Why would low lift head flow hurt power?
What I'm kind of getting is good low flow numbers generally comes at the expense of mid-higher lift numbers ? So it's not that higher low flow numbers are bad in themselves but your generally given up better mid-higher lift numbers to get them?
This should be the case for most heads used on the street and light strip applications. The quoted words are aimed at a specific head for a specific use. He’s not wrong, but remember you can’t effectively make good usable power with a tunnel ram, twin 950’s, 2 inch tube headers, etc….
On a 7.8-1 - 318, when the rest of the package is designed toward a 400+ stroker designed to go racing in a winner take all and no prisoners.
Make a little more sense now?
Why I ask
Cause what I take from Al Noe statement is it seems they go out of their way to keep low lift flow numbers low.
There not concerned with low lift numbers because the cam is a super quick rate of lift and probably further Lu coupled with increase rocker ratios to get the valve up as quick as possible and let it hang at max lift for as long as possible. In addition, the rest of the combo is designed for all out. Of course.
In a actual bad *** race engine designed for racing, absolute max output, the thing your concerned with as far as induction is concerned, is getting as much air and fuel into the cylinder in the least restricted path as possible. This is going to happen at where ever the max cfm occurs. Yup! You bet! When the valve is wide open.
At the speed of which the event are going on, probably making lightning look slow, the valve at max lift is open a pretty long time. The biggest flow area (max lift) is also a time just before and after max lift. In this time the valve is open, the best and most amount of air and fuel are hopefully just simply pouring in.
Low lift is of nearly no concern. While it is very helpful in order to get the column air moving to help create more inertia & im sure more the merry, but the trade off of more low lift flow could come (and most likely probably does) come at an expense of not flowing as much if you don’t pay it so much attention.
This is all “RACE” 101 stuff.
The cylinder head porters, race teams, R&D teams have been struggling with a balance and still do within the as cast architecture of the cylinder head. This is why you see every so often a new cylinder head design or major modification to a cylinder head that shows just a little bit of a gain.
Let’s look at the small block Chevy head (mouse motor) in its early days and where they are now. On upper level cylinder heads, the went to moving the valves more on center while adjusting there angle sometimes and using a Chrysler like rocker arm system.
Glad your asking about this.