Carb Suggestions

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Dec 2, 2005 | 11:13 AM

mikea

Thread Starter

Heel & Toe

Joined: Aug 2005

Posts: 22

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From: Macon MO

Carb Suggestions

What Carb should I put on my 69 427/390. It has the original in place and I thought that a new one would improve my performance. The engine is stock with 50,000 original miles. I thought something in the Holley 750 range would be a good replacement.

Dec 2, 2005 | 11:53 AM

Brettmc

Safety Car

Joined: Jul 2002

Posts: 3,770

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From: St Louis MO

I've got a freshly rebuilt Holley 750 double pumper that I need to get off my workbench. It's a 2-corner idle carb that I rebuilt last summer to use while I was modding my Holley 850 DP. It was on my big-block for about 2 months and it prolly ran about 75 miles. PM me if you're interested.

Brett

Dec 2, 2005 | 12:38 PM

comp

Team Owner

Joined: Sep 2003

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From: eville in

keep the orig.

Dec 2, 2005 | 12:53 PM

Gordonm

Race Director

Joined: Dec 1999

Posts: 19,610

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From: Forked River NJ

If you are using the original intake you will need to replace the carb with a spread bore carb. A square bore like the DP series carbs will not fit the intake.

Dec 2, 2005 | 12:59 PM

SHAKERATTLEROLL

Melting Slicks

Joined: Nov 2003

Posts: 2,362

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From: San Antonio TX

If you want a spread bore go to e bay and look for a Holley 6213AAA. It is a 800cfm double pump. I only say this since they are no longer produced by Holley.

Dec 2, 2005 | 01:06 PM

PRNDL

Team Owner

Joined: Jul 1999

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From: Huntersville NC

You might improve your performance by rebuilding and rejetting your original Qjet. Is your exhaust original? The 69 exhaust I think is 2" (can't remember!) so if you want more power your bottleneck is there. Also, if the carb is original to your car, don't lose it! (or sell it or give it away). It is a valuable piece and will be difficult to replace. If you send it out for rebuild make it very clear to the rebuilder that you expect to get the same body back with numbers and dates that you sent out.

Dec 2, 2005 | 01:18 PM

the73vetteman

Advanced

Joined: Aug 2005

Posts: 50

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From: Michigan

Stolen from www.holley.com :

Quote:

QUESTION How do I tell what size carb I need?
ANSWER You take the engine cubic inch and multiply by the maximum RPM and divide by 3456. If you have an automatic transmission you will need a vacuum sec. carb, a standard transmission can use a Double Pumper carb.

I'd vote for keeping it original. However, if you want extra HP check out the tech info on the Holley website. Here's a link:

[URL=http://www.holley.com/data/TechService/Technical/Carburetor%20Quick%20Reference.pdf]

John

Dec 2, 2005 | 04:15 PM

mikea

Thread Starter

Heel & Toe

Joined: Aug 2005

Posts: 22

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From: Macon MO

My 69 has the original exhaust. I figured my original carb could be improved upon. If I could re-jet or improve it....I agree that would be the best. I had no intentions of getting rid of the valuable origianl carb. My intake is the stock one along with everything else on the 427. Someone said that my stock exhaust was my choke point...How about chrome Hooker side exhaust on my C3. My 65 has factory side exhaust and I love it......The big block might come to life with the Hooker set up......