I have a D15B7 in my 89 Hatch. I am running PM6 with the DX harness converted to Si. I have a Y8 head and ECU on the way. I didn't get the Y8 intake, so I didn't get the wiring harness either... So would it be easier to convert my harness again (cut every single wire going into the ECU, and splice them with the correct wires on the P28) or will a Y8 harness work on the B7? Bottom line, I don't have enough money to get a Y8 intake mani....

 

The easiest thing to do, would be just use your PM6 ecu, distributor, intake manifold and use all your current wiring. Basically just swap heads, leaving everything else intact.
Then all you would need is some way to activate vtec.
You can have your PM6 chipped with vtec fuel and timing values.

Thats the easiest/cheapest way. Not neccesarily the best way.

 

The PM6 (or any obd-0 ECU for that matter) isn't going to run the best on the Y8 head... The PM6 is going to run rich before vtec, and mostly lean during vtec. I highly recommend a VAFC combined with the PM6 if you plan to use the Y8 head and stick w/OBD-0... If you were to use a Z6 head, then I'd recommend switching to OBD-1, and use the P28 computer. Don't waste your time trying to convert to OBD-2, I'm sure it can be done, but it's not worth it. WAY too much work/modification involved in doing so - you'd have to lose pretty much ALL of your exhisting wiring, and replace it with OBD-2 wiring. Then you'd have to get some extra parts/sensors as well.

 

Thats what I figured, but I don't have the money for a VAFC either... I read somewhere that 88 and 89 PM6's weren't chippable... Is that true, or can they be chipped? I know I can just stay with my PM6 and run VTEC with a switch or RPM switch and all that, but I want to get the full benefits of it. I guess that requires money. Crap.