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71nFun 03-12-2021 10:10 AM

carburetor size question?
 
ok folks... engine is SBC350 bored .040 with sportman 2 heads 2.02 valves. edlebrock performer intake. cam is semi mild with .490 lift. 112 lobe sep. MSD 6AL ignition. question is whats a good size carb to go with?

geezer#99 03-12-2021 10:40 AM

Re: carburetor size question?
 
Your engine Specs are about like a sb I built but I used twisted wedge heads.
I used a Holley 3310 750 vac sec.

71nFun 03-12-2021 11:23 AM

Re: carburetor size question?
 
Thank you. was thinking 750 but didnt want to have too much carb. heads seems like a decent flowing head but cam isnt very stout. Thanks for the tip!

PGSigns 03-12-2021 06:27 PM

Re: carburetor size question?
 
I have a Holley 670 street avenger on my 66 with a L31 crate engine about the same cam and a super victor. Runs really good.
Jimmy

garyd1961 03-13-2021 06:14 PM

Re: carburetor size question?
 
I just happen to have a new 770 street avenger when I installed my L31 so I used it. I did reject the primaries down a couple sizes but it runs good. I always heard you can get away with an oversized carb if it's vacuum secondaries.

Captainfab 03-16-2021 09:58 PM

Re: carburetor size question?
 
A 600 cfm carb is sufficient for a 357 cu in engine if you aren't turning it much over 5000 rpm.

mattfranklin 03-17-2021 06:46 PM

Re: carburetor size question?
 
Holley 770 Truck Avenger on top of a 1970 stock cloned LT-1 350 (reasonably close to stock Corvette LT-1/Z-28 specs for 1970), 0.030 over.

As GM designed it, their LT-1 came originally with a 780 Holley 4150 (of the 3310 family), so that's why I picked something similar for my clone.

Runs and idles great once tuned.

Tom 03-19-2021 08:22 PM

Re: carburetor size question?
 
Its a 350 with a small intake, no idea on cam but a hydro flat tappet with .490 lift is usually around 230@.050 so medium cam, and decent but not great heads. I'd put a 600 on it. 750 will work fine too but more then needed.

Captainfab 03-19-2021 09:49 PM

Re: carburetor size question?
 
Here is an online calculator on Holley's website.

https://www.holley.com/products/fuel...s/carburetors/


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