I'm very happy with my "55 331, but will relate the story of its history told to me by the seller who said he was retiring and moving to Phoenix from here in Washington some 20 years ago now. It, he said was completely rebuilt by a GM certified mechanic working for a Chevrolet dealership in Tacoma. A hand full of receipts came with it and the mechanics phone #. (the price also included a 727 Torqueflite). I called the mechanic, he assured me it was a good build, had been in a 37 chev with maybe 1 K miles and was a good perfect rebuild. Well it sat in my garage for a few years before my frame was complete and ready for it. I cleaned it up, painted it twice, (different color), dropped in the frame, installed a modern electronic Hot Heads distributor, changed oil/filter, hook up temp and oil pressure gauges, change plugs, new HH wires, install radiator. Big day comes, neighbor and I turn it over, it fires right up. Sounds great, doesn't overheat, has 50lbs pressure on start up, dropping to 30/35 on warm up at idle. Let it run 30 minuets or so, starting it off and on. Pretty damned happy. Oh also run the the gears checking out both tyranny and Jag rear end. Aw but wait!!!!!!........... Start noticing blow by, not a lot but enough to be noticeable. OP is still where it was on start up. Third day after start up she blows while giving it a work out. Tear down reviles the nut on the cam was not installed correctly and had loosed, spun off and was laying in the cover, mixing up valves and pistons. GM certified mechanic my ass!!! Damage existed of some bent push rods, a small mark on #6 piston. I take that head down, have it repaired, button her back up. Say to myself, "I'll get to the blow by after its on the road". Guy I bought it from is long gone, can't go back on him so I chalk to another live experience, and call it good. BTW blow by is still there, might fix it, and at 81 y.o., might leave it for the next guy. I guess I shouldn't bitch to much, out the door, with tyranny, he sold it to me for $2500.00, but that was in the fall of 2000 also. Sure wish you all the best with your HEMI, there is nothing like having one, and hearing that unique exhaust sound they make.