JaQuan Holley

So I have a 305 in my Camaro RS, with a MSD ignition box, long tube headers, and a few other changes. The guy that sold me the car said it has a comp cam 511. Ever shop I take it to says the cam is to big for my motor, that's why my take off is ****ty. Instead of me putting in a smaller cam, what can I do to make my motor handle this one?

JakeRobb

When a cam is "too big", what that really means is that it is designed for more airflow than the engine can actually produce. So, to increase the amount of airflow, you have a few options. The first and easiest are an air intake and exhaust. You already have longtube headers, so I'm going to assume you have good flow in and out. That leaves internal engine changes. You could port the heads, install higher-ratio rockers, or swap the heads out for even higher-flow versions. You could increase the engine's bore and/or stroke.

Unfortunately, almost all of those options are more expensive and/or more difficult than a cam swap. I don't know anything about the 511, so I don't know by how much it's too big. Without that information, I can't predict what would or wouldn't actually help in your specific scenario.

In your shoes, I'd seriously look into selecting a more appropriate cam.

There is another possibility. You said the problem is that your take off is ****ty, which leads me to believe that performance is okay once the revs are up? If so, another thing you could try is a high-stall torque converter (I'm assuming your car has an automatic transmission). That would let you launch with a higher RPM, and it's a popular mod among auto guys.

Injuneer

Signed off 4 weeks ago immediately after first post, and never signed in again.

JaQuan Holley

It's an automatic, an yes, it did fairly nice after I got my speed up. But unfortunately my crank broke. So I bought a 350, gonna swap over my parts to it soon.

How hard is that to do?

Injuneer

Comp Cams listing shows 12-511-5 as a solid flat tappet cam, 242 Intake/250 Exhaust @ 0.050", 106-deg LSA, 0.51/0.53 lift. Shows intended use as "1/4 to 3/8 (mile) high banked track in a heavy car with limited intake and carb". Huge overlap, intended to make HP at high RPM (6,200) on a track. Would expect it to be extremely weak on torque at low RPM. Definitely not a street friendly cam in a 305ci engine. Needs 3.73 or 4.10 gears and at least a 3,800 stall. Won't be much better in a 350, without gears and stall.

JaQuan Holley

Okay, thanks. So, how much is a stall? An how much work is it? Can you link me to the parts necessary to make this cam work in my 350?