[QUOTE=Tumarr]For a 406 cid small block, Normally aspirated, 600 hp with that cam is a very tall order for that motor. I'll bet that if you get that engine to a chassis dyno you will be seeing ballpark of 380 to 400 hp to the wheels. now this is about 20% less than what you fly wheel out put is. Do you know the stroke they used and bore size they used to achive 406 cid? I remember you saying that they used you original block which is a 350. that block has a 4.00 bore stock. the typical 406 uses a 400 block with a 4.125 bore using 5.7 rods rather than the 5.56 rod the stocker came with. that and .030 bore out. Are you sure they didnt build you a 383?[/QUOTE]

apparently I was confused...he was gonna re-use the block if he built the 383, but when I decided on the 406...he used a chevy 400 block he had, and kept my 350 block as a core charge.  no idea what stroke and bore, I'd have to ask him on Tuesday.

If that is a new engine build and its leaking oil and smoking like that then I would question how good the builder is and who you are spending money with and what type of bull they are feeding you.

Your front and rear seals should not be leaking if new.  Its critical to put a dot of sealer at the corners of the pan gasket at the front and rear mains to ensure they don't leak.  Sounds like your guy forgot to do this.

I also forgot to tell you on the rear you should spread a small amount of sealer onto the main surface over ontot the rear main seal where the upper and lower halves join or you will have a leak.