plymouthrr1985

Hey guys i have a street built 383 and have been looking for a good carb. The specs on the motor are 10.5 to 1 compression, lunati 60302 cam, ported edelbrock heads and intake and will be running tri 1 7/8 headers. Been lookin and a 770 street avenger or edelbrock thunder avs 800 or are these too big?

Mr.4spd

Transmission? Rear gear? If it's a stick car with 3.55:1 or steeper gears I'd drop a Holley 750 double pumper on it and never look back. Auto and/or highway gears, 750 Holley vac secondary.

plymouthrr1985

727, 3.23 gears for right now, planning on switching to 3.55s

Mr.4spd

I looked up your cam specs, pretty serious for a 383, you're not running the stock converter I presume. I'm still thinking Holley 750 DP, it fits the theme I think you're going for which is a snotty fire breathing 383. You can always modulate the throttle input, but I doubt you'll have to.

Archer

Plymouth -

Agree with 4spd on the 750 DP, but here's something you can play with... (just be honest with your input)

http://www.holley.com/applications/C...bSelection.asp

Archer

rickyr

I would go with the 770 Street Avenger With the auto trans.
The Avengers are dry flowed and @ a true wet flow the 770 is about 750 cfm that is still a bit big but being a vacuum sec. it will only open as the engine demands.
It also has a life time warranty

Mr.4spd

That carb selector is awesome, Archer. I think it's more guidelines, though. I ran it for my application and I'm supposed to be using a 1050 cfm vacuum secondary. Hilarious. I use an 830 cfm DP and you'd swear it's fuel injected.

rickyr

I would not go by that selector, it is fun to play with, but not that acturate
do cubic. inch X max RPM diveded by 3456 = CFM
And then if it is a light car and a stick and low gear go dbl pump.
other wise go vacuum sec.