[pontiacphil]

What carburetor (new) would be a good replacement for the factory Quadrajet. My 67' GTO is a factory 400, 360 hp, automatic. The carb. on the motor is a new replacement Quadajet from GM that I installed about 25 yrs. ago. My car sits a lot and it's gotten to the point that I have to "pump" the accelerator 100 times or so (sometimes have to prime with a shot of gas) after it sits for a couple wks. to get fuel to the motor. Put on a new Holley mechanical fuel pump but that didn't solve my problem. I think the carb. is "leaking down" causing my problem. No one in my rural of W. Tn. seems to know how/want to rebuild a Quadrajet. My car is a cruiser/driver that I want to start, run, without a lot of dramatics. I tried a new Edelbrock on another 400' Pontiac GTO I had & was never very happy with it. Is there a good carb. available from Summit, Jegs, etc. that would be an easy, simple swap onto my motor that would be compatible to the original Quadrajet? Any info., or advice will be appreciated. Thanx.

[67GTONUT]

http://www.cliffshighperformance.com/

Do a search on here for Cliff.... He is your man.... send your Q-jet to him, and it will run better then new...

[Ragtop Man]

You answered your own question. A properly rebuilt Q-jet (with all the rest of the motor and trans tuned to match such as fuel system, tank, filters lines, ignition, kickdown, choke, etc) is the answer. Early 'jets have some things that were superseded later and a good xpert will fix them up the right way.

Also, a car that sits a lot may have other issues, like excess backpressure from 'residents' in the system, etc.

Just start at the beginning and work your way back the GTO will feel better than ever if you do it right.

[pontiacphil]

I realize Cliff's Quadrajets are superb carbs. but I need a quick fix at present time and one that my billfold can afford. I was hoping someone might have experience with a replacement type carb. (Holley, Jet, or even one of the Summit remanufactured Quadrajets). Originality isn't a priority to me as my car isn't a show car. I just need a carb. that will bolt to my orig. cast iron Pontiac intake & will start & run like a basically stock 400 motor should. I've got to think that there are people running Pontiac 400's with other than a Quadrajet but I may be mistken. I'm just trying to find some first hand info. from someone who has replaced their Quadrajet with another brand carb.

[mechanic17]

A lot of budgeteers love the squarebore Holley 3310, but you'd need an adapter I think. I have personally used the Holley 650 Spreadbore replacement 4165 and found it worked well, but used more gas than a q-jet, but I'm not a great tuner.

[MCronkGTO]

Your problem of having to pump the gas a lot to get the car started is common with today's ethanol mix of gas. If your car sits that long the fuel is probably evaporating. I have a original AFB 4 bbl on my 67 GP and if it sits for a few days the fuel is completely gone. Also some of the old accelerator pumps seals don't work with the ethanol fuel and you don't get a good "shot". Some have installed small electric pumps in the fuel line back by the tank to "prime" the carb and have found it to start much easier.

I think you will end up having to tune any carb you put on your car to get it to work right. With the quadrajet you know it will work right once it is rebuild for today's fuel.

Mark C

[Engine-Ear]

Originally Posted by pontiacphil

I need a quick fix at present time and one that my billfold can afford. I was hoping someone might have experience with a replacement type carb.

Hold it, Phil! Nothing inherently wrong with your QJ, in my opinion. Your problem seems that gas is evaporating ... Install an inexpensive electric in-line/pass-thru fuel pump and a Filt-O-Reg (or equivalent) fuel pressure regulator and be done with it. Hit the switch to prime the line and the bowl and you're all done.

[67cruiser]

2 areas to start with, flip body of carb. over and you will see fuel wells, are they leaking at all?? time for some marine yex, secondlly accelerator fuel pump well is probably leaking, needs to be reseated with a 3/16 ball. Its the screw next to the power piston area.I spray some fuel or brake fuel in there and see if it holds for a long time, if it leaks out there,s your problem. Thirdly i would run nothing smaller than a 130 seat, if its smaller time to open it up. I personally fill the bronze filter is way to restrictive, iliminate it and ad a inline filter.

[Cliff R]

If money (or lack of it) is driving the decision making process here, I would install modern ethanol compatable parts in your current carburetor, and seal up the bottom plugs while it is apart. Lots of folks are doing this with great success, base on how many books, rebuild kits, and bottom plug kits we are selling.....Cliff

[pontiacphil]

Thanks for all the responses I received pertaining to my Quadrajet questions. I appreciate all the good advice, info., and suggestions that you provided. Now I've got to try to put all this into perspective and figure out the best approach to take. Wish I had the $ for Cliff to rebuild my existing carb. but at present time that just isn't feasible. This site has been extremely helpful to me through the years as it seems Pontiacs are a rare animal here in my "neck of the woods". Chevrolets are dominant, both old & new, with Mopars a close second. It's great that an Internet site such as PY exists and that members are quick to provide informative answers to questions such as mine. Thanks again.

[Ozzmann]

This site has been extremely helpful to me through the years as it seems Pontiacs are a rare animal here in my "neck of the woods". Chevrolets are dominant, both old & new, with Mopars a close second.

pontiacphil at least your in the same country! You try getting advice for these car's in the middle of Queensland, Australia, now that's a effort.
I was asking the same questions a month ago, and have since, have got Cliff's book and have rebuilt my carb, still workong on the tune, but getting there.
Was no more expensive than a new carb, so certainly worth looking at if dollars a tight.

[lust4speed]

With only the carburetor going dry, the fuel pump should top it off rather quickly. Now when the carburetor and the line from the tank are dry, it's going to take longer to suck the fuel from the tank through the lines and fill the carburetor. Just a quick comment on pumping the accelerator - remember that until there is fuel in the carb, you are wasting your time madly pumping the pedal. If the system is properly set up with the choke working properly there is no reason to pump the pedal over one time to set the choke.

I would start with inspecting the short fuel hose that runs from the tank to the steel line. Cracks in this 14" of hose will really slow down the priming process, but might not cause any problems while running because of the speed of the mechanical fuel pump on a running engine. So start with this hose replacement.

If you still have a long wait for the engine to fire up and want a quick fix, install an electric pusher pump back at the tank. Running this electric pump for a few seconds before hitting the starter will fill the lines and the carb - and the engine will fire up as soon as you hit the starter. The pusher pump is only a fraction of the cost of a new carb.

[carbking]

Try this test:

(A) remove the air cleaner, and "prime" the carburetor by adding fuel to the bowl through the bowl vent. Add until you cannot add more.

(B) replace the air cleaner, and attempt to start the engine.

(C) if the engine starts normally, then add a pusher type electric fuel pump as close to the tank as possible.

The volatility of modern fuel is the culprit. Different carburetors handle the volatility with varying degrees of success. Holleys, with the bowls not directly above the throttle body, seem to handle it best; while my beloved AFB's (real ones, not the cheap modern copies) because of the massive aluminum throttle body, seem to have the most trouble. Q-Jets are somewhere inbetween.

Just for the record. The dual AFB's on my 390 will be BONE-DRY within an hour after shut-down in the heat of a Missouri summer. Would need 4 or 5 batteries if I didn't have the electric pump.

And of course (political statement) this highly volatile fuel certainly reduces emissions!

Jon.

[ponchjoe]

Originally Posted by pontiacphil

What carburetor (new) would be a good replacement for the factory Quadrajet. My 67' GTO is a factory 400, 360 hp, automatic. The carb. on the motor is a new replacement Quadajet from GM that I installed about 25 yrs. ago. My car sits a lot and it's gotten to the point that I have to "pump" the accelerator 100 times or so (sometimes have to prime with a shot of gas) after it sits for a couple wks. to get fuel to the motor. Put on a new Holley mechanical fuel pump but that didn't solve my problem. I think the carb. is "leaking down" causing my problem. No one in my rural of W. Tn. seems to know how/want to rebuild a Quadrajet. My car is a cruiser/driver that I want to start, run, without a lot of dramatics. I tried a new Edelbrock on another 400' Pontiac GTO I had & was never very happy with it. Is there a good carb. available from Summit, Jegs, etc. that would be an easy, simple swap onto my motor that would be compatible to the original Quadrajet? Any info., or advice will be appreciated. Thanx.

I'm a little confused. You were asking for a replacement carb for the Qjet. For the cost of a new carb you could get yours out to Cliff for a total rebuild. I'm guessing a new a replacement is 250-300 plus all of the detail parts needed to make it work in place of the existing carb. Call Cliff, buy his book and one of his kits and make it your winter project. This forum has plenty of knowledge and eager people to help you if you get stuck. Cliff is very helpful as well, not your normal businessmen, he actually will help you after the sale!
My .02

[pontiacphil]

Ponchjoe, I have taken yours, and others, advice & purchased one of Cliff's Quadrajet rebuild books. I'm not the world's best mechanic so I've enlisted a young friend (40 yrs. old), that is a good mechanic (primarily Chevy & Holley), to attempt a rebuild. I plan to buy the necessary parts/kit from Cliff's shop so I PM'd him about just exactly what do I need to buy. My existing carb's # is: #17054905 with a 29 77 under that. I also asked him if this particular # carb. is one that is worth rebuilding. Once I hear back from him I will be ordering the parts & start the rebuild when everything comes in. I'm sure I'll be asking more questions, and seeking additional advice, from people here at PY once I "get into" the project. Hope I don't wear my welcome out.

[Engine-Ear]

"Hope I don't wear my welcome out." -p/phil

...I'd say you're a LONG way from doing that. I agree with Ponchjoe's idea of making it a winter project...take your time and ask questions.