What do I have here?

[wiscane]

I have a 1965 roadster 327 - 300hp. Would the stock exhaust manifolds be 2" or 2 1/2" ?? I read somewhere else on this newgroup that a member had a 1967 327- 350hp motor with stock 2" exhaust header. I can't imagine that a larger horsepower motor would have smaller exhaust headers !! However, looking through a restoration book led me to that conclusion. I must have misread this info Thanks.. Ed:confused

 

[Ron Miller]

Stock for the '65 327 300hp are 2 1/2" mainfolds. Starting in 1966 the 327's all used 2" exhaust manifolds, the higher hp engines used 2 1/2" exhaust systems, but the pipes necked down at the exhaust manifold to 2".

May sound odd, but there's really not a lot of difference in restriction between the two different 2 1/2" exhaust systems.

rlm:cool

 

[61 Silver]

65 exhaust

Hi! Ed

The exhaust manifolds for a 1965 with the base 250HP engine and the 300HP engine with Powerglide have a part number of: 3846559 left and 3750566 right and have a 2" exhaust system.

The 300HP, 300HP with Powerglide w/ air (not sure of exhaust system size for power glide but believe it should be a 2 1/2" size), 350HP, and 365HP manual transmission, used 3846563 left and 3797902 right with 2 1/2 " exhaust.

There is also different manifold usage when air condition option or higher HP engines are used.

Very confusing, but if you purchase a 1965 Corvette Technical, Information Manual and Judging Guide from the NCRS book store it has a chart that provides the information you requested.

 

[wiscane]

Thanks Ron and Ray... It is confusing! I had an opportunity to pick up a slightly used 2" chambered exhaust off a 1967 327 300 hp. I thought they would be the same size. Oh well... I guess instead of working on my car ... I'll just go outside and cut the grass and wash the car :cool ... thanks ... Ed

 

[61 Silver]

Ed

Could be worse, you could come and shovel the snow in my driveway!
Ray