how does it run on the stock setup? I just do a mild build man, piston, rods and headgasket..

 

You might try a quick retorque of the head and of course check the spark plugs because if they are wet then you know which cylinders are leaking. You could also have a leak along the intake manifold if there are coolent connections there. Another thing to check is pressure in the radiator when you start it up - cylinder leaks make radiator pressure jump right up - exhost head leaks not so much pressure.