max compression on pump gas\steel cylinder head\241 @ 50 cam

I checked my cranking pressure a while ago and it was 148 psi.
I did not pull all the plugs and the engine was kind of on the cool side.
I will warm her up good and pull all the plugs and then check it.
I am changing the plugs soon so it will be a good time to check.
I am going to check my piston to valve clearance and see what my choices are.
If i advanced my cam and cut the heads it would most likely help.

Has anybody advanced the cam in their engine and what was it worth in ET??
ive advanced it a 2 different 318s,it shifted the rpm range about 500 rpms lower,cranking compression came up some,it was more responsive,but the idle got a little rougher it seemed.couldnt tell you an actual "et gain"it just felt like it picked up low end.