340 hp exhaust manifolds
The largest exit hole on any FACTORY small block cast iron manifold is just a hair over 2 1/4". Next one down is the 70s passenger 340 (1`7/8"). Some newer 360 manifolds are also 1 7/8". Even smaller are the 318 manifolds which are normally 1 5/8" exit hole. I've never had a 273 manifold but, if anything, they may be even smaller than the 318??? I've never seen any Mopar small block cast iron manifold larger than 2 1/4" (maybe 1/16" over that).
The only other small block cast iron manifolds that are the same size (2 1/4" plus) as the largest 340 manifolds are the ones I "machine" and sell (360 magnum passenger).
Treblig
The largest exit hole on any FACTORY small block cast iron manifold is just a hair over 2 1/4". Next one down is the 70s passenger 340 (1`7/8"). Some newer 360 manifolds are also 1 7/8". Even smaller are the 318 manifolds which are normally 1 5/8" exit hole. I've never had a 273 manifold but, if anything, they may be even smaller than the 318??? I've never seen any Mopar small block cast iron manifold larger than 2 1/4" (maybe 1/16" over that).
The only other small block cast iron manifolds that are the same size (2 1/4" plus) as the largest 340 manifolds are the ones I "machine" and sell (360 magnum passenger).
Treblig
