cant smoke the skins...problem??

ok.
I have been going nutso over a "problem"? or a severe mismatch.

the basic problem is....I cannot smoke the rear tires off....heck I barely get scratch, powerbraking is no problem, but just from a take off it wont do it.
It seems slightly doggie off the line, but comes in real quick and pulls like crazy clear through 120 mph....havent taken her past that yet.

So I am thinking I have a combo problem....any one with better knowledge than I willing to help me??

Here is the layout.
1974 360 bore .060, 9:1 pistons, polished steel crank, double roller timing set,
MP cam .284/.484 108 degree. stock rockers, hyd. lifters.
cylinder heads are cast irons, tweaked out, 1.60/2.02 3 angle valve etc...
Edelbrock rpm intake, Holley Street avenger 780 carb. MP distributior and chrome box ignition. 8mm wires.
stock exhaust manifolds currently (a killer) 2 1/2 tubes to 40 flowmasters
727 load flight trans, 3000 stall convertor. B&M mega shifter.
8 3/4 rear with a posi 3:91 grinder set

I am personally thinking the cam is wrong for a quick launch. It seems to like the high rpms.

the beast was supposed to be a hot rod type cruiser with some punch, not really a racer. I was hoping for at least 380 HP. I havnt dyno it yet, but feel were getting closer to that mark. I am thinking of running a Comp energy cam, and changing intake to a air gap or torker. I am holding out on the exahust to find some 340 HP manifolds...yea..right..

anyone have a better idea on a cam selection? or any ideas one what to check out for my concern???

all thoughts appreciated.
-RPM