I know this is a tech question but I don't seem to be getting a lot of input, help? I've got about 3500 miles on my rebuild of my 1975 350. Turbo 400 trans with a mild shift kit. At end of build engine dyno'd at 309 with 360 torque at 4650 RPM at flywheel. Since the dyno I installed shorty headers, true duel exhaust with crossover, Performer intake, 650 cfm edelbrock carb. I was happy with the power but just wanted a little bit more so I put a set of Brodix IK180 alum. heads on. The heads are 70cc with 180 cc intake. I noticed no improvement in power, and was told to expect about 50 more ponies. The cam that is in is a Crower 241
Intake: Duration 270 deg Lift 456
Exhaust: Duration 276 deg Lift 458

I talked to a few people that think I am undercammed and that the heads will work better with the correct cam. So I talked to Comp cams and they suggested a Xtreme energy Hyd cam #12-246-3.
Specs:Intake duration 274
Exhaust duration 286
I'm not a cam guy but the spec sheet doesn't give any other lift.
Will this cam produce more low end power? Will it give my motor a nice sounding lope, and will I have to change stall. I just don't feel the combination I have isn't to the limit it should be and as far as sound, there is no lope to the engine. This car is driven several days a week. Thanks in advance guys, you've always been right on the money in the past.

 

There can be a few reasons why your not getting the power you think you should. One can be compression. I am assuming flat top pistons,which would give you in the ballpark of 9:1. Another big reason could be in the timing and timing curve of your dist. The cam Im not familiar with. I would have to look it up. Comp cams should have a stall convertor recomendation for it. If your car doesnt have a higher than stock stall or a decent set of gears in rear that can also hinder performance. The HP curve of the motor and the rear gears should be dialed in together somewhat. The comp cams energy series give good lumpy idle. hope this helps.

 

http://www.summitracing.com/parts/CCA-12-246-3/

 

Comp Cam has a program that you can download on to your computer that helps you select a cam based on your cars weight, drive train and engine and engine upgrades. It’s pretty cool to play around with. The program is available on their website free.