Leakdown test on Cheetah PV

[Wildcardracing]

The 230's are a good starting point. If it has a high rpm bog then comes alive again, go up on them. This is a sign the PV's are opening too late. Remember, as you make changes to the pv you will also have to look at jetting again. If it feels like it's lacking on bottom to mid, the PV's could be opening too soon. Best time to consider some dyno time, these aren't as simple to tune as a cub or stock cyl motor.

 

-Brandon

[hercalmighty]

Thanks. I appreciate the help.

Do you have a good starting point for jetting?

472 cheetah

Cpi small bores

93 octane mixed to 40:1

39 pwks with 8" k&n

Sea level

75 degrees

About 150 psi

+6 timing

[trickedcarbine]

Damn.... Brandon just let a great nugget of knowledge out right there. Not many threads with exhaust jet sizing if any.

[hercalmighty]

Yep. Glad someone is willing to put it out there.

 

So, does anyone have some insight on my jetting?

Im thinking about starting with 48 pilot, cel middle clip, 165 main, 1.5 turns out on air screw.