okay so I have a complete d16z6 engine and I want to put it in my 91 civic with a d15b1 currently in it. Can I use the z6 harness with the p28 ecu or do I need to convert to mpfi and obd1 first?

 

You should not use the Z6 harness.
It will not plug to the firewall connectors.

You should do the DPFI > MPFI
and OBD0 > OBD1

 

Will my b1 harness work with the z6 and also how should I wire vtec?

 

GOOGLE

DPFI to MPFI
- about 12 steps that you need to do to the existing B1 harness at the ECU as well as under the hood.
OBD0 to OBD1
- a jumper harness that you buy that allows you to plug in the P28 ECU to your existing harness. Decent jumper harnesses include all the information you need for hooking up vtec.

 

Okay thank you very much. I tried using google but for some reason I couldn't figure it out. But it seems fairly straight forward now.