Matching QFT 750's

[601HP]

[vector1]

Man that's a lot of carb. Looks good!

[Bernica]

Impressive setup. So....at WOT, you're dumping like 1,500 CFM? Wow!
Like flushing a toilet when you step on it! Have fun!

[ERA Chas]

Thanking you David. Yup, Barry's no dope and makes good stuff happen.

We share a love of standard bore non-stroked SO's. And 2.250 valves. I'd guess you have a little more cam than mine and your CNCs may better my Shelbys a bit. I was at 550HP.

The key is that yours should be seamless throughout the curve. My 600s (improved to 654s) were and are to this day. I went to 37 squirters and it picked-up nicely.

[601HP]

Originally Posted by Bernica

Impressive setup. So....at WOT, you're dumping like 1,500 CFM? Wow!
Like flushing a toilet when you step on it! Have fun!

Well........2x750 doesn't equal 1500 with carburetors. Frankly I don't quite understand why not.

It's time for Brent, Barry or Keith to 'splain it to us.

David

[Gaz64]

Originally Posted by 601HP

Well........2x750 doesn't equal 1500 with carburetors. Frankly I don't quite understand why not.

It's time for Brent, Barry or Keith to 'splain it to us.

David

The engine sees the two carbs as each carb supplying 4 cylinders each.

You'll also note that his carbs are vacuum secondary, so depending on engine displacement, engine rpm etc etc, they may never fully open.

The more carburettors you have feeding the same number of cylinders, the larger the total theoretical airflow needs to be.
Less cylinders drawing from one carb produces more pulsations in the manifold.

Have you seen 6 Stromberg 97s on a Chevy V8 before?

How about the total airflow of a set of 48-51 IDA Weber (about 3000cfm) on an IR manifold? That much carb into a single plenum would be way overkill.