Slightly strange head flow question.
Ok thanks all-
So to summarise -
If I understand correctly - if the cam can't take advantage of the peak flow of the head, there's little likelyhood of seeing any improvement, and it may go backwards due to a drop in velocity.
I also undertand the point about "averaging" the flow rate across the lift in order to determine the likely HP improvements -
BUT - is there a simple formula or theory that will give an idea of the target peak Head flow for a certain cam/combo?
I suppose I could have saved a lot of this by asking "How does a builder/head porter know when the head flows enough for the combo?"
1Wild mentioned formulas - do they apply to this issue?
In the head depot...You have to flow the head/intake/carb together and work the intake and head to flow X number with carb venturi size being used required for desired hp goal.
i cant remember right now.... but something like 11% is what a 1000cfm eats from the the total flow 'intake w/head', Ill dig into my notes..you could maybe come close by adding another 2% loss per 100 cfm decrease, maybe.
The rest is dialing the valve events per stroke/rod length and compression to max the octane being used....but basically working around the intake/exhaust system at the same time OR being very versatile with changes...
You can build around a lot of things, heads an intake...bt there so many factors....simple one like if you cant fit the size header u need in your car...
Whats this for?
Maybe some heads that flow huge in the low .1-.500 lift is what you should be after with that .540 lift cam u mention, and the rpm band is what?
Maybe the dual plane intake 'good to 7k' is the ticket 'ported of corse'...
hmmm....There was one guy who states in a video that he never had a head perform well that fell off or went turbulent like one that didnt, and he claimed even lifting the valve under the backing up, cam wise.
roll that around.