240sx354

Hey, i just bought an S14 SR the motor was sitting for a while and when the kid took the head off to do a metal head gasket he gave up on the project, he had the head pressure tested and it had like 45% loss in the middle two cylinders. he said it was just because it was dirty...since those were the valves that sat open... i took some of them out and cleaned them off, they were pretty dirty but when i put them back in i took a flashlight and shined it on the bottom of the valve and i could see light coming through...i dont really know what to do seein as how this is my first SR... if you need any more info to help me out let me know..