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quadrajet lovers?????

3488 Views 8 Replies 7 Participants Last post by  jimfulco
i have 350 cid,290 horse,chevy crate motor........what year quadrajet carbs do u like.......serial #s....year applications...recommendations.....source to buy???? dont want to use the eldelbrocks!...... thanks pete!!!!!!!!!!
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FWIW, places like Jet Performance use the late 70's (170 prefix) qjet bodies for their stage 2 units. They drill out and tap the air horn so you can adjust the APT externally. Other than that, they enlarge the mixture screw orifices a bit, plug the idle-air bypass, and they replace the primary jets, rods, and secondary rods & hangers as needed. Mine ran decent out of the box on my old engine (my new 383 required enriching the idle to primary transition circuit, opening up the idle-air bypass again, and larger primary jets/rods).

These later qjets use a different primary rod length than the earlier qjets (and the Edelbrock version, too)... Sometimes parts can be tricky to find.

Cliff Ruggles book is a great resource...
I second that, use a Jet Quadrajet. I`ve heard alot of good about Jet`s carbs. Years ago I ordered a sean murphy Quadrajet, while the calibration was correct the electric choke did not work as well as the main wells leaked down overnight. All the companies say they epoxy the main wells and they do, but 9 times out of 10 they still leak, so what I learned is it`s best to strip the carb down to just the main body and restake the main wells with a punch and hammer. Next sit the carb over a bucket and fill the bowl with fuel and check for leaks and restake if needed.
Sparky's Carb is another very good Q-Jet builder, he'll take your engine specs and build to your application, not just some generic build
quadrajet carbs

thanks for input. just know the olds school carbs ran well when they were right and were prone to leaking. thanks.........pete......more replies??????? :thumbup: :thumbup:
76-84 vans, pickups, and medium duties are a great source for 170-prefix 800 cfm carbs. They all got 800s from the factory, regardless of 305, 350, or 454, even most of the 4.3 V6s had them. but if they were replaced by the dealer they were probably 750s so you have to check. Only way to be sure is to look down the primary throats. Starting in about 84 they went to the electronic Qjet which should be avoided for performance use. If it has an electrical connector on top above the primaries, skip it.

When I lived in L.A. I used to drive down to Jet and stop at a junkyard that was nearby. They had a whole row of trucks and vans and it was almost guaranteed that they had a few 800s I could pull.

I'm a pretty fair hand at setting up a Qjet, but I still use Jet. Well worth the money. If you live in a cool climate, make sure you tell them to keep the secondary lockout on the choke. Its a little cam that doesn't let the secondaries open until the choke is off. Without it in cold weather you get a huge lean bog if you give it too much throttle. Otherwise, I've tried to improve on several Jet carbs and couldn't. They get them spot-on
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Interesting. Sean Murphy was the Qjet guru at Jet before striking out on his own. Wonder why his carb didn't perform ideally?
Well Cool, I guess nobodies perfect. I didn`t bother to mention the replacement he sent me was even worse than the first. After that I just fixed the carb myself and didn`t bother to contact him since when I called him to tell him about the first carbs problems he wasn`t very friendly.
I have the equivalent of the 290hp 350 in my '72 Nova, and it has the OEM Q-jet that came on the car, although rebuilt once at a local shop. It works great. Much better than a new Rochester Q-jet that was allegedly right for the car, and much better than the Holley Spread-Bore I tried back when I thought Q-jets were junk. It works so well that I ran it with the accelerator pump disconnected for a couple of years with no problems. Part number is 7042203 for manual trans (no provision for kickdown cable attachment).
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