Ok heres the deal. I am putting a complete swap from my h23a1 in my 92lude Si to a h22a complete swap from hmotorsonline.com it says it comes complete with everything including a p13 ecu and engine harness. My question is can I use a chipped p72 ecu with hondata s300 with the p13 engine harness. Or if I can use the h23a1 engine harness? If this sounds like a mundane question let me know and I can try to reword it if it aint clear.
Thanks for the help

 

as long as ur ecu is obd1 ur ok. u can hook it up without a harness if im not mistaken. the p72 will work along with the p13 or a p28.

 

You'll need to take the oil pressure switch plug from the RHD harness and add it to the H23a1 harness. A RHD harness wont work in a LHD car.

 

So i have a question. If you decide you want to use a p72 or p28 ecu, can u just swap in the new ECU? Or do you have to use the old p13 and the new ecu??

 

NVM no one answer just read the huge thread about h22 ecus! That was a baller thread!

 

Ok so if I understand correctly, the existing usdm h23a1 wiring harness will work with either the p13 that im getting with the engine or the chipped p72 that I can get? All I Have to do is add the oil pressure switch?And I did a good search using many keywords and read many posts but im still unclear. Which thread are you talking about XMOD?

 

What is the name of that thread....

 

Heartsquad, you are correct, just add the pins for vtec to your harness, and you are good to go.

 

https://honda-tech.com/forums/honda-prelude-4/definitive-prelude-ecu-choice-hondata-info-post-567799/

Errr you go... Not sure if it will answer your question. It answered mine tho.

 

It's super easy, when your motor arrives just cut off the loom starting from the oil pressure switch all the way back to the big plug. Use some needle nose pliers to take out the white insert and take a paperclip or something small to pop the metal pin out. Cut the black ground wire coming off of the plug and find somewhere close to ground it and just take the blue wire and plug it into the blank spot on your harness. I'll try to get you some pics later.

 

Thanks that clears it up so much. I have no problem building performance engines. But, when you put wires in front of me im going to laugh at you. Ecus and harness' are new to me I came from carbs and magnetos. And btw I am from Jville, but im stationed in california. And thank you if you can get me some pics

 

That's all you do with the light blue wire, hopefully though you get a harness with your motor to take the plug with this wire and the black ground from.

 

Thank you so much. Now I have a good idea of what to look for.