Camshafts, idle quality, driveability and LSA-REAL WORLD EXP and OPINION

RAMM said
Haven't used a radius VJ in years and years, sharp angles and above all round valve seats over here.

Not talking about valve jobs. Just overlap really. The discussion I would like to initiate here is LSA, not valve jobs angles or anything else to help idle quality AKA vacuum. I flow my heads in reverse all the time and almost every time they flow more up to about .250" lift backwards. I know how to help idle quality-most don't.

Don't care where the cam is installed the overlap period is the same regardless. Yes a cam can be installed way ahead to crutch idle but guess what? Now you have a stunted and F'd up power curve if everything else is correct.

I've used and observed an intake closing of about 46 deg @ .050" has nowhere near the effect on idle quality as does a wider LSA with the same intake closing.

Overlap is defined as the period of time that both the intake and exhaust valves are open. You do realize that in order for exhaust to be evident in the valve bowls of your Stage 6 example that the exhaust valve has to be open right?

The more overlap the poorer the idle. J.Rob

Then the discussion is worthless. You can't parse out bits and pieces and get the whole picture. And to say moving the ICL is a crutch is not 100% true. It has been my experience if you have to move the cam more than 4 degrees to make it work, your cam timing is wrong to begin with. The 4 degree ahead bullshit is another COMP brainwashing marketing trick. The only reason to run the cam ahead is timing chain stretch. Comp made it something else.

So if you limit the area of discussion you can never learn. Cylinder head flow has as much to do with cam timing as anything else. You are making LSA the straw man for poor reasoning.

RRR actually gets it.