Hello, I have a 75 base vette with a 4 speed, the original Rochester Quadrajet is giving me a fit, won’t come down off fast idle. I would like to replace it with a Eldelbrock carb, which one would you recommend? Thanking you in advance !

 

IF it's the original Q-Jet (#7045223), send it to Lars. If it's not the original Q-Jet, post a photo of it to see if it's worth rebuilding.

 

Yes, it is the original carb, car only has 66k on it, I was thinking the Eldelbrock may give better performance and fuel economy, thanks for the input

 

Edelbrock “performer” carbs are nothing more than a remake of a Carter AFB, a carb deemed obsolete in the mid 60’s. Since it has a square bore mounting pattern it won’t fit on your original spread bore intake manifold without an adapter, making its fuel emulsification abilities go from bad to even worse. It would be a downgrade in both performance and fuel economy.

+1 for seeing if your Quadrajet is suitable for a rebuild. There’s no better carb for a stock to mildly modified engine in these cars than the one that came on it.

 

Thanks! Now I have to see if someone in my area can rebuild it!

 

Sorry to tell you, but don’t let anyone but Lars restore your Quadrajet. If you want to pull your hair out, and throw all kinds of money at your car, then by ALL means DON’T have Lars restore your carb. Unfortunately there are large number of people that like to suffer and waste money, I am not one of them. After you visit the Forum for a week or so, you will see all the carburetor horror stories, and believe me they are not made up.
YOU HAVE BEEN WARNED 😬😬😬

 

Thanks, I willl definitely look into that

 

Just search for posts by Lars. There are some horror stories on here about new and "rebuilt" carbs.

 

Q-Jet lars c3 corvette forum threads

 

If your looking to eventually want to be able to clean and maintain the carb yourself then I suggest maybe going to a holley vacuum secondary carb before an edelbrock (Ive had new versions of both). Q jets are great if you dont mind sending it off to lars when you have an issue but most of todays backyard and shop mechanics are not very good with them it seems.

 

Thanks for the heads up, will look into the Holley, have had them before and had good service with them

 

I have played the Carburetor game for way too long on my 1968 427 C3. The C3 had a Quadrajet on it when I bought it and that was over 33 years ago. It was not original to my Corvette so I traded it off to someone who owned a 1969 C3 that needed a correct year carburetor for their beast.

The Quadrajet was "new to me" and I "was dumb to it", a bad starting point for both. I regret not having kept my Quadrajet, but had I still owned it, Lars would have had his chance to "work his magic" and use his awesome expertise!

This led to the Quadrajet being removed and the intake was changed to use a Edelbrock dual plane with a Holley 750 Double pumper which turned out to be restricting my engine so I went to an 850 Custom Holley body that was modified,built, tested and shipped to me byA.E.D. Performance in Richmond, Virginia. They built an awesome carburetor that purred from the moment I started the engine up and was able to flow way almost 1100 cfm and my 427 absolutely "loved it" as it ran even better than it looked. I didn't even have to re-jet the carburetor after installation as they had everything set-up for my unique engine combination.

If you want a really nice Holley then you NEED to call A.E.D. Performance FIRST.

In my collection are the following carburetors: 1-Avanti Modified Holley 750 dbl-pmp, 1- Barry Grant 850 cfm Speed Demon, 1-A.E.D. Performance 850 HO dbl-pmp, 1- Edlebrock 750 with electric choke all gathering dust. The biggest issue was starting my 12.25-1 compression big block when it gets cooler. None of my Holley based carburetors had a choke tower as that is one of the first things they remove. On one of the Holley carburetors I was able to use the choke hardware with the thermal coil. This allowed me to set the choke when cold to hold the engine at a slightly higher speed using nothing but the coil and other parts from a Holley Electric choke kit for a double pumper.

Now my C3 has a simple throttle-body based Holley EFI system on the 427 and it seems more than able to supply my engine using an Edelbrock RPM,Air-Gap intake under it. It is just a tad too tall and stressing the hood over the area. When you open the hood on my C3 you see what appears to be a plain old Holley carburetor sitting on the intake. Holley made EFI system called a "Stealth Sniper" that uses the throttle body turned 90* from the normal Holley Sniper installation. If you get down and look closely you might see the (temporary) fuel pressure gauge attached to the fuel line showing 58 psi as that is a dead give-away that it is an EFI system.

My next plan is to go to a low single plane intake with drilled Injector holes and a Dry throttle body about 2" tall. Using a Holley Terminator Controller I should be able to make it a nice reliable system. I can have multi-port fuel injection like modern engines using a dry throttle body on top of an intake designed specifically for a BB Chevrolet engine and the big ports. The entire system will still be short enough that I should not have any trouble with the L88 Hood and it's air intake system and have the best of both worlds. It seems the most expensive part is the controller that you need to operate the EFI system. Ain't technology great?

 

Where are you located? There still are a few out that that will tackle the Quad and some are pretty good. Maybe not Lars good, but able to do a good quality rebuild that produces good results.
If you are in any way mechanically adapt, they arent that hard and if you wanted to tackle it yourself there are a few good parts sources and plenty people here that could help you walk through it.
The 7 P's apply here.
Prior Proper Planning Prevents Pi$$ Poor Performance.

 

I had my Qjet rebuilt by Lars earlier this year, based on several posts and recommendations from other forum members. Best decision I could have made. The car runs excellent (73 L82). I also set the timing and recurve the distributor as per the white paper also from Lars. Starts right up, idle smooth, good power, overall its a very happy SBC.

 

I’ve heard so many great things about Lars, what does a rebuild cost with him ?

 

Why don't you just e-mail me?

 

Thank you, can you please
send me your email address

 

wht is your email Lars. Thx, Steve

 

v8fastcars@msn.com

 

👍Thx!