Compression readings

the readings seem awful high for a stock 383, should be closer to 150- 160.
what heads do you have ? closed chamber or open chamber.
Exactly what im thinking......All I know is the original head was off a 290 HP engine.... What head the rebuilder used to replace the cracked one, I dont know
Tomorrow I take off valve covers
My only thoughts are was this head milled and the rebuilder never picked that up.
The other head would be more in line with a stock 383