I’m tired of the fight and I’m looking to replace the factory original Qjet on my 85 LG4 TA. Mild cam (204/214), 700r4 & 3.42 gear.

I’m going to be adding Vortec 305 heads and I want the fuel system dialed first. Currently there is an Edelbrock 2101 Performer intake (dual pattern) installed.

I’ve purchased 3 more Qjets in the attempt to keep this one alive, by the time I ship it/them to a competent builder and have it gone through and tested I’ll be near to the cost of a new carburetor and still be working with 40 year old carb that’s been man handled.

From my own research, the Edelbrock AVS2 1903 500cfm should be in the neighbourhood of fitment.

Anyone gone this route?

 

I'm not particularly a fan of edelbrock carbs. Not the worst thing on the planet but leaves much to be desired when tuning. Personally, I'd be looking into a spreadbore Holley. I'm not a huge fan of holley BUT they are very adjustable and parts aplenty. Down side is the cost but you get a way better carb.

 

I applaud your effort to keep the quadrajet all these years. I understand though that sometimes you just gotta try something else. I have run an Edlebrock on my LG4 for about 14 years now. It's been okay, but like anything has had its quirks and I'm ready to try something else too. Someone on these forums highly recommended the Street Demon 625. I bought one but haven't installed it yet.
https://www.ebay.com/itm/35560825610...3ABFBMroXgk-Jj

 

My '89 Camaro had and Edelbrock carb (and intake) on it when I got it, and one of the first things I did was get rid of it. I never could understand the logic of replacing a technologically advanced (for it's day) spreadbore carb for a squarebore design that dates back to 1968. The Carter Thermoquad carb was even better than the AVS: people knock the Thermoquad for it's plastic fuel bowl, but as long as it wasn't cracked that helped keep the fuel cool.

As far as Quadrajets go, they definitely have their unique quirks - practically every type of carburetor ever made does. I'd say all the problems that people complain they have with them are due to them not being adjusted properly, or having worn out throttle shaft bores causing vacuum leaks.

 

I would not use that carb, if I had my pick I would send off the Qjet to a reputable builder. There is nothing wrong with that carb it should idle run and do the job but will probably make less power and less MPG than a well running qJet

 

Hmm. Old thread.
Running CCC with EGR disabled presents detonation and mileage loss. (I am assuming you didn't bend over backwards to run external EGR given your intake.)
CCC can easily handle your cam.
Staying on topic, the Vortec 350 I owned briefly pulled 26mpg hwy and ran tip top with a stock ECM, EGR, and my 86 L69 Q-jet.