Quadrajet Throttle Body Casting

[Greg L.]

Happy New Year everyone!

I was wondering if I could have some feedback on what the casting number of the throttle body/base plate is on your original 1968 or 1969 quadrajet. Please also let me know what the carb number is as well.

What I'm trying to determine is what the correct casting number should be for my 29204 carb. I'm thinking it should be a 7037600.

Thanks

[Joe L.]

Re: Quadrajet Throttle Body Casting

Happy New Year everyone!

I was wondering if I could have some feedback on what the casting number of the throttle body/base plate is on your original 1968 or 1969 quadrajet. Please also let me know what the carb number is as well.

What I'm trying to determine is what the correct casting number should be for my 29204 carb. I'm thinking it should be a 7037600.

Thanks

Greg------


7037600 was among the casting numbers used. However, it's very possible that other numbers were also used. In addition, the 7037600 was likely used for multiple carburetor part numbers and may have been machined differently for different carburetor part number applications.

[Greg L.]

Re: Quadrajet Throttle Body Casting

Thanks for your reply Joe and confirming that the 7037600 casting would be correct for my 29204 carb. I realize that not all of these castings were machined the same but I'm told that I would be able to make one work properly for this carb. As the throttle body assy that's with this carb appears to be for a small block I'm told that what I need to do is enlarge the idle bypass hole and of course modify the throttle lever to clear the intake manifold bolt.

I'm still looking for a correct big block throttle body assy but until then it looks like I'll need to use a modified one.

If anyone else has any advice or tips I'd sure like to hear it!

[David M.]

Re: Quadrajet Throttle Body Casting

Difficult to nail throttle body info down for sure. Visual is the only way I know of to see the variability.

Check out this comment from the resident expert on Classic Olds, Joe P:

https://classicoldsmobile.com/forums/general-discussion-33/quadrajet-casting-numbers-149938/

Get Cliff Ruggles on the phone or email him before he retires. Nice guy and he IS the expert on QJets. He may divulge more info?

There are subtle calibration difference due to changes throughout the production run, which wont necessarily reflect in casting numbers. So an early model year 68 (1967) TB could be different from a later. Small block vs big, RPO vs High HP etc...

Verify the date on the TB. This might help narrow it.

Here is Cliffs contact info and float bowl data if needed, just because I have it handy:

https://cliffshighperformance.com/articles/quadrajet-casting-number-chart-1938

Here is where the TB date is: