rebuilding a 273 180 HP engine

probly the best bang for the buck in this situation is to pull the engine and do this...

fix whatever is leaking with a total gasket set (felpro-$70)
new oil pump and timing chain ($50-for stock replacements)
stock off the shelf 340 cam and hyd. lifters (seen them as cheap as $80 new)
junkyard late-model #302 heads, rocker assemblies, and pushrods (no more than $100)
performer intake with a small 4-barrel (swapmeets and craigslist...anywhere from $50-$250 for the pair)
general electronic ignition goodies (once again stock stuff...$100)

it fixes the leaks, the smokes, the miss that is most likely there, retains a 'regular' gas compression ratio, increases drivability, decreases maintainence, and will add somewhere in the area of 35-40 horsepower