newbee here need oil help

My son & I picked a barn find 73 340 duster. the car was built for the strip & speed back in it's time, example 489 rear end with 488 gear's (changed to 323) 7msd box 8000 chip with strip only coil high rise manifold 750 holly, reverse valve trans. plus much more first thing we did was to get it started when we got it home it ran great so we changed the oil to 10w 30 since then we have had the car redone not much to do but the cosmetic's body paint ect have not driven it much but the odd drive down the road just to hear it run & see how much power it had holy **** it goes .now to my ? I'm not a motor guy I read a thread that mentioned zink level's in oil now that the car is ready to drive what oil should I be running in this high performance motor. please don't ask for spec's on motor I really don't know at this time but from what else I see on this car it was built for speed I would hate to destroy it till I know thank's