Hey guys i bought a 91 hatch dx with a d16a6 head on a d15b7 block recently..

The wiring is all hacked up and missing clips and the wires to where my a/f sensor , fan switch and o2 arent hooked up. When it ran it was super rich.

It doesnt have the dpfi>mpfi swap and wrong ecu in it.

I need to know which wiring harness, ecu and what all is needed for the mpfi swap and which is best for this build.

Some help getting this thing pieced together the easiest and best way possible would greatly be appreciated!

 

Since you have a D16A6 head, it gets less complicated.
You will need a D16A6 ECU, D16A6 distributor, and a complete MPFI intake manifold.
Of course the D16A6 manifold will work, but you can use a newer model intake manifold such as one from the D16Z6 (offers better flow characteristics).
That's it for parts!

Since your engine harness is hacked up beyond what you feel comfortable repairing and working with, then you will need an engine harness that would be for your STOCK engine.
This will be an engine harness from a 90 or 91 (88 and 89 are different) DX.
(The harness from a 1990/91 sedan DX/LX or CRX DX may work as well.)
You might think that an engine harness from an Si would be a good choice since it's from an MPFI engine, but it simply won't work. The firewall plugs have the wires in the wrong places so that is why you need your stock harness.

Then you will need to do the DPFI > MPFI conversion yourself.
Don't forget to flip the wires in the TPS connector!

 

with that being said, if i use a dx harness will it plug into a the si ecu since its still obdo correct? and with using a dx harness i will have to mess with a few wires for the mpfi conversion and how about the dizzy plug since its dx to si?

and ive read that the z6 manifold is good on this swap but will everything hook up ok since its form a new motor?

thanks for the great info..really!

 

your cabin harness will need wires added to run a si intake, injectors, and ecu

 

To change the game up..

Is there an alternative head I can swap on this d15b7 block to make things easier with still going mpfi?

 

Not sure what exactly you're trying to make easier by utilizing another head but maybe saying this will help you understand a bit more. MPFI is independent of the head as the injectors are attached to the manifold.

 

Game changer.. i picked up a full complete b18 gsr vtec motor with bottom fully build for 600+hp turbo setup with tranny and everything but ecu shift linkage and a few other parts..and made out with a few thousand dollars worth of name brand b series parts! All for $750 I freakin scored last night!!!

Just going to sell the d16a6/d15b7 motor make a few bucks back

 

b7 and a6 head are the same btw

 

Well now you are REALLY going to need the DX engine harness!!!
Just like the situation before, the GSR is MPFI.
You will need the DX harness and then convert to MPFI.
The ECU plugs won't plug into whatever B18 ECU you plan to run so you also need a jumper harness.

 

^I was actually going to say the same thing last week. The game changer just added a bit more work.

 

Yeah, hopefully his "built for turbo" bottom end isn't some low compression garbage.
He also gets to deal with engine mounts, axles, coolant hoses, and he didn't even mention if the engine came with a transmission.

I would sell the engine. OP seems like they are in over their head and they just don't know it yet.
The cost alone for a good transmission and a hydro conversion is going to be a shocker.