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Posted by: rey Sep 15 2004, 09:48 AM

Hi All, I have a v8 question.

which 4 barrel carb, Carter afb, Edelbrock performer, rodchester Quadrajet, out of the three which one do you run and why?

My application is for a 283 v8 with mild cam low compression heads.

Posted by: aircooledboy Sep 15 2004, 10:32 AM

John set this rascal up with a Holley 600 cfm double pumper on an Edlebrock Peformer intake, and it seems like the right choice here. Manners for city driving, and a rocket if I want to get on it.

Posted by: jPs Sep 15 2004, 10:55 AM

I don't know about in the teener but I had a Road Demon carb attached to a 350 eldebrock performer intake/cam and liked the hell outta it. So I guess I'm suggesting you might want to look at there carbs too.

Just my two dull cents worth.

Posted by: rey Sep 15 2004, 10:55 AM

Thanks aircooledboy,

sooooo how do you like your v8?

Posted by: propricer Sep 15 2004, 11:10 AM

Regardless of type, a 500cfm is more than enough.
If you question that, calculate the size necessary using the standard equations available on-line.
For what it's worth, I run an Edelbrock 500 cfm on my 327 / 300HP ...
Good luck ...

Posted by: rey Sep 15 2004, 11:29 AM

Thanks Ed.

Posted by: Mike T Sep 15 2004, 12:36 PM

I run a 650 Holley with vacuum secondaries and center hung floats on my 914 with a 305, mid range cam and Edelbrock performer RPM. I didn't consider the others because I use mine for autocrossing and run slicks. I don't know if you can even set up those others to withstand hard cornering. As well as the Holley works I didn't even consider any other carb.

My $.02

Mike T

Posted by: Sammy Sep 15 2004, 01:56 PM

Aren't the edelbrock carbs the exact same thing as a carter AFB, except polished and maybe jetted a little differently to match their intake manifolds and heads?

On mine I used a quadra-crap, I mean quadrajet because they are cheap to buy used and work well. Most guys lean towards holley because they are easier to jet, I learned on a quadrajet so jetting changes aren't that big of a deal to me. Most folks start looking at metering jets and needles and run away screaming.
IMO that is why they got such a bad rap, because they are complicated to jet compared to a holley which has three circuits, idle, main, and flat spot.

I autocrossed mine and never had a problem with G-forces at all.
I used an 800 cfm spread bore, small primaries for normal driving and huge secondaries for that bbbbbuuuwwwwww noise
I ran a 350, so I could use all that. Quadrajets are available smaller, I'd use a 600 minimum on a 283 if I were u.
On a 327 with 2.02 heads and an agressive cam I would go with a 750 vacuum secondary, I know that works great from personsal experience. Anything much smaller is throwing away HP unless the motor is built very mildly.

Take a stock 327 out of a corvette and dyno it with a 500 and then with a 650 or 750, I guaranty you wil lget an increase in hp with the larger carbs and if jetted correctly, no problems.

Also, flow numbers for 4 bbl carbs are usually at 1" of HG at full flow, do you really want to throw away that much HP? In other words, if the carb is rated at 600 cfm, it flows 600 cfm with 1" hg restriction.
At no restriction it would flow much less, prolly around 450 to 500.
That 1"hg of vacuum is a big deal at full throttle, kind of like putting a wood block under your gas pedal.

A little bit of restriction is necessary for fuel metering but the bernouli (sp?) effect in the venturi should do most of that.

No, I'm not suggesting going way too big, but at WOT and high rpm I don't want to have 1" HG in my intake manifold. People spend lots 'o money on free breathing air cleaners and filters, why not match the carb so you can get down to 1" H2O vacuum?

So...........if it were me I'd go with a new edlebrock (carter afb jetted for a chebby instead of a chrysler) or a used quadrajet, leave the holley for...... naw i aint gonna
say it, wouldn't be politically correct. (no offense).

Posted by: ! Sep 15 2004, 03:08 PM

I bought mine with the Quadracrap.....the floats jammed and gas bolied up and over. Bought the Edelbrock carb to sit on the Edelbrock Performer manifold....night and day difference....

Posted by: aircooledboy Sep 15 2004, 03:20 PM

See my signature line and Avatar caption.

Posted by: Andyrew Sep 15 2004, 05:38 PM

I started and ran the car with the Q jet... Doesnt like to idle after a change in throttle.. (ya.. It needs to be jetted)

Sooo We put the 650 Holley on it... Well we thought that it could have been rebuilt.. well... It leaked gas.. Soooo we turned off the fuel pump and checked to see if it would run.. erm..

Backfired.. about 4 feet in the air... then it stayed on fire, then I told him to crank it, and it backfired again and stayed on fire again... So I blew it out (not much I could have done.. lol.

Twas interesting...

Sooo He's rebuilding it...

Posted by: rey Sep 15 2004, 05:42 PM

Keep up the good work, Andyrew .

What Fule pump do you have?

Posted by: Verruckt Sep 15 2004, 05:46 PM

Just my experience with chevy v8s...

Get yourself a 600 Holley vaccum secondary. A double pumper will be overkill unless your cam is big. Maybe you could list your cam specs and comp ratio? Even so, you are in a LIGHT car (dont really need the extra squirters to get moving). You will have better throttle response with the vaccum secondary carb also. I say get the Holley just because..
a) they are dirt cheap and parts are EVERYWHERE
a 6 year old kid can rebuild one in about an hour
c) parts are DIRT CHEAP AND PLENTIFUL
d) a-c

The other carbs you mentioned can be really good carbs. But for simplicity, and reliability and to be able to tune the damn thing, the Holley wins hands down IMO.