scat 400 crank, JE pistons, CC306 cam.

last night it ran fine, i pulled in at home, and this morning it ticks like there's a problem in the valvetrain and feels like there's only 7 cylinders running. another thing i noticed is that oil pressure is not going up/ down with rpm anymore.... someone give me a few simple things to check before it's off to the speed shop to get the heads pulled

 

got a Code 33 on freescan about the MAP sensor.

 

vacuum is almost non existant at idle, but i get about 30 kPa at 1,500 rpm...