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-   -   replacing rochester to edelbrock on 350 (https://www.corvetteforum.com/forums/c3-tech-performance/2899807-replacing-rochester-to-edelbrock-on-350-a.html)

Ganey 08-29-2011 08:02 PM


Originally Posted by la1234 (Post 1578552452)
...
can obtain a roachester with holley inside (first time i've heard about it. is that for real??)...any sugestions?

Holley makes a Q-J spread bore replacement carb.

Duals if stock exhaust...

gdh 08-29-2011 09:05 PM

I have to agree with the no Edel camp. If you can get that qjet working properly do so. I have a Holley 750 mech. dp and an Edel 750 mech. dp, a huge step down in power and mpg when running the Edel. I have to rebuild the Holley then back on it goes. What are these new Holleys like?

a1sensei 08-29-2011 09:27 PM

Do yourself a favor, buy a rebuild kit, a gallon of laquer thinner, a metal bucket and a non-plastic brush. Re-build the Q-jet (plenty of help here if you need it). Have the best carb and the satisfaction of knowing you did it yourself.

P.S. Never seek advice from that clown that recommended the Edelbroke carb again!

God bless, Sensei

Jeff_Keryk 08-29-2011 10:15 PM

I just picked up a slightly used Jet Stage 2 Q-Jet. Nice carb. Edelbrocks are OK; an old design (Carter AFB). Holleys are OK too, basically fuel dumpers that are good WOT. Q-Jets are the most complex carbs, and offer the best economy and power over the widest RPM / load range. This is because they are the most efficient. If you want the best street carb, you already have it.

Ralphbf 08-30-2011 06:20 PM

I must just be lucky.

I have a light cam,ZZ4 heads Performer manifold, headers and dual exhaust. Engine had a nice lope at 700rpm but was running lean so it popped and hesitated.

Purchased a Edelbrock 1411.

The lope went away and the power was smooth through 6000rpm.
I also had an Edelbrock on a dodge 360 and it was a great combo.
They are easy to re-jet and are trouble free.

Holley always had power valve issues.
One back fire and they were toast.
I understand that is no longer an issue.
But the carter has always been a stable platform.
That's why Edelbrock choose it.

Can Q-jet out perform it, probably.
Will the carter give you less trouble? I think so.

Ralph

la1234 08-31-2011 02:44 AM

Thanks everyone.:thumbs:
Just found an importer that can bring a Holley from USA.:flag:
Can anyone give me Holley recomended part number (need a 600/ 650 cfm, electric choke, for 350 engine with edelbrock 2601 intake manifold with 4 bbl)?
A.

Clubby99 09-04-2011 05:45 PM

Edlebrock 1406... my best mod ever. Nothing beats the reliability of an electric choke.


Q-jet?:rofl: Give me a break.

7T1vette 09-04-2011 11:19 PM

If you are only interested in WOT power from a carb, you can take about any carb and set it up to perform equally between them...assuming that all have the capacity to satisfy your engine's needs. But, a carb is asked to do much more--like drive in-city traffic, idle well, be economical, etc, etc.

Holleys are good for WOT performance and simple adjustments/changes. Q-Jets are good performers, can idle smooth, transition from primaries to secondaries smoothly AND run more economically than any other 4-barrel carb design. Edelbrocks (old AFB design from the early 60's) are plentiful, relatively inexpensive and mediocre for everything else; they can be tuned for equal WOT performance, however.

If you don't like Q-Jets, are afraid of working on them, don't want to buy Cliff Ruggle's manual for rebuilding and tuning them (less than $20), and have lots of extra money for wasted fuel, spend another $300 for a new [old] AFB carb. Or, buy a $15 manual, a $30 rebuild kit, a $10 brass float and rebuild it yourself in one morning.

The choice is yours, of course....

Ralphbf 09-05-2011 12:16 AM

I guess I have to apologize to the group.

I thought my Edelbrock ran pretty darn good.

Good idle good transition and better gas mileage.

I guess I just need more school n.

rcread 09-05-2011 12:17 AM


Originally Posted by Clubby99 (Post 1578607229)
Edlebrock 1406... my best mod ever. Nothing beats the reliability of an electric choke.


Q-jet?:rofl: Give me a break.

My Quadrajet has an electric choke. And it's 100 times better than your 1406. :D

7T1vette 09-05-2011 10:47 AM

There is nothing "wrong" with an Edelbrock carb (the Carter AFB design). Heck, Edelbrock made Q-Jets in the 80's and early 90's when GM quit making them. But, the AFB design is very 'basic' compared to more sophisticated carb designs.

For those that are "casual cruisers" driving their car once a week [or even less often] and not driving far, the need for a more complex carb isn't there...and it's not as important for having one that is economical, either. And, as I mentioned, the AFB can perform just as well as the others at WOT, if tuned properly. There is certainly no apology necessary for that.

We were just trying to supply the OP with more information about these carbs. His/her driving needs may be quite different from yours and it might be best to use a carb better suited to those needs. Your info and experience with the Edelbrock carb is just as valid as anyone else's. But, with more information, the poster can likely make the best choice for the needs of their car.

Some of us are a little more 'zealous' about Q-Jets because there are so many folks who give a 'bad rap' to it, strictly from lack of understanding. We would just like to provide a different perspective on the Q-Jet carb than what they've absorbed from 'folklore' over the years. I, for one, was not trying to "trash" the other carbs; each has its own merits. :thumbs:

Jeff_Keryk 09-05-2011 11:28 AM

I agree with 7T1 - Edelbrocks, Holleys and QuadraJets will all get the job done, especially at RPM and WOT. But for low end, driveability and gas milage a properly setup QJet is hard to beat. They are the most complex, which can be an issue for most. I, for one, would like to learn more; perhaps become a mini-guru. This is because I love our old cars.

Ralphbf 09-05-2011 12:22 PM

So has any one here set up an Edelbrock on their engine.
I mean set it up not just bolted it on and then replaced it with a Q-jet
what was dialed in?

I'd like to hear this story.

Ralph

a1sensei 09-05-2011 10:03 PM


Originally Posted by Ralphbf (Post 1578613276)
So has any one here set up an Edelbrock on their engine.
I mean set it up not just bolted it on and then replaced it with a Q-jet
what was dialed in?

I'd like to hear this story.

Ralph

I have worked extensively with Holleys, Carters (Edelbrock), and Q-jets. As has been said here before, any can be set to give optimum WOT performance. They can also be tuned down to be more fuel efficient. But no other carb can match a Quadrajet for combining optimum fuel efficiency and WOT performance. They are not as simple to set up, but it is their complexity that makes them able to do what other carbs cannot.

Now I know there is always somebody who will say, "You can do the same thing with a Holley." Anyone who actually understands how the various carbs are designed and how they work know this is not true. No other carb can be as accurately tuned for optimum performance throughout the RMP range as a Quadrajet.

Now, If you have a dragster and fuel economy is not a concern, you just want to quickly tweek you mixture for the next run, trying to squeeze out that extra tenth, you can do that with a Holley in a fraction of the time it would take with a Q-jet. But for any street application, the Quadrajet is best, period. If you don't agree with that, you simply do not know your carbs (sorry).

God bless, Sensei

Ralphbf 09-06-2011 12:33 AM

OKay

I saved the old Q-jet off my 1975 Corvette.
It was so lean at idle it loped.
It was so lean in transition the car bogged down and it popped back through the Carb.

When I put the 1411 on it all the bad went away, even the lope which I miss.

350 new rings and bearings, headers, performer manifold and ZZ4 heads and a Lunati cam.

Advertised Duration (Int/Exh): 262/268
Duration @ .050 (Int/Exh): 219/227
Gross Valve Lift (Int/Exh): .468/.489
LSA/ICL: 112/108
Valve Lash (Int/Exh): Hyd/Hyd
RPM Range: 1400-5800

So where do I start with my old Q-jet.

What jets, which kit where do I start?

Ralph

Clubby99 09-06-2011 02:39 AM

Same old stuff. If original to the car, must be better. Not always true. I ran a Q-jet (recently rebuilt) and an Edlebrock. Not even close. Edlebrock is a better Carb. More power. More reliable. Better gas mileage. I'd like see some factual evidence otherwise. Instead, the same "purists" repeating the same old stuff.

7T1vette 09-06-2011 02:54 AM

No one said anything about "being original to the car", Clubby99. And, since you didn't bring along any "facts"...other than what you have experienced...I guess you don't qualify as an expert, based on your own criteria. Have a nice day.

Clubby99 09-06-2011 03:07 AM


Originally Posted by 7T1vette (Post 1578620057)
No one said anything about "being original to the car", Clubby99. And, since you didn't bring along any "facts"...other than what you have experienced...I guess you don't qualify as an expert, based on your own criteria. Have a nice day.

You are the one that claims to be the expert. Based on your past "purists" posts I doubt you ever ran any carb other than a Quadrajet. I ran both. That is the basis for my opinion. Do you have any independent performance data? Do you have any personal experience? I'd really like to know.

Tim H 09-06-2011 03:57 AM


Originally Posted by Clubby99 (Post 1578620081)
You are the one that claims to be the expert. Based on your past "purists" posts I doubt you ever ran any carb other than a Quadrajet. I ran both. That is the basis for my opinion. Do you have any independent performance data? Do you have any personal experience? I'd really like to know.

Yea , you ask 50 people if a Edelbrock carb is a good one and 49 to 1 says there junk.

jb78L-82 09-06-2011 07:24 AM

I agree that a Q-jet if you can get it to run correctly is a pretty good carb. I am no expert on them since I ditched mine in 1983 (5 years old and 25,000 miles at the time) since it idled very rough (even after trying to adjust it), was hard starting when cold, stumbled on acceleration, and the mileage was atrocious (14 MPG at the time). Since then I have had the Holley 4175 650 CFM spreadbore Vacuum secondary carb and it has been flawless (just rebuilt in Dec 2010 after 25 years of use). The only change I made to the carb when it was new was put in the lightest secondary spring from the Holley spring pack. It starts easily, idles very smoothly (for an L-82), transitions seemlessly to the secondaries, and gets about 17-18 MPG at 65-70 MPH with 3.70 gears with the 4 speed if you drive real nice. It all depends what you want and have access to but the Q-jet can be a good carb but IMHO is overcomplicated for what a carb needs to do and my experience with the Holley 4175 has been really good-easy to tune, easy to rebuild, very good starting and running, good mileage, and seemless transition to power and WOT. just my 2 cents!


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