The Stovebolt Site Forums The Shop Area The HiPo Shop Quadrajet...rebuild or replace?

My son and I spent all weekend pulling a 350 out of a wrecked '79 Silverado with the intention of putting it in the '63 C-10. A pleasant suprise was the Rochester Quadrajet sitting on top of it (once we removed all of the junk). It appears to be in OK condition except for the dirt dobber nests built all over it. My question is should we rebuild it (or more accurately...have it rebuilt) or should we replace it with something more along the lines of an Edelbrock performer.

I'd like to have the performance of a 4 bbl, but don't want to be adjusting it all the time like I've heard is required for the Hollys. We aren't planning on building a racer, just a slightly warmed up street truck.

I would rebuild it or have it rebuilt.Carb king where are you???The Q-Jet is a good carb if set up properly.Take the numbers off the flat boss on the pass side(example 17079112)and get a kit if you do it yourself.Good Luck!

gtow69,
Thanks for the response. That was my first inclination, but thought I would check with the "tribal elders" first.

By the way, if Carb King ever shows up the numbers I found on the carb were 17059206 and then under that was 2848 CBF.

Texmo, that number looks like it might be computer controlled. I could be wrong but I seem to remember that carb numbers begining with 1 indicate computer. Run that by Carb King or a good carb man. I haven't dealt with one yet, but if you don't need it.

Larry

The 79 would not be computer controlled & is the best carb to work with. They run great when they are done right. The Edelbrock performer is good right out of the box if you don,t want to tackle it. The Q-jet will get better mileage.

Thanks for the info. Any idea on a ball park figure for someone else to rebuild this carb? I could probably do it but would be less than confident in the results. The volume of my experience is with diesel engines (no carb required;)) and is more than a day or two old.

i plan to let jet performance rebuild mine.you tell them what you have and they rejet it to work best.

I bought a rebuilt Q-jet for my '83 Jimmy from Forbes in Fort Worth. Price was $165 exchange in Jan. 02. Bolt on and go, no problems.

817 332 7643

Quadra floods are great carbs. They have some quirks that will need attention like the casting plugs that will need to be resealed when you overhaul it. Oh and the instructions in the kit won't tell you how to seal them. I tap them in a little more with a small hammer and seal then with JB weld. I have heard that fingernail polish will seal them as well. Seems fingernail polish wont come off with gas or so I am told. Anyway, if you can read you can o/h a quadra flood.

Texmo,
Go to http://www.corvettefever.com/howto/53360
A lot of good pics on rebuilding a Quadrajet.
With your back ground it will be a piece of cake
to do the job yourself.

Arnie

I'm running a rebuilt Q-jet on my '62,and it's working fine. The biggest problem (and the most common) I've run across with Q-jets is the throttle shaft getting worn sloppy,causing erratic idle,gasoline leaks,bad mileage etc. Be sure to have that checked and have it re-bushed if there's any looseness. It makes a huge difference.
Speed

Texmo,
Look at the secondary metering rods and hangers.These are the 2 hanging down in the back that are held into place with 1 small screw.Look at the 2 holes in the metering rod hanger for wear and the metering holes in the body.If these wear oblong it will cause a flooding situation under hard throttle.If this is the case the carb is junk and no need to buy the kit .

I just received an email asking why I hadn't jumped on this thread.

The answer is very simple: I read the first post, and since I do ONLY 1974 and earlier carburetors, did not again look at the thread. I have NO first hand knowledge of O.E. carburetors newer than 1974, and try to avoid posting if I am not sure of my post.

However, any of the non-computer-controlled Q-Jets may be MODIFIED to work on various applications, and work well. The key here is knowing what mods to make, or knowing someone to make them for you.

A new book just appeared last week on this subject. The book is entitled "How to Rebuild and Modify Rochester Quadrajet Carburetors" by Cliff Ruggles, published by SA Design Books. Cliff has the books available, and may be reached at (740) 397-2921.

The book should answer all questions concerning modification of the Q-Jet. I have a copy, and can recommend it to anyone interested in Q-Jets from a novice to a professional.

Jon.

Jon,
Thanks for the post and the book recommendation.

i have a 59 apache with a bored out 350. I just put a 650 holley spread bore q-jet style replacement on my holley spreadbore manifold and it saves me alot of gas and has shown very noticable horsepower gains over the old edelbrock 600 performer i had. the model # is 4175 and they run about $300 brand new. oh and dont forget to ask from a 5/8 to 3/8 fuel inlet with it.

Texmo

Your carb is a 1979, federal , chevy, auto carb. Carb was built on the 248th day of 78 The letters are a plant code and that I cannot help you with.

Hope that helps to get a carb kit with more than over the counter parts get in touch with The Carb shop in Eldon Missouri. I bought my kit from them and the kit was much better than a over the counter kit.

P.S. buy the throttle shaft bushing kit really it is a must as the stock plate has no bushings and they are prone to being sloppy and creating a vaccum leak.

I have rebuilt qudrajets with luck, but once they get play in the butterflys and linkage points they tend to be junk. For the price, go with a Edlebrock. But I would say the one Cletus listed is a good price.

Being that I like the q-jet and they are not hard to fix. I would buy a kit and the bushing kit and re build the carb. The book that was listed is great I own it 24 dollars worth that and more. The latest book has a bunch of items for upgrades as well. Covers the entire range of carbs in detail. I have a edlebrock 750 sitting on the bench that I was going to use but fixed the q-jet instead. The small primarys are great for normal crusing and fuel MPG . I am sure I could get a better peak hp number with the 750 but being that the truck is a truck with a truck trans ( very slow up shifts) I feel the the stock carb offers better usage under the every day driving.


If you need a edlebrock let me know I will be happy to part with it.

I've ordered the book off Amazon but it was back ordered. Current plans are to rebuild the Q-Jet. My son is itching to tear it apart, but I'm diligently resisting the impetousity of youth until I get my hands on the book...

Thanks for all the help and opinions.

impetuosiity...impetuousity..spelling...not my thing