Help to choose new carb

[cobra 53]

Using the winter time to do some mods and general works on the car and engine I am looking for a carb change.

Any good sugestions and recommandations?

SBF 302
Heads Ford J302 portet and gasket maching
Intake Ford M-9424 A321 gasket maching
Comp Cam 31-760-8 / 288R-10
Roller lifters
Compr. 10.5:1
Holley 4150 600cfm vac. sec. R80145 / 1993

[Rossba]

I would suggest a 650 DP if manual and you want more power.
I have the same heads with RPM air gap and 35-771-8 running a 750 DP
The airflow through my heads with my cam calculated somewhere around 710cfm
I am making 451hp@6100 with this combination.
What you have should work well.

Check with Holley as they would need more info to help select properly.

[mrmustang]

600CFM Holley Double Pumper O4776C

The 650cfmDP will be a little much for your engine, and will cause stumbling, where the 600DP will give you a crisp, clean throttle throughout your engines power range.


Bill S.

[vatdevil]

Mechanical secondaries....whatever brand/size you choose.

[blown871]

Looking at going back to a carb!!

see link above.

love the carb I got.

[Bernica]

These guys did me right. Patrick is great to work with.

Pro Systems - The Worlds Fastest Carburetors

[4into4]

I've tried a lot of different carbs between two FFR's. Probably the best is to have a carb built to your specs. The best off shelf carb I found was the QFT, vacuum secondary. Like most of the other things on a carb, the vacuum secondaries need to be adjusted for your application, but when it's right, I found that it outperformed mechanical secondary carbs. A light spring/quicker opening rate (logically) worked best. I know that DP carbs are recommended for light cars, but my personal findings were different. As mrmustang mentioned, go conservative with CFM. I have I have a QFT 650, Q-Series on a 347 making 480 hp, and love it.

[cobra 53]

Thanks for all the replies.

I fond on a good Carb Calculator on

Second Strike Carburetor Calculator

Clicking the Help bottom, there are very helpful technik points to choose a carburator.

[Karl Bebout]

Rico, as Bernica said, Prosystems is well worth looking into. Patrick takes all your engine/driveline/location information and will make a carb specifically for your needs. He's exceedingly skillful and his prices are not all that much more than what you'll pay for an off the shelf carb. You won't be sorry.

[blown871]

Love my prosystems carb.
C O M P L E T E L Y
changed my car for the better.

[Bernica]

Patrick will keep your build sheet on file and if you ever have issues, he will walk you through what to do and what NOT to do. If you have an elevation, temp or humidity change wherever you go, he will tell you what to do. He becomes "your guy" for carb issues.