I have a 1990 CRX with a LS B18A1 OBD0 swap, the motor is a 91. The guy i bought the car from has a P75 ECU in it right now and the harness is all sorts of messed up, but i just picked up a PR4 ECU and a new harness with directions to do it the right way, not spliting into other wires. So is the P75 or PR4 a better way to go with it?

 

I would use the Pr4.

 

your better off with the pr4 ecu...cuz thats the ecu for that engine....p75 is obd1

 

aight thanks man, i guess i have some wiring to do tonight

 

pr4 is the easy way to go, but the engine will make more power and have a higher redline if you convert to obd1 p75 what year is the ls you are installing???

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Fern413 &raquo;</TD></TR><TR><TD CLASS="quote">your better off with the pr4 ecu...cuz thats the ecu for that engine....p75 is obd1</TD></TR></TABLE>

P75 is also OBD 2 as well.

https://honda-tech.com/zerothre...57564

 

its a 91 B18A1. ive got it in the car and im tryin to get it started but for some reason it will turn over but wont actually start, i just bought a new distributor for it today and i had spark for a little bit and im not 100% sure cuz i just decided to call it a night, but im thinkin for some reason i dont have spark on the new distributor now too, just about ready to sell the thing cuz i dont have the time/patience to mess with it much more.

 

okay so i know theres really not much of a difference between the pr4 and the p75 ecu's i have. currently the p75 is wired up, but i noticed the head is pr4 on my b18a1, the guy was running a td-85u distributor and when i went to replace it i found the correct one was a td-23u so i switched em out, but im basically wondering if that obd2 p75 im running could be the reason behind my ignition timing issues on the PGMFI B18A1?