I got ahold of a quadrajet to put on my 3.8buick. I have ported and polished heads, rv cam, headers, and an edelbrock intake. For those with the quadrajet on a 3.8 buick how did you set up the carb to get it to run well on your engine?? I am about to go buy a rebuild kit and was wondering what jets you used and basically how you set the thing up? Thanks.

What is your carb off of? You might be fine (as most people usually are) with just doing a basic rebuild, and NOT rejetting. I've never HAD to rejet, and I've put the same Q-jet on a Caddy 500, Caddy 425, and Chevy 350.....

Besides I've never seen a reuild kit where YOU could pick any jets you want. That would be a tuner kit. (I think that's what it's called)

I got the q-jet of of a chevy 350 from a truck. But cause it's going in a v-6 I just thought I might need to order smaller jets.

Problem with just putting in smaller jets (don't forget the metering rods) is you still have the same CFM carb and all you'd be doing is leaning it out.

Like Cliffhanger said, you'll probably be fine with it the way it is.

If you have the $$$'s get yourself a 500cfm Carter AFB, it's better sized for a V6.

The primary jets are usually ok. I say just rebuild it and see how it is. The secondary metering rods is where you may need to do some tuning. Go to PNP and pull the metering rods out of several carbs and try em. Probably every one you take apart will have different rods and there are several different hangers for the rods too. With some patience you can make a q-jet work awesome and they are the best wheelin carb i've seen. The AFB on the other hand absolutely sucks in the rocks! Stay away from it. (just my .02)

Simple matter of the venturi's being too large. No matter what jet/rod combination you use I doubt you'll get it running right. Heres the qjet you want for the 3.8: Rochester # 17080244

Originally posted by mike
Simple matter of the venturi's being too large. No matter what jet/rod combination you use I doubt you'll get it running right. Heres the qjet you want for the 3.8: Rochester # 17080244

Thank you. I looked up that number....but the listing I have is pretty vague. Just says it comes from a buick engine. You don't happen to know anything about the 2 barrel rochester carbs do you? Just wondering if that might be a better option.

I'm just trying to find something better then my 500cfm holley, and I haven't played with carbs allot yet.

Originally posted by toymaniac


Thank you. I looked up that number....but the listing I have is pretty vague. Just says it comes from a buick engine. You don't happen to know anything about the 2 barrel rochester carbs do you? Just wondering if that might be a better option.

I'm just trying to find something better then my 500cfm holley, and I haven't played with carbs allot yet.

Yeah, its a pretty vague carb in many ways. It was only manufactured for a couple years, then went to a computer controlled version (bleh!) its Tomco part # is 4-318. You're looking for a late 70's skylark and rivera coupes with a 231 and a 4bbl. Even the century had a few. Good luck. I broke down and ordered one in the end. 2bbls I know very little about.

If you're after a 2-bbl with all the good features of the Qjet, get one that has "Dualjet" cast into the body. This is the front half of a Quadrajet, they just omitted the secondaries. These have the same excellent float bowl design and use all the same parts: power pistons, springs, rods, jets, etc. There was also the Rochester 2GC, but these were based on the 4GC (go figure :rolleyes: ) which was the Q-jet's predecessor. Float bowl design not as good for offroad, and a pain in the butt to get the float levels right. Again, look in the late '70s on most v6's and small v8's - 301, 305 etc. To the best of my knowledge the Dualjets were all based on the same casting. A Dualjet would give you all the same good features of the Qjet, except high-rpm airflow. If you don't plan to go over 4500-5000 rpm you'll never know the difference.

Originally posted by Lloyd
If you're after a 2-bbl with all the good features of the Qjet, get one that has "Dualjet" cast into the body. This is the front half of a Quadrajet, they just omitted the secondaries. These have the same excellent float bowl design and use all the same parts: power pistons, springs, rods, jets, etc. There was also the Rochester 2GC, but these were based on the 4GC (go figure :rolleyes: ) which was the Q-jet's predecessor. Float bowl design not as good for offroad, and a pain in the butt to get the float levels right. Again, look in the late '70s on most v6's and small v8's - 301, 305 etc. To the best of my knowledge the Dualjets were all based on the same casting. A Dualjet would give you all the same good features of the Qjet, except high-rpm airflow. If you don't plan to go over 4500-5000 rpm you'll never know the difference.


Hay whould that carb work on a 304 V-8 2bb that rearly goes to 4000 RPM?

Yes, and it'd be a good choice, but there is one issue. You'll probably need an adapter plate, since these have the small bolt pattern and I think your engine has the large one. A better choice would be the Motorcraft 2100; these should bolt on directly. They have at least as good a float bowl design, and the jets are in the back of the bowl so it doesn't starve for fuel when starting a steep climb. You should be able to find one of these on almost any '60s or '70s Ford/Lincoln/Mercury V8 that came with a 2bbl carb. I'm sure that there are pictures of them on the 'net; the front part around the float bowl just looks like an aluminum box with the lid screwed down onto it. The 2100 will give you better airflow (larger bores) than the Dualjet. The 2100 is at least as good an offroad carb as the Quadrajet; and for a 304 that doesn't go much over 4000 rpm it'd be awfully hard to beat. They're extremely simple, and very easy to work on - you can take the top off and adjust the float level with the engine running.

cool, I have a Motocraft on it now witch one I dont know, but it sounds like the one you discribed. So far I like it I went up a little hill just about in my back yard and its quite steep if you stop on it and thats just what I did and it held an idel fine. So far happy with it. and havent had an roblem. I was just wondering about the Q-Jet.

It was a direct bolt on and I got a 3/4" spacer under it

Went out and had a look and on it tag it says


Motocraft

D3UF TA


:confused:

Sounds like it. Those old Motorcraft 2bbl. carbs are all pretty much the same. If you've got one, you're not going to improve on it much by any means. I've had one or more of those carbs on a vehicle for most of the last 20 years, and some Rochesters too. Chances are that the only problem you might ever have with the Motorcraft carbs is if you ignore them for long enough, and they get enough shit in them, the float could hang open (happened to me twice in 20 years) - and that can be fixed with a screwdriver. No other problems. SPECTACULAR off-road performance.

Cool grate news


Thanks :)

I've got a book at home with those codes. Unfortunately it's packed away because we're moving this weekend. D3 is 1973 (C is '60s, E is '80s etc.) and I'm pretty sure that the F refers to a Ford product; the rest would give you model and engine displacement. One of the Ford guys could probably read it in their sleep, but I've not messed with them enough lately to keep that fresh in my mind.

Hmmm grate info.

I'll send it to the ford guys to see if they can De-code it

Kool...I have the power now. I just need to decide whether I want 2 or 4 barrels now.