I'd run it for an hour or 2 varying rpm and shut down and sit after every 30 min or so and cool down. I didn't see what kind of motor you were running but I assume it's rebuilt stock. If so I'd run rotella 15-40 it has the highest zinc content for flat tappet cams.

At 2 hours it's had quite a bit of break in time. Don't baby it. Put some load on it to set the rings, vary the rpms. Change the oil soon. Idling a new motor isn't helping it, drive that thing.

thanks! i have yet to have it out or even start it since i got it. the weather here has turned to crap the day i got it. sleeved stock bore, comp 11-244-4 cam, comp roller rockers, edelbrock victor intake, holly 850 CFM carb. everything else from the rebuild sheet was pretty much stock matched.