A question on carb sizing

[Ghoste]

It seems that Mopar engines typically will take a little more cfm in carb size than what is recommended by carb suppliers.  Now I am only supposing here, but my guess would be that this is because most of these size guides are generalizations printed with Chevy's in mind since that would be the bulk of their business.  So why is that Chryslers seem to respond better to e little more carb than one would expect?

[firefighter3931]

It really depends on the carb and application but i see a lot of overcarbed Mopars on here and other websites. I prefer to go a little conservative and have strong throttle resonse...especially in street builds where drivability is a concern. Velocity is as important as max cfm unless it's a race build. 


Ron

[Ghoste]

But if you go by the accepted formula, even a 440 shouldn't want anything bigger than a 700?

[firefighter3931]

But if you go by the accepted formula, even a 440 shouldn't want anything bigger than a 700?

Yep, that's what the formula says. Of course it depends on several factors which include the cam profile/cylinder head flow and intake manifold style (dual plane vs single plane). 

Mine pulled just under 800cfm at WOT on the dyno with 300 cfm ported E-heads and a .580 lift solid cam.....the Proform 750 dp'er made more HP than a Holley 850 dp'er in back to back testing...go figure. 



Ron

[Ghoste]

Which of course is entering into the volumteric efficiency part of the equation, but it still seems to me like a  Mopar will want more carb than a similar size and setup Chevy.  This, in conjunction with the reportedly poorer flowing Mopar heads.  Am I just noticing it wrong or this really the case?