V8RX7FTW

iTrader: (6)

I need to make a set of manifolds and am planning on using either schedule 5 or 10 tube to make up the manifolds. 1 1/2 will give you over 1 3/4 inner diameter and the 10 will be slightly undersized. Let me know what is better and what your running. Also what size should the crossover pipe be 2.5 or 3 inch. Turbo is a borgwarner s475 and I am shooting for north of 800hp.

MeanYellowZ

iTrader: (19)

I just used the 2" stuff on a 402 Im finishing up. Fun stuff to work with....not. I think for 370 or under cubes the 1.5 stuff would probably be okay, but 800 hp might start to push the limits.

V8RX7FTW

iTrader: (6)

i may do a 402 or a 408 in the near future Space is the biggest issue not sure if the 2 inch will fit as its a little bigger than 2 inches

Shearer

2" pipe is way too large.

V8RX7FTW

iTrader: (6)

so the 1.5 should work ok then? Scd 5 or 10?

pwrtrip75

iTrader: (8)

Yes, 1.5" is plenty big, I use that size schedule 10, sch 5 would be to thin I would think, heat cycling = crack.. the inside of the pipe is bigger than the exhaust port just slightly.

The header flanges are lasered from the exact same size as the factory gasket. This header is the 1.5" sch 10

MeanYellowZ

iTrader: (19)

I built my these logs out of 2" schedule 10 since the cubes were big and since it was a log I dont think the bigger size hurts it. I hope the bigger area inside helps overcome the hindrance of the log itself.