Most of the blocks commonly available are 70's truck. Nothing wrong with these. They are two bolt blocks that are fine for a street car. If in doubt install main studs instead of bolts and you will be ready for serious horsie power.

The cast crank will take all a serious street runner can give it.

Use a good piston, K B makes a piston with short dome, shoot for 9.5 compression. Big block chevies do like to break rod bolts, so replace them with good ARP types and resize them. The good 3/8 bolt rods will take a lot of H power and street rpm. I've used them in an old econodigger that saw lots of rpm.

The desireable street heads are the early seventies oval ports. The rectagle port heads are somewhat rare on a rebuilder type motor and are not needed for a streetable car. Most of the desireable casting numbers need hard exh. seats installed for reliability and most hot street engines opt for the 1.88 stainless exhaust with the 2.19 intake valve. USE GOOD SPRINGS! As big blocks have been known to drop valves. This is due to the large intake valves, guide wear and not enuff spring.

Big blocks like split pattern camshafts and the more lift the better. Keep the effective duration down below something like 230 deg. A good 4bbl aftermkt intake and a 700+ cfm carb. An aftermkt distrib and headers will make a potent street runner.

REmember to flip your heater core and redrill the box. Otherwise you will have broken heater tubes all the time. Use a BIG radiator. and power disc brakes. That stock rear won't last with good bite'n tires either.

BEEN THERE MANNNY TIMES!!