Rep Power: 0

I running a 97 honda civic with a d16y7 motor. I recently did a bottom end rebuild with h beam rods and ycp vitara low compression pistons for boost later down the road. The engine is NA right now for the break in period just to be safe, but when i did a compression test each cylinder only had about 75 psi. I wanted to lower the compression but definitely not by that much. I had a mechanic buddy come look at it, and he said that it could be a maladjustment in the valve train, or the pistons themselves. Im gonna double check my valve train today but if anyone has any other ideas it would be appreciated. I can use all the help i can get.

 
Rep Power: 518

Cam timing needs to be on the money. A tooth out of time hurts a bunch.

Valve clearances all adjusted to spec? Tight valves cause compression drop

Lack of oil? Rings need oil to seal. Did you oil the rings and coat the cylinder walls before shoving the pistons in?
Flooded? Raw gas can wash the oil film away from the rings and walls, then compression goes away....plus wet plugs won't fire

cranking speed? fully charged up battery and good starter?

old fuel?

plug wires/firing order/spark