Any tips on 272 or 372 stock appearing porting etc.

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Better late than never

building either a 272 or 372 and need help
pls, check with 1cut, i think he can help you. The % increase in power that he says can be made will surprise you. I am a talking with experience. I had to learn how to cut again,i was cutting the trees completely off the stump too soon,or pinching in a bucking cut.pls,drop him a line.
 
Building either a 272 or 372 and need help

Take the 372 bore cylinder out to 52mm take a 272 piston which sit 1mm higher than the standard 372 piston (added compression and around 76cc)

385/390 carb, standard intake boot with impulse line tab trimmed, 372 xtorq filter mount to suit offset bolts, 372 xtorq choke horn, 385/390 carb bolts

Bolt it all together = tuff 372

I've order the parts to do these mods, I'll post back when I'm done!!
 
sounds good to me :chainsaw: , i have a 385 too so will try the carb setup for a test and have a 372 xtorq too for filter mount for a test , then replace the parts to the others when runs good then get the replacement anyhoo i,m building a BB kit on my old 372 and have a 272 BB kit too which is lucky :) so can fit that piston , but its a window piston so will that not charge so well to crankcase with the side transfers rather than the closed port 272 style ? with the piston raised by 40thou will that not be an issue with all the timing , i was thinking about machining 40thou off the crown top at say a 30deg angle or less " to create a kind of dome on it but still with correct timing , yes i do some porting , woods style or sometims a tad more on exhaust or transfers , any reply will be thankfull
 
I took the 40 thou off the squish in the cylinder because it was easier for me without a lathe, my bb cylinder needed that much to clean up and it resulted in me not having to move my transfer ports. I think Mike sells a 272 (52mm bore) or 268 (50mm) turned into a popup so you don't have to **** around doing your own machine work.
 
I use the 670 piston because it has the traditional "slipper" type skirt and windows,some 268 pistons were not. The original 272 pistons I've used are the std. windowed type too.
 
There actually 2 versions of the Tillotson HS carb,one with a small bore,and the more common one with the larger bore.Many older saws used the smaller bore HS,on these saws it's easy to swap in the larger bore HS carb body from another saw. A Homelite XL-12 for instance has the smaller bore carb,so swapping to the larger body is going to give a power gain,a bigger carb,bolt-on fit!
I'm not sure now,but I think 041 Stihls used the smaller Tillotson,so they could benefit too.

The Tillotson HS 294 and 295 carbs have the biggest bore in the HS series. They only came on Dolmar 9010 saws so are not plentiful, but they are "out there".
 
I just purchased a few Husqvarna 162se to do a build. I notice the meteor piston has more area above the ring to add ramps to the exhaust and transfer ports to change the timing. I’m thinking about working the piston skirt more too. Let’s not forget removing metal from any rotating part changes the balance too. We need to balance the complete rotating assembly.

I purchased a complete 162se bottom end(crankcase) to start the tear down for the build. Luckily I got a good crank, cylinder, case. I just need to do crankseals, crankbearings, port the cylinder and piston. I need to build a static balancer for crankshaft assemblies. There are some pics on YouTube of static two stroke balances.
 
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