switching to 801 intake -need carb help

[Dale P.]

I am making a change on my 68 427/400 from the 3x2 set up to an 801 intake and Qjet (or??) .. the 801 should should be a easy swap but now comes the question of what carb to run and how to set it up. So I am looking for suggestions to help get me started. the car is a 4 sp with 3:70 gears. it is in fact a true 400HP car and I am just tired of trying to have everything perfect .. I am at the age I just want to drive the wheels off of it. been asked why the 801 ,, well two reasons ,, it was the only one that I know of that will fit under the hood and I had it.

[Joe L.]

Re: switching to 801 intake -need carb help

I am making a change on my 68 427/400 from the 3x2 set up to an 801 intake and Qjet (or??) .. the 801 should should be a easy swap but now comes the question of what carb to run and how to set it up. So I am looking for suggestions to help get me started. the car is a 4 sp with 3:70 gears. it is in fact a true 400HP car and I am just tired of trying to have everything perfect .. I am at the age I just want to drive the wheels off of it. been asked why the 801 ,, well two reasons ,, it was the only one that I know of that will fit under the hood and I had it.

Dale-----


I think you're making a smart move for driveability and enjoyment of the car. The '801' is a very good choice for a manifold, too. The 68-69 L-36 aluminum manifolds as well as the 70-74 LS-5 and LS-4 cast iron manifolds are the only DUAL PLANE, large oval port, Q-Jet manifolds that will fit under a 68-74 Corvette hood. The only aftermarket manifold that's large oval port and will fit is the Edelbrock Torker II, but it's a single plane manifold and I do not recommend it for street use.

As far as a carb goes, I'd use any of the 68-69 Q-Jet small block carbs, "rejetted" (jets and metering rods) for a big block. While unfortunately no longer available new, these carbs are plentiful in used form.

[Dale P.]

Re: switching to 801 intake -need carb help

Joe,

thanks for your great advice as always you are a wealth of knowledge. I will begin my search for "the Qjet" ,, any recommendations on a reliable carb rebuilder who will know what I need when I take my carb to them? I had heard something about differnet jets from side to side ?? confused on that one

[Clem Z.]

Re: switching to 801 intake -need carb help

i have bought parts from this company and have been well satisfied. http://www.carburetion.com/quadrajet.asp

[Clem Z.]

Re: switching to 801 intake -need carb help

i have bought parts from this company and have been well satisfied. http://www.carburetion.com/quadrajet.asp

http://www.carburetion.com/_inv/carb...s.asp?CU=4-209. 1968 BBC carbs are the following 7028210,211,216,209,218,217 and they list some on their website. 1969 BBC carbs are the following 7029200,201,204,215. they should also work

[Tom P.]

Re: switching to 801 intake -need carb help

Dale-----


I think you're making a smart move for driveability and enjoyment of the car. The '801' is a very good choice for a manifold, too. The 68-69 L-36 aluminum manifolds as well as the 70-74 LS-5 and LS-4 cast iron manifolds are the only DUAL PLANE, large oval port, Q-Jet manifolds that will fit under a 68-74 Corvette hood. The only aftermarket manifold that's large oval port and will fit is the Edelbrock Torker II, but it's a single plane manifold and I do not recommend it for street use.

Additionally, any of the pass car (full size car, Chevelle, etc), BB396-402-427-454, cast iron manifolds with the Q-jet bolt pattern (they're all oval port design), from 68-72, should work just fine, and those manifolds should be VERY plentiful at any swap meet. The prices should range from FREE to about $25. This style of iron/Q-jet manifold is VERY undesireable, thus, dirt cheap, because it has almost zero performance value. From my viewpoint, the 73-later manifolds are even less desireable (translate junk) for your application because they will have provision for the EGR valve.
As far as I know, the ONLY alum/Q-jet BB manifolds were used on 68-69 Vettes. Such an animal was never used on any other Chevy product (Nova, Chevelle, etc) which makes this style manifold somewhat scarce and they tend to be somewhat pricy.

[Joe L.]

Re: switching to 801 intake -need carb help

Additionally, any of the pass car (full size car, Chevelle, etc), BB396-402-427-454, cast iron manifolds with the Q-jet bolt pattern (they're all oval port design), from 68-72, should work just fine, and those manifolds should be VERY plentiful at any swap meet. The prices should range from FREE to about $25. This style of iron/Q-jet manifold is VERY undesireable, thus, dirt cheap, because it has almost zero performance value. From my viewpoint, the 73-later manifolds are even less desireable (translate junk) for your application because they will have provision for the EGR valve.
As far as I know, the ONLY alum/Q-jet BB manifolds were used on 68-69 Vettes. Such an animal was never used on any other Chevy product (Nova, Chevelle, etc) which makes this style manifold somewhat scarce and they tend to be somewhat pricy.

Tom-----

Yes, the only use of aluminum, spread bore flange, big block manifolds was 68-69 Corvettes. There were 3 different castings over the period but they vary in only extremely minor ways. In fact, the casting numbers are the biggest difference between them.

As far as similar cast iron manifolds go, the 70-74 Corvette manifolds were the same ones used on most other Chevrolet big block applications over that period. Such low profile manifolds were not actually required for the other Chevrolet car applications but I suppose that Chevrolet just decided that they would standardize on a "one-configuration-fits-all". The same thing was true for 1970-71 LS-6/L-78 aluminum manifolds; the low profile was not really required for other-than-Corvette models, but only one manifold design was used for all.

There were 2 other cast iron, oval port, spread-bore flange, big block manifolds used over the 66-69 period. These were castings GM #3889348 and 3931067. However, I don't think that either of these will fit under the 68-72 Corvette big block hood. They MAY fit under a 73-74 Corvette hood.