I agree with most of the replies. I just did a break in on my newly rebuilt 389 with Tri Powers in my 65. Upon start up I had oil coming out of the breather in my original style unbaffled valve covers. It appeared that the fan does a great job spreading the oil mist all over the engine bay. No harm done and was a messy although relatively easy clean up. At about 100-150 miles the engine started to settle down, rings were starting to seat and the misting disappeared. If the engine was rebuilt properly, decent break in, the more miles you put on the happier the engine is; oil, plug and temperature wise. I am not sure I would get on the Tri Powers until you get a few more miles on and you get the rings seated. Solve one problem at a time. Just my 2 cents.