Hey guys i need some help. i bought my 90 ef a couple weeks back and it didn't run. Np, so i took the motor out and found out that the motor is a D15B7. Again no big deal, the head was bad so i bought a new one. The problem I'm running into is the old head code is a PM3-13, which to my knowledge is a D16A6 head. The head that i bought is for a D15. Will this head work or do i have to by another head for the car. As far as i know, to run a D16 head, you had to do a couple other things to the car. Any help is greatly appreciated guys.