Need to Identify My Exhaust Manifolds
03-11-2005, 11:46 AM
#1
Le Mans Master
Thread Starter
Need to Identify My Exhaust Manifolds
The exhaust manifolds appear to have been replaced on my '69 L46. I am considering installation of an aluminized chambered exhaust from Stainless Works.
I need to measure the exhaust manifolds to determine if they require 2" or 2.5" outlet pipes. Is it correct to assume that If I drop the pipes from the manifolds, the inner diameter of the exhaust manifold outlet should match one of these measurements?
Also, if there is a way to ident the outlet opening from the Casting number, here are the casting numbers:
RH - 3747038
LH - 3848559
Both manifolds currently do NOT accomodate AIR and therefore do not appear original to my vette.
I need to measure the exhaust manifolds to determine if they require 2" or 2.5" outlet pipes. Is it correct to assume that If I drop the pipes from the manifolds, the inner diameter of the exhaust manifold outlet should match one of these measurements?
Also, if there is a way to ident the outlet opening from the Casting number, here are the casting numbers:
RH - 3747038
LH - 3848559
Both manifolds currently do NOT accomodate AIR and therefore do not appear original to my vette.
03-11-2005, 12:25 PM
#4
Le Mans Master
Thread Starter
Originally Posted by Jeff 6T9
IIRC - the mainfolds are the same. The 2-1/2" system uses a 2" pipe from the manifold, and then joins a 2-1/2" pipe about 8" from the manifold.
03-11-2005, 12:43 PM
#5
Safety Car
2.5" manifolds were discontinued in '67, as I recall. Even the LT-1 uses a 2" manifold. The pipes for these cars starts off at 2" for about six inches and necks up to the 2.5" size.
03-11-2005, 04:11 PM
#6
Race Director
Originally Posted by gerry72
2.5" manifolds were discontinued in '67, as I recall. Even the LT-1 uses a 2" manifold. The pipes for these cars starts off at 2" for about six inches and necks up to the 2.5" size.
