350 SBC Carb Size questions
 

I have a mild SBC, Vortec heads, Comp 264HR Cam, performer EPS intake, with the DUI ignition. The carb I have is a older (1990ish) holley 715cfm with vacuum secondaries. When I pulled the bowls off the carb they were full of rust. I was able to get them clean enough to get the thing running but am wondering if I"m better off with a new carb in the 600CFM range. Currently I'm having an inconsistent idle with the 715. I can buy new bowls etc but don't want to waste money on something that could be new and a better size for the engine. One recommendation from a previous from was the Edelbrock 1409 600CFM. Another was the Quickfuel 600CFM. I'm looking for easy and reliable. And I'd like to get something that will work well out of the box without a ton of tuning. Thanks for the help!

Ive had great luck with the Holley marine carbs right out of the box.
Ran a 650 on a vortec 383 SBC that had an XM262 cam. Idled excellent, ran great.

Run a brand new marine Holley 750 on a mild 454, also runs excellent. All I did was remove it from the box, put it on and adjust the idle screw.

I'm sure I'll get some disagreement on this, but I would run a Q-jet if your manifold has the bolt pattern for it. Ran one on my 454 for years, bulletproof and troublefree, and particularly on a 350, I really don't think you will see a performance gain from a Holley over a Q-jet. They are cheap and plentiful, and one from a 350 Mag should work fine on your application, even with the mild modifications.

^^^^ Agree. People bash the Q-jet all the time, but they are prob one of the most trouble free carbs out there.


John jr

I ran a Q-Jet on my built 355s. The Carburetor Shop in Ontario California helped me with jets and rods. They gave me their recommendations and said there might be a bit to gain going to one side or the other of their recommendation. I bought a ton of parts and got 50 r.p.m.s going one slight step richer than their original recommendation. I'd recommend going with their stock recommendation if you go Q-Jet.