On an EFI application when runner size is known and so forth?

 

If only it were that simple.

To design an intake that is anywhere near "optimum" would require a bit more information than given here. There is no rule of thumb plenum volume that works for every situation. Variables of much greater importance would include runner taper angle, runner length, length to taper break, etc..

Take care

 

wow chuck your alive....Where should i start looking or what would be the basics that i would need..I plan on dyno testing the engine with a carb and a used sheet metal box upper later this month.. The car the engine is gioing in needs a lot lower intake to fit..Or am i just gonna have to build what fits and deal with it?

 

What kind of engine are we talking here?

If it is a Ford or symmetrical port chevy (ala brodix BD2000, LS6, etc) then it will be a piece of cake because you can get lots of runner length with a dual plenum setup and still fit everything under the hood.
If not, then you have to build what you can fit under the hood. The real question is, how much runner length is required? If this is a drag race engine then the answer is most likely, "not much". But then we have to take into account the transmission, converter, weight, gearing, intake port cross-section area and a lot of other pertinent variables. Nothing simple about it.

Give me some information and I'll throw some other ideas at you. No such thing as too much info here, otherwise we're shooting in the dark.

Take care