Compression/Blowdown Question

[thompsoncustom]

when porting and modifying a saw how does compression effect where u set your blowdown at?

Does a saw with 190psi require more or less blowdown than a saw at 150psi?

 

[NSEric]

I dont think so.
But im waiting for more replies so I can learn more about porting.

I find the height of the exhaust port has a big effect on blow down.
IE a 50 cc saw with the exhaust at 105 needs the transfers at close to 120 for about 15 degrees of blow down but a bigger saw with the exhaust at 100 still needs the transfers at about 120 but that gives 20 degrees of blow down.