carbs: More or less? Tell me why.....

[1968-coupe]

Looking at crate engines.

a) Ford Racing 351 stroker, 427 cubic inches 535 hp, tested with 700cfm Holley carb. (or so im told by their tech department that the figures achieved during tests were with a simgle 700cfm carb)
Ford Racing Performance Parts - [Part Details]

b) Edlebrock 347 stroker, 449 hp, uses 2x 500 cfm carburetors.
Edelbrock.com - Crate Engines - Small-Block Ford - Performer RPM Dual-Quad 9.9:1 (449 HP & 417 TQ)

Now my question is why does an engine producing less power need more carburetion? Correct me if im wrong but doenst more power consume more fuel/air?

Ford Racing said an 800cfm was too parge for thier 427 crate, no larger than a 750 carburetor should be used for best results. So why does the less powerful 347 use 2 carbs for a total of 1000cfm flow? I could understand it if the engine was producing more power and thus would consume more air/fuel, but wouldnt the 427 actually use more to produce its power than the 347?

Hopefully someone can explain this to me.

 

[tx65coupe]

The one with the 500 cfm carb actually has 2 of them according to what that says. That doesn't mean you have to run 2 carbs on that motor though. You could probaby run a single 750 or something similar.

 

[1968-coupe]

Yes I know. I was curious as to why and engine producing that amount of power would require 2x500cfm carbs when the engine producing some 55 more hp (at minumum) more required only 1 750cfm.

 

[69gmachine]

The answer to your question is that it doesn't. The two carb E'brock set up is mostly for looks. Not to say that it can't be made to run well, but it is entirely unnecessary to run well.

 

[1968-coupe]

I love the was a tri-carb set up, but the price tag is too much for me, Ill go single Holley 4bbl

 

[rbohm]

three two barrel carbs, or two four barrel carbs are mostly for badassed looks, though they can and do help power output in the higher rpm ranges when properly tuned. the only multiple carb setup that is not just for looks is the weber carb setup where you have one throat per cylinder.

 

[tx65coupe]

Like was already said, that motor doesn't need the dual quads at all. Good choice on staying with a single carb. It will work better and be easier to get it to run right. I agree dual quads and 6 packs are cool.

 

[D.Hearne]

The three two bbl setups work better everywhere in the rpm range. The one I have is three 250 cfm carbs on a 331. Throttle response and mileage are far better than with a single four. Plus it just plain looks cool. That said, no matter what size carb you put on an engine, it's only going to flow what the engine will pull thru it. A smaller sized carb works better in most cases. That's why the 3x2 works better all around. You're running on the center carb at all times with the outer two as secondaries when you wnat them.