Any Interest In Revisiting Porting The 550XP?
- Thread starter Mastermind
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For $10 you can have a pair of 550XP crank stuffers.
You're all a bunch of weirdos.
Seriously.
Seriously.
Mastermind
Work Saw Specialist
Mastermind
Work Saw Specialist
Us? Have you ever read any of your posts?
Think he gotcha Chuckar ! :hmm3grin2orange:
Terry Syd
Addicted to ArboristSite
Since the transfer covers on the 545 restrict the transfer flow a bit, then dropping the jug and removing some time/area on the transfer ports won't make as much difference. In other words, the 545 is a better candidate for this mod as it is a less expensive saw.
When you add $10 for the crank stuffers, you will probably have the equivalent power of the modded 550.
OK, here's an idea - port the strato cutaway on the piston to increase the timing to the intake timing. That should increase the flow up on top end and you may not need the stuffers. Without the stuffers peak torque will be a bit lower in the powerband.
When you add $10 for the crank stuffers, you will probably have the equivalent power of the modded 550.
OK, here's an idea - port the strato cutaway on the piston to increase the timing to the intake timing. That should increase the flow up on top end and you may not need the stuffers. Without the stuffers peak torque will be a bit lower in the powerband.
Us? Have you ever read any of your posts?
Fortunately no. If I knew half the crap I spit out on this site it'd make me dummer than the rest of those who read such garbage.
But thanks for asking.
:msp_angry: GAFL.
Mastermind
Work Saw Specialist
Thanks for these posts Terry, it makes the wheels in my head start turning.....
I love you Mang. :msp_biggrin:
Terry Syd
Addicted to ArboristSite
Randy, I've never run a 545/550 let alone run one of your modded ones. I don't know what the 'feel' of the saw is, all I can offer is some tuning concepts that you may be able to play with.
We don't have saw dynos to work with, so we are left with cutting up wood. Along those lines, I've started using an 8 pin to load the saw some more so I can get a better feel of the powerband. Since the saw is slowed down a bit, I can pick up a bit more of the subtle changes.
The crank stuffers is something you may be able to offer to your customers as an option. If someone is using the 445/550 for an all around saw, they may want the broader powerband afforded by the just the crank. However, is someone wants a high revving saw, albeit with a shorter powerband, so they can they can do their limbing, then the stuffers can be offered.
It's the old story of 'horses for courses'. Different jobs, different tools - the crank stuffers can allow you to offer that option.
EDIT: I should mention that my experience with matching the strato and intake timing is related to a special case - my saw. I've got a bigger carb and with the strato intake, the combined area is the equivalent of a 19mm carb (on 50cc).
I've also got a 13,000 limiter which prevents me from playing any further. I'm already on the limiter and have to load the saw in smaller wood to keep it from misfiring. If I had a higher limiter, I would have sacrificed a piston to the 'God of Speed' and kept increasing the strato timing.
The consensus of the tuners is that about 160 duration is about as far as you want to go to keep a reasonable idle. However, after the saw is in the wood, a longer duration could give you more power. OK, the Husky strato is two ports, the second one for the strato doesn't come in until about half throttle - that gives us another tuning option.
My thinking is that an intake timing of 160 puts you in a safe zone, and then keep trimming the piston on the strato timing until you've gone too far. Maybe there is some extra power by taking the strato timing out to 170-175 - you don't know until you've been there.
EDIT: If you did try the extra strato timing and it didn't seem to help, you may have created another problem - extra cylinder charging, which needs more blowdown. With the sacrificial piston all you need to do to test it is to add a few degrees (two should be enough) by nipping about 1/2mm off the front of the piston.
We don't have saw dynos to work with, so we are left with cutting up wood. Along those lines, I've started using an 8 pin to load the saw some more so I can get a better feel of the powerband. Since the saw is slowed down a bit, I can pick up a bit more of the subtle changes.
The crank stuffers is something you may be able to offer to your customers as an option. If someone is using the 445/550 for an all around saw, they may want the broader powerband afforded by the just the crank. However, is someone wants a high revving saw, albeit with a shorter powerband, so they can they can do their limbing, then the stuffers can be offered.
It's the old story of 'horses for courses'. Different jobs, different tools - the crank stuffers can allow you to offer that option.
EDIT: I should mention that my experience with matching the strato and intake timing is related to a special case - my saw. I've got a bigger carb and with the strato intake, the combined area is the equivalent of a 19mm carb (on 50cc).
I've also got a 13,000 limiter which prevents me from playing any further. I'm already on the limiter and have to load the saw in smaller wood to keep it from misfiring. If I had a higher limiter, I would have sacrificed a piston to the 'God of Speed' and kept increasing the strato timing.
The consensus of the tuners is that about 160 duration is about as far as you want to go to keep a reasonable idle. However, after the saw is in the wood, a longer duration could give you more power. OK, the Husky strato is two ports, the second one for the strato doesn't come in until about half throttle - that gives us another tuning option.
My thinking is that an intake timing of 160 puts you in a safe zone, and then keep trimming the piston on the strato timing until you've gone too far. Maybe there is some extra power by taking the strato timing out to 170-175 - you don't know until you've been there.
EDIT: If you did try the extra strato timing and it didn't seem to help, you may have created another problem - extra cylinder charging, which needs more blowdown. With the sacrificial piston all you need to do to test it is to add a few degrees (two should be enough) by nipping about 1/2mm off the front of the piston.
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Randy
After some days of rain today was to try my 550 G . She starts after two pulls and trottle as she should do.
First i was cutting some 10-12" douglas fir with 16" bar and 3/8-7 RSC..goes through like butter
Then changed to 325-7 for some oak cuts in same dia. and she still holds the rpms ,unbelievable .
I'm pretty sure she will do with 3/8 in oak or 325-8 in soft wood as well after 20 tanks or so .
Thank you Mastermind for that killer saw ,mayb i see a MM 562 G laying under my christmas tree ...:msp_wink:
Thore
After some days of rain today was to try my 550 G . She starts after two pulls and trottle as she should do.
First i was cutting some 10-12" douglas fir with 16" bar and 3/8-7 RSC..goes through like butter
Then changed to 325-7 for some oak cuts in same dia. and she still holds the rpms ,unbelievable .
I'm pretty sure she will do with 3/8 in oak or 325-8 in soft wood as well after 20 tanks or so .
Thank you Mastermind for that killer saw ,mayb i see a MM 562 G laying under my christmas tree ...:msp_wink:
Thore
Mastermind
Work Saw Specialist
Thanks for the feedback Thore.
We ain't going anywhere my friend.......whenever you are ready for another saw, just let me know.
3/8 and dont worry about the wood for me
Randy's definition of a work saw takes a lot of the "need to figure out what to do" out of the equation.
My 346 xp he just did for me has about 5 tanks of fuel through it in the last 2 weeks. It has a 16" 3/8 - 7 on it and it builds mounds of chips burried in red oak. I love the saw. Terry's 2253 shows up tomorrow. To me its not which is better. Better has a lot to do with the operator. I cant tune like some of you can on here. Randy knows this and tunes to where the saw is safe from my tuning ability. The 2253 takes my limitation out of the game. However I have come to understand that if any of my ported 50cc saws wont easily slice through oak with a 3/8 sharp chain, then I need to return the saw for one of them to look at it.
I MM and tuned my Echi 271 and it cut ok. Terry retuned it at his GTG. I had it way too rich, trying to protect the saw. Terry then really opened my eyes on this area. He said " Tuned rich is not bad, but its a lot better to be tuned right." Now my little 27 cc Echo has a 12" .325 on it and it will easily cut 12" oak.
A ported 50 cc saw should easily handle 3/8 in oak. :msp_thumbup:
Randy's definition of a work saw takes a lot of the "need to figure out what to do" out of the equation.
My 346 xp he just did for me has about 5 tanks of fuel through it in the last 2 weeks. It has a 16" 3/8 - 7 on it and it builds mounds of chips burried in red oak. I love the saw. Terry's 2253 shows up tomorrow. To me its not which is better. Better has a lot to do with the operator. I cant tune like some of you can on here. Randy knows this and tunes to where the saw is safe from my tuning ability. The 2253 takes my limitation out of the game. However I have come to understand that if any of my ported 50cc saws wont easily slice through oak with a 3/8 sharp chain, then I need to return the saw for one of them to look at it.
I MM and tuned my Echi 271 and it cut ok. Terry retuned it at his GTG. I had it way too rich, trying to protect the saw. Terry then really opened my eyes on this area. He said " Tuned rich is not bad, but its a lot better to be tuned right." Now my little 27 cc Echo has a 12" .325 on it and it will easily cut 12" oak.
A ported 50 cc saw should easily handle 3/8 in oak. :msp_thumbup:
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Mastermind
Work Saw Specialist
For only 3 easy payments, they can be yours!!!!
opcorn:Big box going out in the mail today for you sir. One box, buncha stuff. Things haven't gone as planned here in the last couple of days, kind of a whirlwind week. Would you like the stuffers sent with?
Those aren't for controlling your moobs, Randy.
Mastermind
Work Saw Specialist
For only 3 easy payments, they can be yours!!!!
Big box going out in the mail today for you sir. One box, buncha stuff. Things haven't gone as planned here in the last couple of days, kind of a whirlwind week. Would you like the stuffers sent with?
Yes Sir......I wanna stuff a 545.....but I need a case gasket too.
No controlling these bad boys Wes......
http://malebreastremoval.com/wp-content/uploads/2013/05/get-rid-of-man-****s.jpg
YOu were angry back when you were 12!
