68 exhaust manifolds

[Steve Z.]

what are the opening size for the original ram horn style exhaust manifolds?are they larger than other chevys? how can you tell if a luggage rack is original or added later? thanks,steve

[Joe L.]

Re: 68 exhaust manifolds

what are the opening size for the original ram horn style exhaust manifolds?are they larger than other chevys? how can you tell if a luggage rack is original or added later? thanks,steve

Steve----

ALL Corvette "ram's horn" exhaust manifolds used for 1966 and later were 2" outlet. The 2-1/2" outlet manifolds were used only for some Corvette small blocks in the 1962-65 period; none thereafter.

All 63-75 Corvette luggage racks were either dealer installed or customer installed. None were installed at St. Louis. As far as "originality" is concerned, it does not matter if the rack was dealer installed prior to delivery of the car or installed later by a dealer or customer. They are all considered to be non-original.

[Steve Z.]

Re: 68 exhaust manifolds

thanks for the reply--- i guess the larger the size opening the more air could be forced thru it thus more hp. probably not too many of the larger opening ones left anymore? if you had a 300 hp or larger motor would you need the larger ones or could you still use the smaller ones?

[Joe L.]

Re: 68 exhaust manifolds

thanks for the reply--- i guess the larger the size opening the more air could be forced thru it thus more hp. probably not too many of the larger opening ones left anymore? if you had a 300 hp or larger motor would you need the larger ones or could you still use the smaller ones?

Steve----


1970 Corvettes were built with 350 hp and 370 hp small blocks. Every single one had 2" outlet manifolds.

The 2-1/2" outlet manifolds are easily available in reproduction. However, NO 2-1/2" outlet manifold was ever made that was equipped with AIR fittings. ALL 1968 Corvettes were equipped with AIR. So, there's no way to install 2-1/2" outlet manifolds on a 1968 small block and maintain the AIR system.