Carb, Exhaust for my 300/350

[Jon S.]

I just picked up a 69 Convertible 4 spd with a 300 hp 350. I do not have the exhaust manifolds, carb or flywheel. What would be the recomended carb for good drivability? I like the 650 double pumper holly on my Pontiac. What was OE on the Corvette a Q-Jet ? My other question is are these reproduction Rams head manifolds I see all over E Bay any good? I am not so concerned with originality as functionality. As far as the flywheel i understand some 350s were internally ballanced and some externally. How do I determine this?

Jon Schurger

[William C.]

Re: Carb, Exhaust for my 300/350

350 was internally balanced, so that is not an issue. '69 Quadrajet is Part number 7029203 ofr the 4-speed version, Exahust manifolds castings 3872765, and 3932461. Have not heard of any durability problems with repro manifolds, Q-jet is afr superior to spreadbore Holley if properly set up.

[Jim T.]

Re: Carb, Exhaust for my 300/350

William Clupper in what ways is the QJet superior to a properly set up Holley spreadbore?

[Joe L.]

Re: Carb, Exhaust for my 300/350

I just picked up a 69 Convertible 4 spd with a 300 hp 350. I do not have the exhaust manifolds, carb or flywheel. What would be the recomended carb for good drivability? I like the 650 double pumper holly on my Pontiac. What was OE on the Corvette a Q-Jet ? My other question is are these reproduction Rams head manifolds I see all over E Bay any good? I am not so concerned with originality as functionality. As far as the flywheel i understand some 350s were internally ballanced and some externally. How do I determine this?

Jon Schurger

Jon-----


In addition to what Bill mentioned, the only Chevrolet 350's that were externally balanced were those equipped with a 1 piece rear seal-type crankshaft. The 1 piece rear seal crankshaft did not happen until the 1986 model year.

Most of the low cost, currently manufactured ram's horn type manifolds are made in China or India. They are configured a bit differently than originals. Also, I'm not sure that one of these is made with the forward-facing, left side alternator bracket required for 66-71 Corvettes. However, one could use the non-alternator bracket manifold in conjunction with the 72+ alternator bracket GM #14015539 or 3951337. Either of these mounts to the left side cylinder head and makes use of the bracket-style exhaust manifold unnecessary.

Just because these manifolds are made in China or India does not make them bad. Functionally, I think they'll work just fine.

[William C.]

Re: Carb, Exhaust for my 300/350

For one thing, GM engineers worked for many hours to build a fuel delivery curve matched exactly to the characteristics of the engine the carb was mated to. For another, Holley carbs are susceptible to internal leaks in the float bowl-metering block sealing surfaces that are not a problem with the Q-Jet. I think a search of the archives will give you much more information on the Q-jet vs Holley discussion, but I've seen more Holley spreadbores removed from cars than I can count.