87 to 86 951 Harness Conversion
07-02-2018, 08:12 PM
#1
Pro
Thread Starter
87 to 86 951 Harness Conversion
After having a bit of a harness fire in my 86 951, I just sourced a very nice used harness from an 87.
Noticed two differences between the two harnesses. (Well, 3, if you count the fact that mine is melted and the other is not!)
1). The instrument connector on the 86 car is the early red 4-pin connector, compared to the flat 8-pin connector on the 87 harness.
2). The 86 car does not have the oil level sensor, and the 87 harness has the associated plug.
Looking at the schematics for both years, it would seem that the two differences are related. So the question is, how do retrofit the 87 harness to fit my 86 car? Need to remove the plug for the oil level sensor and adapt the 8-pin connector to mate with my car’s 4-pin connector under the dash.
After doing some searching, I found posts indicating that others had accomplished this conversion, but couldn’t track down the details on how to execute it.
Any help would certainly be appreciated!
Noticed two differences between the two harnesses. (Well, 3, if you count the fact that mine is melted and the other is not!)
1). The instrument connector on the 86 car is the early red 4-pin connector, compared to the flat 8-pin connector on the 87 harness.
2). The 86 car does not have the oil level sensor, and the 87 harness has the associated plug.
Looking at the schematics for both years, it would seem that the two differences are related. So the question is, how do retrofit the 87 harness to fit my 86 car? Need to remove the plug for the oil level sensor and adapt the 8-pin connector to mate with my car’s 4-pin connector under the dash.
After doing some searching, I found posts indicating that others had accomplished this conversion, but couldn’t track down the details on how to execute it.
Any help would certainly be appreciated!
07-05-2018, 07:19 PM
#2
Rennlist Member
Yep, very much related. See post 4 in the thread linked below. If you can salvage the old 4 pin connector, you could graft it on the new harness. Otherwise I'd be tempted to use any old connector on both sides, like a weatherpack or molex...
https://rennlist.com/forums/944-turb...rpm-meter.html
https://rennlist.com/forums/944-turb...rpm-meter.html
07-05-2018, 11:03 PM
#3
Pro
Thread Starter
Yep, very much related. See post 4 in the thread linked below. If you can salvage the old 4 pin connector, you could graft it on the new harness. Otherwise I'd be tempted to use any old connector on both sides, like a weatherpack or molex...
https://rennlist.com/forums/944-turb...rpm-meter.html
https://rennlist.com/forums/944-turb...rpm-meter.html
Been doing some more researching since I originally posted and had tentatively come up with your plan”A”. I don’t believe my harness damage extends to the original plug, so my plan is to de-pin pins 1-4 on the flat 8-pin on the new harness. Then transfer those wires to the 4-pin plug I can hopefully salvage from my old harness. Now I just need to source the right pins to fit the connector.
By the way, I’ve been re-reading your write-up on your integration of the Zeitronix WB into your harness, as I’ll need to install all of my mods on the new harness once it’s installed. So, thanks...again!
07-06-2018, 10:31 AM
#4
Rennlist Member
Glad the Zeitronix info helped. As far as I can tell, those user pages on RL are locked up and I can no longer post new info, which is too bad. The pins in the red 4-pin connector are blade style connectors. If I had to guess I'd say they are 111971985 but very hard to know without having them in hand. You could always cut the old connector off with a few inches of wire and just solder and shrink tube it onto the new harness wires. I was just in Colorado Springs by the way. The top of Pikes Peak made me light-headed. I have no idea how people drive 100mph without oxygen and with jaw-dropping cliffs everywhere! Crazy. 
07-09-2018, 08:39 AM
#5
Pro
Thread Starter
Quick question, Tom.
When I swap the old 4-pin connector over to the replacement harness,what would I do with the extra wires dedicated to the oil level sensor? Cap them? Leave that 8-pin plug in place and just branch off the 4 wires I need for the red plug? And what of the oil level sensor plug itself? Can I just cut it from the harness?
Well, that was more like 5 quick questions...
Thanks for your help!
When I swap the old 4-pin connector over to the replacement harness,what would I do with the extra wires dedicated to the oil level sensor? Cap them? Leave that 8-pin plug in place and just branch off the 4 wires I need for the red plug? And what of the oil level sensor plug itself? Can I just cut it from the harness?
Well, that was more like 5 quick questions...
Thanks for your help!