Want To replace carb, what size should i replace it with?

[longdillon1]

Hello. Looking to replace factory carb on my 75 vette. Leaving it pretty much stock until it blows then Ill put new heads and cam. But for the most part now, I want a reliable carb for an everyday driver. What size edelbrock carb should I get 600, 650, 750? Will I have to change my intake or should I? If I do will I have to replace my cam and heads?
Thanks Again,
Dillon

 

[Rodney Gold]

I would suggest a holley 600 over an edelbrock , its easier to tune to the nth degree and you can get jets etc just about anywhere. If you go edelbrock , the 600 should be fine , get the non economy 600 as it runs a little richer , the economy one is tuned lean and would require a kit to set to "stock"
If you want more oomph , then a cam and head change is the answer , the 600 will perform ok on a moderate power hop up. If you are intending to do all that , I would go with an edelbrock "kit" , heads , cam , lifters ,intake , carb etc all in one and matched.
Performer is probably the best if you dont intend to put in a higher stall torque convertor...if your car is auto. For more power and power higher up in the rev range , a performer RPM.
Rather be more conservative on carb and cam selection for good driveability ...the old maxim "all cars want less carb and cam than their owners do" still holds.

 

[longdillon1]

what model# is the "Non Economy" Edelbrock carb? I am fairly familiar with edelbrock carbs. Can you point me in the right direction? Maybe a edelbrock intake and carb set of part #s?
Thanks Again

 

[Vettehead Mikey]

Your stock carb is a 750cfm qjet. Why are you replacing it with something smaller?

Swapping carbs will not give you more power if that's what your after.

 

[Rodney Gold]

The 1405 is the one calibrated for performance
Edelbrock.com - Carburetors & Accessories - Performer Series Carburetors

Total package - performer
Edelbrock.com - Performer Power Packages - Idle to 5500 RPM
Look in the chev section for the 262-400 V8 1957-86 bits

 

[Hib Halverson]

Your best bet for that 75 is to remove the stock Quadrajet, rebuild it and later, for high-performance use, alter the tuning, if necessary.

For street use on stock and mildly modified small blocks in C3s, the Quadrajet, with proper tuning, is the best choice for performance, by far.

The Edelbrock AFB "clone" is a poor choice because of it's float chamber design is not good on cars which get driven hard under braking. That's one reason GM discontinued using AFBs on Corvette in the mid-60s.

The Holley is an ok carb but, compared to the QJ, it gives away a little gas mileage along with some tuning flexibility. That said, on engines making over 400-425hp, the Holley becomes a better choice.

 

[Bill75]

Your best bet for that 75 is to remove the stock Quadrajet, rebuild it and later, for high-performance use, alter the tuning, if necessary.

For street use on stock and mildly modified small blocks in C3s, the Quadrajet, with proper tuning, is the best choice for performance, by far.

The Edelbrock AFB "clone" is a poor choice because of it's float chamber design is not good on cars which get driven hard under braking. That's one reason GM discontinued using AFBs on Corvette in the mid-60s.

The Holley is an ok carb but, compared to the QJ, it gives away a little gas mileage along with some tuning flexibility. That said, on engines making over 400-425hp, the Holley becomes a better choice.

I agree w/Hib on everything above except for the part about reusing the 75 Q-Jet later for performance. The 75 has an altitude compensator in it (Aneroid) and they are very difficult to tune for performance. I would check the carb ser no and make sure it's a 75, if so get a 76,77 or other suitable year to modify for performance. I had the same issue with mine, put it on the shelf and reworked a 76. I tuned it for performance using Cliff Ruggles book as a guide and it works like a champ!

Bill

 

[gmjunkie]

Your best bet for that 75 is to remove the stock Quadrajet, rebuild it and later, for high-performance use, alter the tuning, if necessary.

For street use on stock and mildly modified small blocks in C3s, the Quadrajet, with proper tuning, is the best choice for performance, by far.

The Edelbrock AFB "clone" is a poor choice because of it's float chamber design is not good on cars which get driven hard under braking. That's one reason GM discontinued using AFBs on Corvette in the mid-60s.

The Holley is an ok carb but, compared to the QJ, it gives away a little gas mileage along with some tuning flexibility. That said, on engines making over 400-425hp, the Holley becomes a better choice.

As for Holley..........................
Trusted name of automotive "Arsonists" for over 50 years!!

 

[Bob Chadwick]

As for Holley..........................
Trusted name of automotive "Arsonists" for over 50 years!!

You crack me up Junk.

 

[Copdogcorvettes]

Well if you are looking for an Edelbrock, I started cleaning out my shop and have one in bolt on condition. I purchased it to use and then found the problem with my Holley spreadbore. So I don't need it any more; Make a good deal.

Gary

 

[XS-Style]

Well if you are looking for an Edelbrock, I started cleaning out my shop and have one in bolt on condition. I purchased it to use and then found the problem with my Holley spreadbore. So I don't need it any more; Make a good deal.

Gary

Ive been looking for a replacement carb for my 75 as well. After 100K+ its catching some age. So of the OP passes, shoot me a PM

 

[Hib Halverson]

http://www.corvetteactioncenter.com/forums/c3-technical-performance/


As for Holley..........................
Trusted name of automotive "Arsonists" for over 50 years!!

:D[/QUOTE]

Well....I often agree with the ole junkster, but on that we disagree. No Holley has ever set a car on fire but users have done so, either through stupidity, inatttention, lack of maintenance or improper tuning technique and those cars have happened to have a Holley carb.

 

[Copdogcorvettes]

I may be old school but, I really like my Holley carbs. They are very easy to tune, repair or rebiuld. For the corvette the spreadbore works great. The only problem I've found is getting small parts for some of the older models. Summit racing and Jegs now has most anything you would need.

Gary

SAVE the WAVE

 

[baxsom]

i think its hilarious when people say that since the stock qjet was a 750 then you should get a 750 in a holley or other square bore. do you think for a minute that his engine ever used all of the cfm that the qjet was capable of. that is the nice thing about a qjet it only uses what it needs.
thats the reason why gm put so many 750 cfm qjets on a lot of different types of cars. in fact a recent issue of hot rod magazine shows an inline 6 pontiac with a 750 qjet 4bbl on it. would you put a 750 holley on that one as well?

 

[gmjunkie]

Well....I often agree with the ole junkster, but on that we disagree. No Holley has ever set a car on fire but users have done so, either through stupidity, inatttention, lack of maintenance or improper tuning technique and those cars have happened to have a Holley carb.

Your probly right on that Hib!! But every New Holley I ever bought I had to tear apart and clean the metal shavings out of it,Screw with it all the time and I hate the gas mileage!!Give me a Good Q-Jet or Good Carter AFB and I'll STFU!!

 

[longdillon1]

So from what Ive heard my carb is just fine. Maybe I need to tune it up. Oh and by the way, I was only putting a 600 cfm on it because I thought it was stock that way. I just rebuilt the carb and it works just needs to be tuned. anyone know where I can find the specs?
Thanks

 

[JimBobC4]

" The Edelbrock AFB "clone" is a poor choice because of it's float chamber design is not good on cars which get driven hard under braking. That's one reason GM discontinued using AFBs on Corvette in the mid-60s."


I just had to jump in here ....

I had an Edelbrock performer carb on a decently modified Rustang and during very heavy braking or in a very hard turn (SCCA autocrossing) the car would cut out. Edelbrock even has a mod to try and resolve the issue if you call the help line. It helped but did not cure the issue.

Otherwise the carb worked really well but I did have to buy the kit to tune it. Out of about 10 installs I've seen only 2 work correctly out of the box.

As for the Holley, I've seen more than one dirt track car go up in flames due to a cracked base, leaking bowl, a loose or missing float level screw, and a bad gasket after a rebuild.They work well just be careful if you like to tweak on it.

 

[Copdogcorvettes]

Well, Just my .02 worth. I've been running Holley carbs for over 40 years on Fords & Chevys. Street cars, off-road 4X4s, Sand Draggers and so on. I've never had any major problems with them. I've done complete overhuals at the track in less than hour.

So, it is just what you are use to. Don't get me wrong a good working well tuned Qjet is a very good carb.

Gary

SAVE the WAVE

 

[baxsom]

. Don't get me wrong a good working well tuned Qjet is a very good carb.

Gary

the problem is trying to find someone that can tune that qjet to your car.

 

[Bill75]

the problem is trying to find someone that can tune that qjet to your car.

Cliffs High Performance Quadrajets :: Qjet Carburetor Rebuilding, Bushing Kits and Parts

You can buy this guys book and tune it yourself or talk to him about your application and he'll do it for you. I reworked mine to his book and I'm real happy with the performance.