i bought a used motor from my friend that runs perfectly. Its a d15b8, and i took the head off of my d15b7 (which i blew a rod through the block). Would blowing the motor mess up the head? Because i swapped the heads so i could have 16 valves rather than 8. The timing was fine when i put it all back together. When it started up, it was puttering like the timing was still off. Or would the ecu mess up since its supposed to read 8 valves instead of 16?? Any help????

 

The head should be fine. You need the ECU that goes to the D15B7 though. The code for the ECU is P06. You need one that corresponds with what transmission you have. manual and automatic ECUs are different.

Also, did you check the ignition timing also with a timing light? The igntion timing might need to be adjusted by turning the distributor either way until the mark in the center of the group of 3 notches on the pulley are aligned with the timing light mark on the timing belt cover whenever the engine is at TDC (when cylinder 1 fires - the cylinder closest to the cam gear).

Also, Is it possible your crank pulley and cam gear are out of sync by a tooth?