[blykins]

Is it a flat tappet camshaft? That's the first question I would have and even if it's been run in on a stand, I'd still take it easy for a bit.

On the dyno, this is how we break them in.

Fire them up, set the carb and the timing. Put a very light load on them and run them for about 30 minutes. After that, I put a short pull on them to about 5000. Then I run the valves, do an inspection, etc. Then it's on like Donkey Kong.

In the car, you will want to follow pretty much the same procedure. I would drive it a lot on an open road, getting up to speed, then letting the engine brake the car back down to a lower speed. Let it climb back up and do it again. Keep an eye on the gauges and remember that when engines heat up, valve lash/lifter preload changes, so keep your ears open too.