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Prescott · 08-13-2014, 10:34 PM

My opinion is this: If you get good at tuning carbs, either of these can be made to work. Edelbrock says that their 600 cfm carb works on a 454, and it's true. The 600 will be easier to tune and run. The 750 will give you a higher rpm range. So lets look at it mathematically.

Your 350 bored .080 over is now a 364 inch engine. Use the basic formula (not counting volumetric efficiency, which will make it smaller) for cfm:

Cubic inches X RPM / 3456

364 @ 5000 rpm is 526 cfm
364 @ 6000 rpm is 632 cfm
364 @ 7000 rpm is 737 cfm

So you can see that it all depends on the rpm you are aiming for. Don't let any of us tell you which one to use. Please do this instead: Buy the metering rod kits, learn how to calibrate these carbs, and try them both. Here's the best part. We get to read about what happened. How about it?

08-13-2014, 10:34 PM	#10
Prescott Registered User Join Date: Jun 2013 Location: Prescott AZ Posts: 31	Re: carb size, 750 or 600?? My opinion is this: If you get good at tuning carbs, either of these can be made to work. Edelbrock says that their 600 cfm carb works on a 454, and it's true. The 600 will be easier to tune and run. The 750 will give you a higher rpm range. So lets look at it mathematically. Your 350 bored .080 over is now a 364 inch engine. Use the basic formula (not counting volumetric efficiency, which will make it smaller) for cfm: Cubic inches X RPM / 3456 364 @ 5000 rpm is 526 cfm 364 @ 6000 rpm is 632 cfm 364 @ 7000 rpm is 737 cfm So you can see that it all depends on the rpm you are aiming for. Don't let any of us tell you which one to use. Please do this instead: Buy the metering rod kits, learn how to calibrate these carbs, and try them both. Here's the best part. We get to read about what happened. How about it?