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I have a "Carter for GM" carb on my existing setup, as it came to me. Number 7044226, with K3 DT underneath.
What are the specs on this carb? I will probably get a modern carb for it, a la modern intake manifold and cam, but I would like to know what the specs are on this one, in case it would work.
I have found reference to it, but nothing which even suggests what the CFM rating is.
Last edited by CosmicRay; Jun 11, 2020 at 05:32 AM.
There is no significant difference between the Carter and the Rochester Q-Jets of the same GM part number. They were just built by different factories. Rochester ran out of production space, as that carb was being placed on nearly every 4-bbl application in GM's car lines. If that carb has not been brutalized by shoddy rebuilding in the past, It should be a good candidate to put back on the car. Many of the "modern" carbs of today are really re-pops of old carbs of vintage PRIOR to Quadra-jets. The old Carter AFB design is Edelbrock's main offering for a 'modern' carb. It is a very simple carb and much inferior to the Q-Jet design for many reasons. However, it is plentiful and seems to be adequate for many car enthusiasts.
Everyone should do what feels best to them; but I wouldn't put a 'modern' AFB carb in place of a Q-Jet....even though some folks will look at it with disdain (because they know nothing about it).
Here are a couple quick pics, since one of you asked.
Thanks for the thoughts on the carbs. I think this one has a few problems, but it's possible when the previous owner did some work, they didn't fully tune it. I noticed it's for a different engine than my 454.
I'm no expert, but that looks like a commercially rebuilt Q-Jet. You might want to email @lars for a second opinion, but he may say that carb is not worth fixing.
Here are a few (of many) threads worth reading on this topic.
From: At my Bar drinking and wrenching in Lafayette Colorado
Originally Posted by Bikespace
I'm no expert, but that looks like a commercially rebuilt Q-Jet.
You're absolutely right. It's a hacked, destroyed commercially built carb, best used as a door stop. Right off the bat I can see the secondary airvalves are screwed up somehow, which is probably a good indication of the condition and setup of the rest of the carb.
Bike, thanks for the thread suggestions. I'll peruse them.
Lars, thanks for that assessment. I was already leaning heavily towards another carb, and I had noticed I was having a hard time getting the proper adjustments, and even my mechanic buddy told me something wasn't working right in the secondaries. It just doesn't have the punch a 454 ought to. Since I had already planned to do a little upgrade to the engine, I figured there was no reason to keep messing with this one at the time; either repair, later, or replace.
Since we're discussing, what carbs might you recommend for a 454 which I mostly want as a driver with off-idle performance (none of the high RPM stuff for racing)? I'm currently eyeing an Edelbrock 2161 intake with the 2162 cam (which I understand should fit under the 74 hood with the right air cleaner). My friend is suggesting a 650, since I'm not looking to spend lots of time at high RPM. Your thoughts? And can I get the cam in without lifting the engine?
You dont lift the engine you remove the radiator.
Did your buddy try adjusting the tension on the secondary air valve that appears to be not fully closed?
About 7/8 of a turn from fully closed of the spring tension lock screw would be a good starting point.
Mel, we didn't go very far with the carb. By the time I thought to revisit it, I was already looking into buying something new. Pretty much confirmed by what I read here. My only real interest in this old carb is in whether I could sell it or not. It's not a big deal, as now I'm focusing on the next steps, such as new carb, intake and cam.
Carter carb info?
