I waited a long time for my 496 build only to have it fail. It is a 496 with 13-1 compression. Rotating assembly was new except for crank. It was std on mains .010 on rods.New ud harold/lunati solid roller with new comp lifters.Heads fresh from machine shop.After bringing it home clean,i rewashed everything myself to be absolutely sure.When i cranked it,it had 60 lbs oil pressure idling 25 when hot.Thats exactly what the old 454 was with no problem for several years. I ran it some in the shop and drove it a few miles. Every thing seemed ok.Took it to the track,done my burn out,staged and left the line and my shift light never came on. Looked at my tach-5800 and not moving then to my oil pressure 10. Loaded up ,came home,tore engine down.It had a spun rod bearing,all the other crank bearings just fell out of the block with no tension.Three spun cam bearings and a ruined 400 dollar cam.Lobes are perfect as are the lifters.Plenty of oil up top.One very peculiar sight is the combustion chambers and exhaust ports which were polished when assembled.They are so rough and it feels so gritty almost like pool sand.Tops of pistons same way.No damage to any of this ,it just scrapes off with fingernail.Can anybody help diagnose these multiple problems?I got one good thing out of this and that was the feel of the holeshot with the left front wheel up 8 inches,but it wasnt worth what i spent!