[kingbuzzo]

Hi fellas:

I have another thread going to track down a 70's carb as Cliff told me the carb that came with the car is of a cheby variety. I also have a vacuum leak so it seemed like a good time to rebuild or replace it anyways.

Anyway, he mentioned that the pontiac qjet is a different beast with the hoses on the other side and some kind of vent on the front.

He also mentioned that a 75 or later would have a larger oriface so I was wondering if whoever stuck the cheby carb in there butchered or made his own shaker base (that I have today) so maybe the pontiac q-jet won't fit it?

Can you tell by the pictures if I have the proper shaker base or will run into problems or should I start looking for a different base?

Thanks!

[kingbuzzo]

Photos hopefully rite side up

Sent from my Surface Duo using Tapatalk

['ol Pinion head]

Aircleaner base is correct 1 1/2" drop for your '74. Shaker top came from '74 GTO but is dimensionally the same as '73-76 T/A, have several of each style.

For a Qjet, unless you've changed to an earlier intake like a '72, or '71 & earlier intake & matching ex crossover heads, I'd prob go with a '77-80 800 cfm Pontiac Qjet to rework Am not a big fan of the early integral choke 750 cfm Qjets like the 7043262, 7043262, the latter being what came on your '74. They can be gone through & reworked though.

[unruhjonny]

it looks like a plug was added to the base;
1971-1979 Pontiac Quadrajets all have a "chimney" fuel bowl vent that protrudes into the air cleaner;
Chev carbs don't have this - which is probably why that plug was placed there.

1975+ Pontiac Quadrajets do have the "chimney" in a different spot than the 71-74 units - so a 1973-1974 air cleaner base might be best matched to a pre-1975 Quadrajet (otherwise your valve cover breather tube won't reach the hook up spot).

Something worth mentioning is that 1973-79(?) Pontiac Quadrajets can change from a heat sink style choke to an electric choke;
You just swap the element, and cap off the feed line.

[kingbuzzo]

Originally Posted by 'ol Pinion head

Aircleaner base is correct 1 1/2" drop for your '74. Shaker top came from '74 GTO but is dimensionally the same as '73-76 T/A, have several of each style.

For a Qjet, unless you've changed to an earlier intake like a '72, or '71 & earlier intake & matching ex crossover heads, I'd prob go with a '77-80 800 cfm Pontiac Qjet to rework Am not a big fan of the early integral choke 750 cfm Qjets like the 7043262, 7043262, the latter being what came on your '74. They can be gone through & reworked though.

Oh interesting...50 years of hijinx gets me to this point I guess 😞

I'm not sure what intake I have but it's a 74 SR block with an iron stock one.

I've never had a working choke on any pontiac so that would be a huge upgrade.

[kingbuzzo]

So in your opinion would the '75 & up carb chimney fit in that hole that is plugged and other than re-routing the lines I should be good in regards to the base?

[65 Lamnas]

Pictured are the 2 different styles of "chimney vents". The 71-74 style is cast into a removable cover. Through '72 they have a divorced choke and the 73-74 have an integral hot air choke. The later 75-79 style of "chimney vent" is integrated into the airhorn. There is a 2nd style of 800cfm Pontiac Q-jet that has no "chimney vent". It was mostly used on the 301 engine and is an 800cfm carb. I prefer to use these cores for HP builds due to the lack of the vent.

[unruhjonny]

I might have one of those 301 carbs too!

[kingbuzzo]

I think I found a '75 carb one town over...pick it up on tuesday

Then I guess it'll be an OJ situation with the base:



Interesting how many different q-jets and chim-chim-chimineys there are...I had no idea...always learning