[bigjohn.94]

OK, I got one for you engine tech guys. I am building a 72 monte carlo with a 454 and th 400, I am running stock compression and heads, a weiand single plane intake, edelbrock 600 carb, long tube headers, and holley electric fuel pump. it pushes a 10 bolt posi rear end with 4:10 gears. My question is, what size cam should I be running? Could I change to a good size cam without changing my stall converter?

[66GMC]

First off ... that 600 cfm carb is much too small for your setup. There's not much sense in replacing the cam if the carb can't supply the air/fuel. You have to match all of the parts to operate within the RPM range and intended purpose of the vehicle.

I'm going to assume that those heads were original to the 72 Monte, and they are not "peanut-port" truck heads.

Pull the valve cover off, get the casting number, and then head over to nastyz28.com to decode it to see what you have.

There have been about a bazillion threads regarding BBC camshaft selection. A "lot of cam" will require a fairly high compression ratio and a stall coverter.
If the car has vacuum-booster power brakes, you may have to either supplement the vacuum or convert to hydroboost.

Use the "search" feature. LOTS to study up on.

[bigjohn.94]

Actually the motor is from a truck and has the round port heads, and I do have an old double pumper holley I could throw on, I've just never had luck with holleys and electric fuel pumps

[454C10]

you have the right gears but need more compression and stall for a big cam.

you can run a bigger cam than stock, but not that much bigger.

get a cam similar to a 260H compcam with stock cr (7.5:1 cr).

[66GMC]

Originally Posted by bigjohn.94

Actually the motor is from a truck and has the round port heads, and I do have an old double pumper holley I could throw on, I've just never had luck with holleys and electric fuel pumps

Yeah, those "peanut-port" truck heads are surely going to limit your capabilities. They're designed for relatively low RPM, "stump-puller" duty.

I'd recommend a fuel pressure regulator for use with virtually any performance electric fuel pump. You'll want to keep the pressure down to about 5 PSI. It's fuel volume that you're looking for on a BBC, not pressure.

If you're going to use a double-pumper on an automatic, you'll definitely want a higher-than-stock stall convertor. I'd imagine a 2500 - 3000 RPM would be OK on that. A '72 Monte is not a real lightweight, but you do have the gearing in your favor.

Should be a fun ride!