All,

Im in the middle of a LS3 427 T56 swap on my 1991 RS and am pairing down the engine bay harness. Can someone help me identify where I should connect these four wires. Red obviously is power, black is ground, looks to be 2 additional wires, ones is green and white other is a dull light green. Also, Im pairing down the interior harness, on the AC switch itself, this brown wire, where does it go, I think its constant power? Lastly these vacuum lines, Im assuming I can just hook up to the vacuum on the intake for AC controls and the other is for the heater control valve, but which is which?

Thanks and this site has been extremely helpful!

 

Just cap the vacuum line and tuck it away somewhere. It was for the heater diverter valve to the old heater core. You can re-use it again if you decide you want heat. I took heat out of my car last year and I can tell you being cold sucks more than not having AC. I mean really, really sucks.

Behind the HVAC head unit, Brown wire with single pin connector is power from fuse panel (Heater & AC fuse). It goes through the fan speed switch and then runs out to the resistor card on the HVAC blower motor. Basically it's power for the low and medium speeds of the blower motor.

 

Ahhhh man, your thread is the one Im using to build my 427 91 Camaro... Ive been using your part number hints throughout your thread.. Im still searching for the 4 prong connector... I stripped the interior harness last night..

https://www.thirdgen.org/forums/ltx-...wktrips-8.html

 

 

Ahhhh man, now you'll have all the same problems I do. Seriously though, liking your car a lot. What wheels you got on there?

That 4-pin connector sure looks like a relay plug to me. Two large wires, two small wires. There are only a few relays on the car with the rectangle shape like that. And that relay had a constant battery power supply (red wire) so it was probably connected to battery through a fusible link in the engine bay. 95% sure it lived in the engine bay and you don't need it anymore. And if you do need it then I would junk it anyway and replace with a modern style relay. Those old-style relays are fire hazard, they were junk from day one.

 

BC forged wheels, 18x9 and 18x11.5...

 

Thank, I've never heard of them before. They sure are flexible to make what you want! There are sooooo many wheel companies out there it's mind boggling. And almost none of them make anything that will fit our cars.

Any more wheel companies like them that will make stuff for our older cars? (bolt patterns and offsets)

 

True, BC was cool, they built me these and a set for my 2017 Zl1...