Quote:
Originally Posted by Logic
Don't you mean smaller DURATION cams, so that there is less valve overlap between the exhaust and intake stroke?
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If you read the specs published with the cam, the duration automatically changes with the lift, kind of the point. Overlap can sometimes remain the same based on the start point of the opening when you grind the blank. Overlap calculations are above my paygrade. The top fuel people have massive cams, but they do not idle at 800 rpm because the flows, having mass, interfere with each other at low speed and you huff raw mixture sometimes burning, out the exhaust, which is rather exciting. See "zoomies" at night drags. More exciting is huffing hot exhaust out the intake which is why the roots blower is chained to the vehicle. Turbos just generally grenade the engine compartment. Prolly wouldn't notice that in an econo box.
The real trick with cams is calculating the effects of the changes and whether or not they improve your situation. Everyone I knew guessed and hoped. Luckily you can swap a cam between races if you can tolerate leaks & a wee loss in efficiency