I have a 97 GSR in my 94dx coupe. My friend told me that a P72 ecu is the wrong ecu for my 97gsr motor. Is he right??

 

ummmm.....sorry but your buddy is wrong on that...just as long as you get an obd1 p72 (gsr ecu), you will be fine! tell your friend that he doesn't know jack...just make sure you get a gsr ecu (p72) out of a 94-95...cause 96-00 is obd2...that won't work...good luck with the car and your friend there...

 

kewl thats what i though. now i just have to find out if my cousins p72 is obd1.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by ATrin &raquo;</TD></TR><TR><TD CLASS="quote">kewl thats what i though. now i just have to find out if my cousins p72 is obd1.</TD></TR></TABLE>

Well just try plugging it into your harness. The plugs are different for OBD1 and OBD2 so if it doesn't fit then its not OBD1

 

yea i'm gonna swing by and pick it up. so there's no issues running an obd1 P72 on a 97gsr? just want to make sure. thx

 

nope thats the best ecu to use, unless you buya p28 and get it chipped.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by H9Omega &raquo;</TD></TR><TR><TD CLASS="quote">nope thats the best ecu to use, unless you buya p28 and get it chipped.</TD></TR></TABLE>

The only time a rechipped P28 can even benfit a GS-R engine is if the GS-R engine doesn't have the stock dual butterfly intake manifold. If you have the stock GS-R intake manifold then KEEP that P72 ECU and make sure the knock sensor and secondary/IAB wires are hooked up for optimal performance until you begin tinkering with different cams, intake manifold, etc.

 

I know what the iab/butterfly does but what does iab stand for? I don't plan on getting an aftermarket manifold so, yea i'll just pick up the p72. i need to get the iab's and knock sensor wired though.

 

Nope its odb2. damn!

 

Intake Air Bypass

something to remember with the wiring of the secondaries. OBD1 p72 sends ground to the IAB solenoid. The other wire gets hooked up to a switched positive (easiest place to hook to is at the fuse panel).

edit: and the KS has to be wired up, it'll fall on it's *** without....

 

if your model is a dx you are gonna have to wire up knock, vtec, iab to get the p72 to work correctly

 

If for some reason i can't get a hold of a P72, what will i need to do to my P28 to make it run correctly??

 

wait, uhhh I'm confused...why are pple telling him to get an ODB1?????

If u have a 97 GSR motor, u want an ODBII P72, I do believe...., wasn't ODBII enstatd 96+? Unless u have a conversion harness ((ODBII &gt; ODBI)then everything would be peachy) the plugs won't even fit into the ECU :-\




Modified by Syndacate at 2:02 PM 7/28/2006

 

so then i need a obd1 to obd2 conversion ecu harness???

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Syndacate &raquo;</TD></TR><TR><TD CLASS="quote">wait, wth, why are pple telling him to get an ODB1?????

If u have a 97 GSR motor, u want an ODBII P72, I do believe....but like they said, unless u have a conversion harness ((ODBII &gt; ODBI)then everything would be peachy) the plugs won't even fit into the ECU</TD></TR></TABLE>

He has an OBD1 car/harness

 

you wouldn't want to go from obd1 to obd2. that will make everything much more difficult. if you are obd1 already, stick with it. just look online for an obd1 p72 or something, don't waste the money on a obd1 to obd2 conversion harness...waste of time and money...

plus it is fine to run an obd2 motor on an obd1 ecu...nothing wrong with that...just less wiring...

but yea...do not waste money on a conversion harness from your obd1 vehicle to an obd2 ecu...trust me..it'd be better off finding yourself the correct ecu for your year...OBD1

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by SkoundrelUSA &raquo;</TD></TR><TR><TD CLASS="quote">

He has an OBD1 car/harness </TD></TR></TABLE>

Yeah but he's got a '97 GSR...isn't that an ODBII engine...so wouldn't u need a ODBII &gt; ODBI harness....

 

nope, use the obd1 computer

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Syndacate &raquo;</TD></TR><TR><TD CLASS="quote">

Yeah but he's got a '97 GSR...isn't that an ODBII engine...so wouldn't u need a ODBII &gt; ODBI harness....</TD></TR></TABLE>

No.

Even though the engine came out of an OBD2 car it's easier to make it OBD1.

"How?"

Well first of all you can keep the 97 GS-R engine harness - it plugs right into your shock tower chassis harness plugs on the 94 Civic.

From there you can run the wires for VTEC, IAB, and knock sensor from the chassis harness plugs on the shock tower into the correct ECU pin locations and run an OBD1 94-95 GS-R P72 ECU and like magic - the engine is now OBD1!!!

This is exactly how I run my 1998 B18C5 swap - I kept the 98 engine harness and run a rechipped P28 ECU, which is OBD1, and it runs swell. I run a P28 because I don't have the dual butterfly intake manifold like the GS-R does.