85 Riv to 87ecm and harness

[sailor77]

I am chainging my 85 Riv to a Regal Hot Air set up. I am planning on changing to an 87 ECM and I also have the wiring harness off an 87 GN. What else will I need besides the MAF and coil to do the job right?

 

[GNVenom]

If you're using an 85 engine, regardless of the ECM you use, the 87 harness won't work. The 85 RIV that uses the 85 hot air engine is almost identical to the 85 GN harness, except the RIV has the O2 sensor in a slightly different location, and has a few extra (unused) wires in it.
Use an 84-85 engine harness, it'll plug right in.

-John

 

[sailor77]

ok, So please explain why the 87 harness would not work. I am putting the motor in a Jeep. The haness contains the sensors and relays, also have the fuel rail and injectors, ecm, ign/coil. All I would need to get is the MAF from an 87. Everything would plug right in.

 

[GNVenom]

The 85 engine has sensor in different locations; TPS and IAC are in the rear of the engine, CCCI is in front, alternator is on the passenger side and uses a different connector, EGR uses a different connector and the general layout is different in how the harness is placed on the engine. The TPS wiring is reversed, and there may or may not be wiring for the powermaster tied into the harness. The 85 engine has no electric coolant fan, so the coolant fan relays and delay relay won't function.
But besides all that, the engines are pretty much the same

-John

 

[sailor77]

Thanks, that makes a little more sense. I guess I will have to use the current harness. I do have a few more questions.

Obviously one is able to install an 87 ECM into an 85. In doing one is able to wire up electric fans off the 87 computer. Then why would not the 87 ECM and harness control electric fans?

What wires are you refering to as "un unsed" in the Riv harness?

If not using the power master system, will it set an SES light or be any problems?

 

[GNVenom]

The 87 harness will control the electric fan, but there is no electric fan on an 85 car. If you are attempting to put an 87 harness on an 85 engine, it won't fit because of the layout. You would need an 87 engine layout to use the 87 harness-only.
No SES codes are set with or without the powermaster system in place.
The RIV has an odd connector used for "leveling" system that was never actually in the ECM code, but the wires were in place on the harness and didn't connect to anything. Also, the analog dash RIV had an unused connector, like the Regal, for a digital dash turbo boost light. Conversely, if the was fitted with the digital dash, the MAP connector was unused and not connected to anything.
-John

 

[sailor77]

OK, so I use the 85 harness, with the 87 ECM, 87 MAT, 85 MAF, 85 Cal Pak, Custom chip. I have to add a pins to the harness for the MAT and fan relay.

If at the same time I change my coil and ign mod it an type II it is my understanding that you (caspers) make an adapter for the ign mod to plugin, and I must swap two wires to make the coil fire correctly.

How am I batting?

 

[GNVenom]

Batting 90%
You will need a MAF sensor for the 87 car.

And everything else will fall into place.

-John Spina

 

[BLACKHAWK38]

CASPER'S new CAM sensor cap with LED?

Originally posted by GNVenom
Batting 90%
You will need a MAF sensor for the 87 car.

And everything else will fall into place.

-John Spina

HI JOHN SPINA< Sorry to hijack this thread but as long as your in here , How is the new cam sensor comming along?

Thanks and REGARDS<> Blackhawk38