Flat top pistons and 64 cc heads might give a little too much compression for street use. Under 64 cc heads, you will yield 10:1 compression with the piston set .015" below the deck and with a .039 head gasket. With 67 cc heads, you're looking at a 9.7:1 compression ratio. With 72 cc heads, you're looking at 9.21:1 which will run on whatever gas you put in there. World makes a head with 170cc runners and 67 cc chambers. It doesn't take much to make 350 hp and the 170cc runners of these heads would be excellent for the street. The combustion chamber looks a little dated, though. Dart makes a head with 72 cc chambers and 180 cc intake runners. It uses a much more modern combustion chamber which looks similar to the Vortec. The world heads will cost $800 for the pair and the dart heads will run you $1000. AFR makes the best street heads, but they will cost you at least $1200 for a pair. All of these heads will work with standard manifolds. For the cam, Comp's XE256H and dart's S/R heads made 330hp according to their dyno on 9.25:1 compressoion. I've seen numbers as high as 400 hp with different combinations of intakes, carbs, and heads and that cam. I am personally running that cam on 9.25:1 with Vortec heads and a dual plane manifold. It does make that power and it does make an excellent street cam. It makes more torque than a stock cam at every rpm, even off idle. It makes over 400 ft lbs of torque by 3000 rpm which is really useful when passing on the highway. It has no problem getting my truck rolling with 3.07 gears in the rear and a stock torque converter. For a litlte more performance, Comp's XE262H is the biggest cam they recommend for use with the stock torque converter. It still makes good vacuum and will idle, but it wont be perfectly smooth.