Would enlarging the seconaries on a GSR manifold by a machine shop produce more power? or even enlarging my throttle body?

Thanks!

 

Here's an idea, it would only be for turbo or wild all motor cars. Why not take the secondary portion and the top half of the manifold and cut it all out. The runners will be short with a large feed to a huge plenum. Good for high end only.

 

Just get the Skunk2 one.

 

this is what erick's racing did to their car....

 

Just get the skunk2 one. Dont deal with the hassle.

 

Not a bad idea, but there are some complex issues involved in calculating proper plenum & runner size. I read an interesting article awhile back, I believe it was written by Michael Delaney, regarding the effect of runner and plenum size and their effect on cylinder filling. The jist of it was that the size of the two need to be carefully controlled to promote proper timing of pressure waves with the intake valves.

 

You are correct, we recently dyno'd a Sentra Spec-V with a home grown sheetmetal intake manifold. Power was about 10HP less than any other stock Spec-V we have seen.


[Modified by lightning, 5:29 PM 10/5/2002]

 

Chances are the pressure waves going through the intake runners and plenum are returning just in time to meet a closed intake valve.