Which to mod, 046 BB or 066

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The 066 BB (prototype) stock is behind a stock 066 jug, though it does have great low end.

Once modified they are pretty close in cut times, however it is not easy to take the 066bb to the same level of modification as an older 066 Stihl jug (not the new 660 as it is different). Squish on the bb comes out pretty close ~.020 to .025 with the gasket in.

The gains from stock to modifed that can be made are greater with the BB mostly because the BB start out a little lower. The main performance issue I noted with the BB was very short transfer duration.

The 066 BB does turn lower RPM than the Stihl jug both stock and modded with simmilar port numbers. But does make up for that with some torque.

There may be changes to the BB before it becomes final production, so who knows?

That is what I am hearing that is why it is being delayed in being made available to the general public just yet was supposed to be in late Jan now late Feb is what I was told due to changes.............
 
an 066 jug

i suppose that it wouldn't hurt to find a used 066 jug and mod it accordingling and try it on the saw, and see what happens, that way id still have the original jug to come back to if anything went wrong, i also do have the original 046 cylinder that i could mod, but not sure that i want to yet, thanks for the help, alot good info coming out of this thread

btw-what sort of torque specs does a 66 cyliner call for?
 
Stock BB vs stock OEM for milling

Hi all:

Would a Stock BB have any advantage over a stock OEM cylinder for milling applications on an 066? I'm thinking the BB should have more low-end torque, which should be an advantage for milling.

Cheers,

Don
 
046 BB kit ?

I just read this on another forum. any truth to the poor combustion chamber on the 046 BB kits?



From another fourm= Posted: Tue Jan 16, 2007 1:26 am Post subject: Bailey's 046 Big Bore Kits

I only used two of them and I consider it two to many. After looking at the first one it wasn't hard to see that it had a huge combustion chamber, way larger then the factory one. The chrome looked usable as well as the piston. The cylinder does have some small ports but there is enough metal to correct that problem.
After bolting the cylinder on the saw it was obvious that I had a problem. The piston didn't have enough room to clear the case and it would lock up solid. I hade to remove the crank, bolt the case together, set it up in my mill and machine out the case for clearance. So now I have new gaskets, seal kit and bearings in a saw that just needed a top end. I am not sure it is worth the trouble. I ran it stock first and I think that it is slower then a stock cylinder with a standard bore. Ported it does run a lot better but I am not sure if a standard bore ported 046 is any slower.
I tried number two BB 046 kit and I had to mill out the case on that one also.
I just hope that the kits for the 372's they have coming are better then the 046 BB kits.
END
Just wonder if this was suppose to be for the 066 BB kits and they typed 046 BB instead. I did ask to see which one they meant. Will update.
 
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The early 046BB had a ring that was about 1/16" thick that was on the outside of the squish. This was brought to Bailey's attentiona nd they fixed the problem. They worked, but eh newer ones are way better.

Now as to which saw to modify, I would ask you which is more important; weight or brute power? You can make the 046BB out run a 066 and save a lot of weight; however if you need the power of an 088 then I would go with the 066.
 
066 vs. BB046

i plan to ultimately mod both of them(most likely) im more of the type that likes brute power, im leaning towards having some one else do it, what sort of power do u get out of these at WHS, ballpark horsepower? thanks again
 
I can attest for the 460BB numbersDean has. My saw has some extras with it, but it will outcut a stock 066/660 anyday in any size wood!
 
I can attest for the 460BB numbersDean has. My saw has some extras with it, but it will outcut a stock 066/660 anyday in any size wood!

Does it outcut a 660 with a dual port muffler in a 30 inch wood? Pity you're so far away or we'd have to try it in my back yard! Maybe throw it on the mill also...
 
extra's??

what are these extra's that u speak of??? i believe when i get it done i will have something like a stage IIIT performed. pros & cons of this decision?
 
Andy...like I said a STOCK 066/660

I had a stage 3T done to mine and had Dean do a few extras to it as well. I am a greedy bastard when it comes to power, although I like my relaibility too.

Ill leave posting all the work that was done to my saw to Dean if he wishes. Not trying to dodge the question or back anyone into a corner just fel its no my place to say.
 
more power!!!!

im the same way, i look at it as the more power the better, but i gotta have a saw that is reliable-if it isn't there will be a chainsaw toss in the woods!!!! i'd like to mod it to get the most power possible without loosing reliability or longevity-or is this a double standard?
 
Andy...like I said a STOCK 066/660

I had a stage 3T done to mine and had Dean do a few extras to it as well. I am a greedy bastard when it comes to power, although I like my relaibility too.

Ill leave posting all the work that was done to my saw to Dean if he wishes. Not trying to dodge the question or back anyone into a corner just fel its no my place to say.

I know you said stock :) ... but a DP is awfully quick to slap on / re-tune . I'm so happy with my 066 (660 model) I'll not "mod" it further.
 
Does it outcut a 660 with a dual port muffler in a 30 inch wood? Pity you're so far away or we'd have to try it in my back yard! Maybe throw it on the mill also...

Andy, I am in your back yard and you are welcome to visit any time you want. Let me know when you are thinking about coming down and I will buy lunch and a beer and we can cut some wood. I always have saws that are built or in the middle of.

The extra's that Jim is talking about is a Spansky style cut. Jim's was cut .035 off of the base and out of the crown. Also the transfers had some extra work done to them.

The big deal is not in the fact that the saw will out do a muffler modified 660 but the fact that it will out cut a stock 660 and weighs 2.5 pounds less!
 
On the milling though, milling is hell on saws.

I niksil is a good bit more durable than chrome, and does a better job keeping lubrication, small nicks and scratches don't thed to spread in niksil like the do on chrome.

Just an opinion, but I think the hard service of milling would do in a chrome plated aftermarket jug before a Stihl jug, but would it wear 3 time faster to offset the lower cost? Don't know.

As far as lowend torque, there might be some advantage there.
 
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hey dean!!!

hopefully i am going about this the right way, kinda new on here, but what would u charge to mod an 066 or an 046BB and get the most possible power and still be reliable, including any "extras" to boost power, thanks millions to you guys.
 
The other key to this conversation is that the 460BB is on a 440! I love this saw!

Does it have a funnel type muffler?
If so I may have ran it up there. Dean had a 440 up there that still had the 440 BB kit, but was getting ready to put a 460 bb on it. I ran it with the 440 kit and I kicked some serious ARSH!
 
Not sure what a funnel type muffler is. The saw was barnd new not even one tank through it when Dean recieved it.
 

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