I have a 94 LS Automatic and I want to put in a OBD2 GSR engine. I have a OBD2 ECU and the OBD2 wire harness is still on the engine. I don't know the exact year of the engine, but I know it's at least a 98 b/c of the bumpers. Can I just drop it in and plug everything together? or will I need a obd2 interior harness as well? Thanks.

 

It is not a simple drop in. Some of the OBDII sensors are different than the OBDI sensors. (I think this primarily concerns the distributor, but I am not sure.) You'll need to find an ECU that will work VTEC, the IAB (intake air bypass for dual stage B18C1 intake manifold), AND an automatic transmission. I think some of the JDM P72 ECUs can control automatics.

 

If you want to install the manual tranny as well, then you'll need a conversion specific mount (available from Hasport), as well as numerous other components. You would be able to keep all of the sensors and harness on the OBD-2 motor, but you'll need to find an OBD-1 P72 ECU.

 

Ya, I was planning on dropping in the manual transmission as well. Sorry I didn't specify that earlier. The transmission has the mount on it. But I think I'll need the bracket that will attach the frame to this mount on the transmission, correct? I'm assuming the bracket is different for the automatic. The other parts that I have collected thus far for this project are the shift linkage, manual pedals, manual shafts and the slave and master clutch cylinders....And from a electronic stand point, basically you said I can hook up my OBD2 GSR engine up to my OBD1 Automatic LS interior harness, but I'll need a OBD1 GSR ECU?....Appreciate all the help.

 

here's an article of mine that could help you once you apply a 5-speed tranny bracket on your frame rail (making your car 5-speed transmission ready):

http://technet.ff-squad.com/hybrid.92-95.obd2.htm

 

The article is very good and helps a lot, thank you. I think I'm going to look for a OBD1 P72 ECU and go that route. Also, since I'm putting a VTEC engine in a non-VTEC car, it says ill have to wire the VTEC, knock sensor and IAB. I would go about this by modifying my plug and connecting wires to the pins on my ecu corresponding to VTEC, etc. (OBD1 ECU pinout diagram via the link you provided) Then to which plugs do I connect these wires to? I see wires coming from the VTEC solenoid, but I want to be sure. And is there a certain gauge wire that I should use? And just to make sure, my manual engine harness will hook up to my automatic cabin harness? and it will hook up to a manual ecu? Sorry for all the questions, but I like to plan everything out before I jump in. Thanks for the help.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by dannykointegra &raquo;</TD></TR><TR><TD CLASS="quote">The article is very good and helps a lot, thank you. I think I'm going to look for a OBD1 P72 ECU and go that route. Also, since I'm putting a VTEC engine in a non-VTEC car, it says ill have to wire the VTEC, knock sensor and IAB. I would go about this by modifying my plug and connecting wires to the pins on my ecu corresponding to VTEC, etc. (OBD1 ECU pinout diagram via the link you provided) Then to which plugs do I connect these wires to? I see wires coming from the VTEC solenoid, but I want to be sure. And is there a certain gauge wire that I should use? And just to make sure, my manual engine harness will hook up to my automatic cabin harness? and it will hook up to a manual ecu? Sorry for all the questions, but I like to plan everything out before I jump in. Thanks for the help.</TD></TR></TABLE>

yes, a 5speed engine wire harness shoould plug directly into your existing cabin harness (main plugs on passenger side shock tower).

when you wire in VTEC, IAB, and the KS, you wire them directly to your ECU plugs, because your LS cabin harness doesn't have these sensors pre-wired in the ecu plugs.

usually 18 gauge wire is used for wiring in sensors.