idle vacuum

[k-star]

Jay, is there some trick math to figure how much vacuum a engine will have with a given cam????

keith

[Jay Allen]

Jay, is there some trick math to figure how much vacuum a engine will have with a given cam????

keith
Actually no Keith. As you change intake manifold, vacuum changes. Lash changes vacuum. Lifter preload changes vacuum. Runner length changes vacuum. A long runner EFI manifold on a SBF send vacuum through the roof. Do nothing but pull the EFI off and install a Victor jr and a carb. You'll be amazed.

What I'm getting at is there are far too many varaibles just to say a cam with *X* overlap at a given compression idles like this _______ .

I have some pretty sophisticated junk that gets me close, real close. But heck you already know that!

Thanks Keith.