[Nickv]

That rpm seems high going thru the traps. What rear gears are you using? My 67 goes thru the traps at 5500rpm, turns 12.6, that's with a 3.73 rear. My engine is a 455+.030 over with trw pistons, and SD rods, 4 bolt mains with studs. Same engine since 1991 and before I bought it, it was a drag only car with the same shortblock.

What are your clearences on the bearings? Are you using studs for the mains? What is your oil pressure at idle?, at speed? Mine at idle is 25lbs, cruising 60lbs, and when drag racing 80lbs.

I'm no expert, but it seems to me that your bearing clearances may be to loose, or your just spinning it to high. 455's don't need much rpm to get them moving down the track.