I have read about the quadrajet and would like to know how to identify the best one out there.Also what year car or truck they came on. I will be putting one on a 388 with th400 tranny, I have a new eldebrock 750 but the older quad might work better? The car will be 90 camaro and I am planning on stripping out all the comp stuff. Thanks Dusty

 

the quads came on old GM vehicles, i dont know much about them but i hear the have a lot of tunning abilities.

 

Best carb ever made? Holley 4500.

But in reality a carb is just a chunk of metal that meters fuel to control A/F mixture. So the reality is unless your carb of choice is undersized and choking the motor off when tuned properly you are going to see little difference in performance. ie. either carb will work just fine.
Edelbrocks(carter) and Q-jets are fairly simple to tune.

 

the Q-jet and most Edelbrocks are the same thing, the Edelbrock performer 600cfm on my car is Very easy to work with/tune.

 

The edelbrock performer/carter afb made by weber is nothing like a quadrajet, edelbrock used to offer a q jet replacement which was very similar.

the best carb ever made is the dellorto DHLA tri jet

 

Now you know why my post count is so low.... sorry i understood the parts to be the same

 

Edelbrock quit making their Q-Jet model around 2005 or so. They bring a pretty good price on ebay when you see them on there.

Quadrajets are good for gas mileage on a musclecar because when just cruising around, the primaries are at least as small if not smaller than on a two barrel carb, but when you kick in the secondaries they run very well. People are making big horsepower in street/strip cars with Q-Jets. In all out racing you can probably get more out of a big Holley but for the average guy a Q-Jet is a good choice PROVIDING it's in good shape and set up well. If you've got an old worn leaker,you will have a bit of sorting out to do. While they are a bit complicated, you don't have to get really crazy to get one running nicely, just a fair amount of mechanical skill can get one in good running condition.
Check out Cliff Ruggles' book about building performance Quadrajets, he has a web site too, I think it's CliffsPerformance or something like that. Ruggles, the carb shop and a few other places have the good performance upgrade parts fo them, standard common sense stuff like the proper high flow needle and seats, good O-rings and seals for the new trash gasoline, floats, secondary cams, choke pulloffs and etc.
I've rebuilt one, rebushing the primary throttle shaft bores and a few other small tweaks and I'm very happy with it.

I think mid 1980's big block truck carbs (as well as some others) are good candidates. Down in the primary venturies there is a bulge that shows up on the larger 800 cfm carbs.

 

I thank you all for your responses. I will be going to a junk yard this weekend to try and find a quad. Since you all agreed either would work if tuned right I will try both if I can find a quad worth rebuilding.

 

good luck, let us know how it turns out

 

Aren't the same but there are definate similarities. They are more similar to each other then either is to a holley 4150.

 

U would have loved to be in kc mo over the summer. Found a brand new Quadra-junk in the junk yard. Wonder if I will ever forgive myself for not getting it, but I was with friends that wanted to go . Good luck. Oh it may be a tip but it was on a old school pimp my ride type of car. U know 4 colors of candy paint etc.

 

I found a quad today on a 85 iroc the # 17085204, 3344-hzj. Does anyone know if this can be used without a computer? Or what would it take to make this quad work since it had some wires going to top left side and some sort of plug on right side. Thanks

 

i would think it would be able to be used without a computer.

 

That is a "electric" q-jet aka a CCC carb (computer controlled carb) as called by GM.
Used on many different GM v-8s in the 80s.
Have one on my 84 HO.

As far as being stripped of the wiring/elec. stuff and being used I can't tell ya!

 

Without a computer to run it, it would have one mode where it ran "right" - wide open.

 

I ran my 84 HO without the computer plugged in as connectors got cut in the past, original CC carb, non-CC distributor. It ran better than with the Holley 4777-7 650cfm that was on it before, but tended to stall at low rpm (kinda scary when the engine stops when driving).
If you still have all the original components, you will have to plug in everything for it to work properly.

 

The best Qjets to work with for a modified engine are the pre-emmitions or early emmitions carbs... like say '68-72. They are the most 'versatile' in my experience.

My favorite of all the carbs I've used though was the 3310 Holley. I never should have sold that. That was the one I liked the most.