 2009)

Time for a dyno? That would give you all your data and then some.

I bet you could make more $ with this thing then the payments would be.



http://www.land-and-sea.com/kart-dyno/kart-dyno.htm


----------



## Bluemaxpilot (Jan 15, 2009)

Yep time for a Dyno....it's only $99 a month!!!


----------



## Urbicide (Jan 15, 2009)

You would be the only one on the block with one.


----------



## Stihl 041S (Jan 15, 2009)

Bluemaxpilot said:


> Yep time for a Dyno....it's only $99 a month!!!



$99 down,$99 a month for 99 months!


----------



## blsnelling (Jan 15, 2009)

Stihl 041S said:


> $99 down,$99 a month for 99 months!



Why don't you build us one out of stainless or titanium, Rob


----------



## Stihl 041S (Jan 15, 2009)

*Saws are like guns, operater makes a big difference*



blsnelling said:


> Why don't you build us one out of stainless or titanium, Rob


Haven't run a mill or a saw in 5 months. Family matters clear up in 2 weeks and I can have a life again. Like give out Christmas presents. 
Anyway, with dynos, you got to blow the saw up to see what it will REALLY do, otherwise there will always be a question.....................


----------



## blsnelling (Jan 22, 2009)

Here's the results of the bored out carb on the BB vs the OEM ported saw. It had a 11% gain on it before. Thant's now 24% with the best times from both saws. If I average all cuts from both saws it's still a 18.5% gain. I was tweaking the tuning as I made cuts and took the fastest from each saw. The BB seems to like to run a little leaner than the OEM. Enjoy.


----------



## brncreeper (Jan 22, 2009)

flyboy said:


> Time for a dyno? That would give you all your data and then some.
> 
> I bet you could make more $ with this thing then the payments would be.
> 
> ...


Interesting, the torque arm appears to be nothing more than a load cell.


----------



## Cowboy Billy (Jan 22, 2009)

Awesome Brad  Lots of food for thought there. If I thought I could do it and not destroy my saw I would try it:jawdrop: 

Billy


----------



## yo2001 (Jan 22, 2009)

sounds like you can lean on that BB saw pretty hard. Nice work


----------



## volks-man (Jan 22, 2009)

refresh my failing memory. 

is there much difference in the mufflers on the two saws?
oem ported has a deeper tone than the bb.
they still sound like 361s though!


----------



## blsnelling (Jan 22, 2009)

What you're hearing is the higher RPMs of the BB. The BB saw has the factory muffler port opened with an additional hole with the Husky deflector. OEM has slots added in the front of the muffler. The cage is gutted on both.


----------



## Lakeside53 (Jan 22, 2009)

blsnelling said:


> Here's the results of the bored out carb on the BB vs the OEM ported saw. It had a 11% gain on it before. Thant's now 24% with the best times from both saws. If I average all cuts from both saws it's still a 18.5% gain. I was tweaking the tuning as I made cuts and took the fastest from each saw. The BB seems to like to run a little leaner than the OEM. Enjoy.




What did you do to the carb?


----------



## blsnelling (Jan 22, 2009)

I opened it up, probably close to 2mm. I first had to remove the brass nozzle, then replaced it after the bore was increased.


----------



## mtfallsmikey (Jan 23, 2009)

:yourock:


----------



## mtfallsmikey (Jan 23, 2009)

*Stupid Question Friday*

Brad; In your HO, would it make sense to do the BB rebuild/mods on a busted361 that could be had cheep, vs. buying a 440/441 assuming same bar length?


----------



## blsnelling (Jan 23, 2009)

There's no replacement for displacement. A ported 440's going to walk on a 361BB. Now if you're just looking for more power in a lighter weight package, then sure, build the 361. If the 361 is cheap enough, I'd jump on it. I don't think you'd be disppointed in a stock 361BB and a muffler mod. A port job will just give you that much more. If you don't like it and want a 440, you can always sell it.


----------



## parrisw (Jan 23, 2009)

blsnelling said:


> I opened it up, probably close to 2mm. I first had to remove the brass nozzle, then replaced it after the bore was increased.



Did you have to make a bigger throttle plate?


----------



## Lakeside53 (Jan 23, 2009)

I suspect he bored the venturi portion only


----------



## parrisw (Jan 23, 2009)

Lakeside53 said:


> I suspect he bored the venturi portion only



Ok, that makes sense.


----------



## blsnelling (Jan 23, 2009)

Lakeside53 said:


> I suspect he bored the venturi portion only



That is correct. I'm using the same throttle and choke plates.


----------



## yo2001 (Jan 23, 2009)

So there is no ill effect from not having a venturi?


----------



## wkpoor (Jan 23, 2009)

Brad, you are long over due for a log stand or racing stand and cants for testing!


----------



## blsnelling (Jan 23, 2009)

yo2001 said:


> So there is no ill effect from not having a venturi?



I do get a little run on at times when coming off WOT. But that's usually not an issue when cutting with it. Occasionally it will just die when you come out of a cut. One pull and it comes right back to life. So if it's your only saw and it's only for work, I don't recommend this mod. It's been recommended to try increasing the popup pressure and see if that helps. I haven't had a chance to do that yet.


----------



## treefrog359 (Jan 26, 2009)

brad have you had time to work on your 361 carb yet? did you adjust the pop off presure yet?


----------



## blsnelling (Jan 26, 2009)

Sorry, I have not. Been working on other saws the last few days.


----------



## 04ultra (Jan 26, 2009)

Brad .....slow down or the Ohio saw god will get mad that your taking all his winter time business away......


I see a race chains in your future ......  




.


----------



## blsnelling (Jan 26, 2009)

04ultra said:


> Brad .....slow down or the Ohio saw god will get mad that your taking all his winter time business away......
> 
> 
> I see a race chains in your future ......



LOL. Chains will be made before the spring GTG. How far I go with them we'll have to see.


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## 04ultra (Jan 26, 2009)

blsnelling said:


> LOL. Chains will be made before the spring GTG. How far I go with them we'll have to see.



Brad ...I have a 375 that you could get some ideas off of .........It was to fast for cutting concrete ....


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## blsnelling (Jan 26, 2009)

04ultra said:


> Brad ...I have a 375 that you could get some ideas off of .........It was to fast for cutting concrete ....



Is that the 75cc 372, or a different saw all together?


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## 04ultra (Jan 26, 2009)

blsnelling said:


> Is that the 75cc 372, or a different saw all together?





Hmmmmmmm................Its from Ohio ......


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## blsnelling (Jan 26, 2009)

04ultra said:


> Hmmmmmmm................Its from Ohio ......



Are you suggesting I race it at the Spring GTG, LOL. 


I know what you're doing. You're trying to further corrupt me on the Dark Side! It probably won't take much as much as I like this little 346.


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## 04ultra (Jan 26, 2009)

blsnelling said:


> Are you suggesting I race it at the Spring GTG, LOL.
> 
> 
> I know what you're doing. You're trying to further corrupt me on the Dark Side! It probably won't take much as much as I like this little 346.



No.......That saw along with plenty of others are in good hands ......Plus the pallet load of extra parts, bars and chains ...  



My 2153 needs to start running like its rep or its going in for work...


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## 24d (Mar 21, 2009)

Whats the bore and stroke of the 361 and the bore of the bb?


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## gonecountry (Mar 21, 2009)

24d said:


> Whats the bore and stroke of the 361 and the bore of the bb?



Bore and stroke of the 361 is 47mm bore 34mm stroke

The BB kit has a 49mm bore.


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## BigJ (Apr 27, 2009)

blsnelling said:


> Here's a shot to give you an idea how much material I removed at the flange. Notice that I did not lower the floor at all. The scribed line is from my previously modded heat shield.



Love these threads. Now I want to tear into my saws!

One question, Brad. In the pic above, you say you didnt lower the floor of the exhaust and I understand not doing so at the cylinder wall, but does it matter at the flange? I'm guessing you wouldn't gain much, if anyting, but would it hurt to do so as far out as the muffler?


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## blsnelling (Apr 27, 2009)

BigJ said:


> Love these threads. Now I want to tear into my saws!
> 
> One question, Brad. In the pic above, you say you didnt lower the floor of the exhaust and I understand not doing so at the cylinder wall, but does it matter at the flange? I'm guessing you wouldn't gain much, if anyting, but would it hurt to do so as far out as the muffler?



No reason to change the bottom of the port at all. I don't normally raise the roof, but did in this case to get the port timing numbers I wanted.


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## fishercat (Jul 9, 2009)

*taht's funny.*



Lakeside53 said:


> 150. I only speak Nikon.. it's a Stihl/Husky thing...



we don't agree on saws but we sure do on cameras.


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## Wild Knight (Jan 10, 2010)

Brad: how did the 441 BB kit work out?


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## blsnelling (Jan 11, 2010)

Wild Knight said:


> Brad: how did the 441 BB kit work out?



I never had one.


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## keith811 (Mar 14, 2010)

Austin1 said:


> Thanks for all the photography tips! although I only get about 30% of it!
> I know this went off topic but I learned allot! Thanks guy's!!!
> P.S a fancy camera costs as much as say a new 2171!!!! Got my Oxy and the garage is warming up thanks to the wood I cut.



I agree cameras are big $$$ if I had spent the munny on saws that I did on cameras I could have bought a new husky 3120 LOL


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## docrw (Feb 7, 2012)

*Yes and that's why we buy Husky's*

*Yes and that's why we buy Husky's......:msp_razz:*



Lakeside53 said:


> Like we say to Husky guys that like to beat on stihl -have you ever owed one [pro Nikon]?:greenchainsaw:


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