Most chevy small block engine aftermarket manuals will give very detailed specs on the engine and it's difference's from the other "small blocks" as well as similarities. The specd out motor that a buddy ran on his desk top dyno for my own 400 conversion in my 86 3/4 ton. 400 block bored .030 over (406 cubic inch), with flat top pistons ( not factory dish), World Products sportsman heads w-2.02/1.60 valves and 76cc chambers (approx 9.0-1), Or if cost is a factor go with World Prod. S.R. torquer heads w-2.02/1.60 valves and 76cc chambers these don't flow as well as the sportsman heads.I also like Total Seal gapless rings, and also upgrade to the 350's 5.7 connecting rods instead of the short 400 rods (since you have to buy pistons any way with the over bore). Depending in several other things a cam shaft with a .442 lift to a .480 lift, but check with a cam manufacturer for further details on your specific needs, remember bigger is not always better. As for an intake I like the Edelbrock performer intake. There are others that are probably better but this is the best all around intake i have found for HP and Torque. You can go to the Performer rpm but you give up alot of torque because it raises the power band in the motor and increases the HP in the upper rpm levels but not down low for grunt and torque. Also use a good set of headers and good flowing efficient dual type exhaust. This on the desk top dyno gave 404 to 421 hp with some different stuff in the motor and other variables. This is the way my 400 will be built after i finish the new motor for my stock car. I don't what the margine of error is on a desk top dyno, but this is a good stout running motor. If you want more of a Horse Power motor for a hot rod truck change the cam and intake and some valve train parts and you'll be ready to go. TMW