i have a 71 chevelle. i bought a 454 from a 73 police package. will the nodular iron manifolds fit? if so how do they breath?

They will fit and breath as well as any stock manifold.

The Clarys, on the Yenko web site, have their "Certified Stock" COPO 427 Camaro running low 12s the last time I checked. The manifolds don't seem to be holding them back. Makes you wonder if headers, for a street application, are worth the hassle.

The Clarys, on the Yenko web site, have their "Certified Stock" COPO 427 Camaro running low 12s the last time I checked. The manifolds don't seem to be holding them back. Makes you wonder if headers, for a street application, are worth the hassle.

for the street I never thought headers were worth all the burnt wires,low ground clearance & oil filter,spark plug fit issues.:noway:

I picked up 4-5 MPH and 2-3 tenths when I swapped out my manifolds for headers,no other changes..I even reused the same pipes and mufflers.
My oil filter clearance is just fine,ground clearance is just fine (they are not Hookers) and I have never burnt a plug wire :)

I picked up 4-5 MPH and 2-3 tenths when I swapped out my manifolds for headers,no other changes..I even reused the same pipes and mufflers.
My oil filter clearance is just fine,ground clearance is just fine (they are not Hookers) and I have never burnt a plug wire :)

your the exception;):p

your the exception;):p

No,not really :)
I have Oldsmobile manifold to header swaps testing that gained too!

I picked up 4-5 MPH and 2-3 tenths when I swapped out my manifolds for headers,no other changes..I even reused the same pipes and mufflers.
My oil filter clearance is just fine,ground clearance is just fine (they are not Hookers) and I have never burnt a plug wire :)

same here with me that's 2 exeptions

for the street I never thought headers were worth all the burnt wires,low ground clearance & oil filter,spark plug fit issues.:noway:You can add me to that list.I put headers on my 66 in 1972.I never had a ground clearance issue,used the canaster(sp)filter for years and never once burned a plug wire.

When I was trying to get mine in I had to act like a gymnast, only to find the pipes were too big. One side fit fit fine, the other was another story! I hit it hard for about 10 minutes and the other finally went in. I will never have a pair of Hookers in my garage again!

Hedmans from here on out!

ive burned one plug wire with headers and that is because i didnt use seperators and the wires were sloppy. no other problems.