I've ported a husky 440 and a couple of old macs which are clamhells. The macs wake up the best but I've gotten good results from all of them. I usually widen the exhaust 60-70% of bore so you get those gasses out fast but maintain compression. Trying to find or modify the carbs also helps. These saws are so choked down getting air in and to flow better helps them so much! Also advancing ignition timing wakes almost any saw up and doing piston work helps quite a bit. Lightening the piston helps with throttle response from what I've found.
I am Working on strato poulans , going to pick up a ms 170 to mess with as well , but Have you tried blocking off the strato port and lowering the bottom of the intake and taking a couple of thousandths off the piston skirt ?
I’d be careful on how far you lower the intake. I have shaved off the piston, but have not tried blocking any of the ports. I’m not big on the Strato style engines and have only ported a few. I try my best to get my hands on the older gens. Good lucky!
Excellent info 👌 I personally knew... You are a straight shooter. Nice to have you in the saw building community 👍
I've ported a husky 440 and a couple of old macs which are clamhells. The macs wake up the best but I've gotten good results from all of them. I usually widen the exhaust 60-70% of bore so you get those gasses out fast but maintain compression. Trying to find or modify the carbs also helps. These saws are so choked down getting air in and to flow better helps them so much!
Also advancing ignition timing wakes almost any saw up and doing piston work helps quite a bit. Lightening the piston helps with throttle response from what I've found.
Great info… thanks for watching!
I am Working on strato poulans , going to pick up a ms 170 to mess with as well , but Have you tried blocking off the strato port and lowering the bottom of the intake and taking a couple of thousandths off the piston skirt ?
I’d be careful on how far you lower the intake. I have shaved off the piston, but have not tried blocking any of the ports. I’m not big on the Strato style engines and have only ported a few. I try my best to get my hands on the older gens. Good lucky!
I did mine also😊it runs better