Port Heights change due to Squish band change????

[rolloman]

Racing only. It is my first saw to build. I want to do as much as I can to it with the exception of a two piece cyl/head.

 

[troutfisher]

That opens up a few options, especially with the carb and fuel.

 

[rolloman]

No problem SpaayDawg were all allowed one mistake. Haahaa.

No epa junk here. Muffler completely gutted. Has triangular tube same dimension as the port that goes from flange all the way thru to the mufflers outside front.

Transfers:

Open: 121*
Duration: 118*

I meant rectangular tube

 

[Meadow Beaver]

If you were to mill .035" off the base of the cylinder and then mill .035" off the combustion chamber you would have to raise the exhaust .035" to get stock timing back. Otherwise, if you didn't equal that out, it would retard the exhaust timing, but have gobbs of torque.

 

[troutfisher]

How about extra transfer ports, like internal finger ports or external boost ports?

 

[Meadow Beaver]

Finger ports are over rated....unless you have the right saw.

 

[troutfisher]

Finger ports are over rated....unless you have the right saw.

I agree, external boost ports are the way to go. Finger ports are easier to do, and there are some gains to had.....and just fun to try for someone new to porting saws.

 

[Meadow Beaver]

I've found that with most newer stihls it is pointless to use finger ports. Just widening the stock ports will have better results.