help 451 loosing coolant somehow.

check the plugs, at least one of them will look different if its getting in the combustion chamber.

I had a similar problem. Coolant would dissapear. Cooling system held 15 psi overnight.

Had a hairline crack in a cylinder wall, when hit it would seep into the cylinder and go out the pipe as steam. Finally found it when the leak filled the chamber and hydrolocked on the next start up.

Odd thing was that somehow the water was pushed into the intake from hole 3, and hydrolocked #6. Found the crack on engine tear down.

This can be maddening! A shop I worked at had a Camaro with a small block loosing coolant. Engine ran well enough, but lost coolant. Shop owner replaced the short block, had the valves ground and heads surfaced, still leaked. Finally found a crack inside a port. This was back when Chev small block heads were cast 3# lighter in Mexico. Blame the engineering not the foundry. Machine shop shared the cost, but no one won. Pressure test the assembled engine and then the heads and you will find it!

Thanks for the info guy's keep it coming if anyone has run into this issue. This is my friends engine. The short block was bought from a very well known big block stroker engine builder. My friend is sick he has many $ in the engine and virtually no use of the engine so far. We will try the pressure check but I'm afraid it my be in the block. The moisture is in 2 cylinders I think but can't remember which #'s. I think he's going to join here so he can post questions.

I have seen coolant loss from exhaust studs running down the headers and into the exhaust system. The owner put head gaskets on it and still had the issue that's when he called me.
Gus

This engine is a very mild build with iron heads in a 63 Plymouth street cruiser. The builder is not in P.A. I do not want to bash them til we see how they handle the situation. I will say my friend had issues from the beginning with this engine including a rear main that leaked badly. My friend spoke to them at the nats about the coolant issue before we pulled the heads again.We had them checked again and local shop says they are fine they pressure tested them twice magnafluxed etc. The engine builder did not seam like they were very open to making it right if it was the block. I hope they will. I feel bad as I suggested this builder to him, as they supposedly really know stroker Chrysler bigblocks.

what is there to know? unless he ground a custom cam and hand made a main girdle everything else is off the shelf and tried, tested and verified in various books and magazines.

it is not my intent to be a jerk, there are just many bozo's out there claiming to be the guru of something.

i hope, for your friends sake its something simple so he is not out the cash and can get his car back on the road.