frankenstein q-jet wont idle

[GASGTO73]

I have been a pontiac man for 30+ years, and rebuilt too many O-jets over the years  ; )

What i am trying to do is build a 1972 800 cfm buick center with a 73 pontiac base plate and top.

Jim Hand built one and mentioned it over on Wallace racings website. so I built one myself.

buick carb # is 7044241 KJ. the top and base plate are from carb # 7043264 JC (73 gto).


I cant get this hybird / frankenstein to idle at all. It will rev ok, good throttle response, but no idle.

It acts like the idle circuit is not even there. FYI, my other carb runs flawlessly on the  same motor.

I compared the center section of the buick, and the pontiac, but i cant see any difference between the two.

i did use the gaskets for the pontiac, and they appear to be correct. all the holes for idle circuit aligned.

I know i am not seeing the problem.

 

if any one has done this (other than Jim Hand) or can lend advice, it would greatly appreciate it.

[Cliff Ruggles]

The Buick large casting center section is not the same or compatable with a Pontiac from the same period.  It requires a few simple modifications to work with a Pontiac airhorn.  They also used APT in the baseplate of the Buick carburetors, so it will need a custom jet/metering rod package as well, if using the Pontiac throttle body.

If you have one of our books, the idle system layout is well explained there, as well as what would be needed to make it work correctly, with photo's, etc....Cliff

[GASGTO73]

Thanks for the reply. I knew something was different. The buick carb was dismantled back in the 90's and stored along with other q-jets of the era (junk yard shopping). I probally have the base and top to match if your book shows that style of q-jet.  I just want to see if the larger primaries of the 800 cfm carb add any more power than the 750 cfm carb currently installed on the car. 

and thanks again for the reply,  Guy.

[GASGTO73]

Mr. Cliff,  i just ran across your 74 Ventura at Pontiacs street performance web site.
 
My hats off to you, It looks awesom. I had not a clue you had a Ventura.
Its good to see true Pontiacs alive and well after 30+ years out of production.
I bought mine in 1989 and got it on the road in 1996.

I noticed the shaker hood on your car. I have same shaker setup on my car but dont have the correct
breather / filter shaker base.
I have looked on line and seen some for firebirds but not shure what will work with a ventura body.

if you or someone on your site might know where I could locate one, (or info on what would work if modified) I would greatly appreciate it.


    And thank you for your time.     Guy.