Quote:
Originally Posted by jmking9
I'm about to put a new carb on my truck and am looking for a little advice from the Holley experts (because I'm FAR from one of those) After a lot of reading and talking to a couple different guys that have experience with Holleys, I've got conflicting info. Would a mechanical, or vacuum secondary carb be best for me? I went into this thinking I wanted a 650 DP. But after doing some reading, I'm wondering if the 670 Ultra Street Avenger would be a better choice for a street driven truck. I wanted to hear some opinions or advice on either one of these or even something else that would work better. I'm open to suggestions. Here is a few of the specs on the engine/truck
*355 ci with 9:1 compression
*Edelbrock RPM aluminum heads
*RPM air gap intake
*Comp XE 268 cam
*Auto trans with 2000-2200 stall
*3.73 gears
*5000 max RPM
*Currently running a 600 Edelbrock that performs "ok" I'm putting this carb on my jeep and hoping to find something that performs, and looks a little better for the truck. I'm really wanting to give a Holley a shot.
What are your opinions on a carb for this setup?
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Your engine is just a very complicated air pump. To figure out which carb will work best use the following formula :Carb Flow rating in CFM= DISPLACEMENT (cubic inches) x RPM / 3456
So, for your 355 cu in motor, (355x5500)/3456=566 CFM. So a 600 CFM carb would give adequate performance but a 670 is the largest you should run. And, before all you magpies start chattering about density altitude, volumetric efficiency and all the rest of that stuff only racers care about (like elevated compression ratios);the formula is for a stocker that is just a daily driver all of that boy racer stuff dissipates like a fart in the wind and leaves no lasting impact.