Well im am going to be running a FP red this summer and meth injection.. Im shooting for 450-500whp...

what would be the gains from a stock cast ported n jeted mani vs a shearfab tubular mani

would i see a 20whp + gain with the shearfab?

 

This is an interesting question, I'm willing to bet the answer would depend on your boost levels. But with the red 450-500whp, I'm guessing 29+PSI. And the more HP, the more flow you'll want. I was under the impression the tubular manifolds provided this. However, I've heard the thermal properties of the cast manifolds are better. Call this post a non-answer bump for someone more knowledgeable to notice.

 

yea agree with PSI but this is what throw me off.. My buddies holds the record at buschur for a fp red or something like that.. he is making 580whp there.. he is still on stock ported mani with throws me for a loop... im sure there has been many car there with tubulars u know..

 

I asked Mike @ AWD the same thing and he told me that the ported stock manifold has a better powerband. You'd be sacrificing power somewhere with the tubular manifold.

 

basically more power up top with tubular and sacrifice low end. i prefer the tubular.