is there any interest in a simple custom chassis harness?

[ccsdo5]

I'm just sorta curious if there is any interest in a bare plug n play style chassis harness for these cars. I planned on making a new harness for my track car because it has a lot of circuits I never use and I just want to simplify everything to avoid electrical issues in the future. I know it is probably easier to thin out a harness but if I have the car gutted for a roll cage anyway might as well use new wires instead of using 25+ year old stuff.

My goal would to have something similar to this:





I would keep the following things on the car:
- lights
- running lights
- brake lights
- reverse lights
- blinkers
- cluster (fuel level, tach, speedo, coolant temp)
- power mirrors
- power windows
- fuel pump
- anything for the engine obviously
- wipers
- electric fan

This is just what I planned on doing for my own car. I haven't decided if I want to use the stock ignition switch, light switch, wiper stalk, and turn signal stalk yet or not. If enough people are interested in something similar I wouldn't mind making multiple chassis harness' to sell. Is this a good idea or does everyone just do their own electrical work on their cars?

[Sirotto]

I would suggest keeping the or adding a line for the hvac blower. Need fog control even in a race car.

[flyboyx]

The wiring that BMW uses is of very high quality. Personally, I have never been able to buy wiring that comes anywhere close to what came from the factory. I just don't know about the longevity factor.

[Kershaw]

I save the wiring harnesses from e30s I tear down for that same reason. Very high quality wire.

[Singulaarity]

Going down this route now.. I plan on reusing the actual wiring and some of the colors to keep things remotely close to the OEM wiring diagrams, but I want my own runs and centralize everything to a motec PDM and small fuse panel in the interior.

Main reasons is going obd2 motor, integrating some CANbus functionality, and using some new weathertight connectors on everything so easy to debug. Also, I don't value my free time.

[James Crivellone]

I have one of these in the Pro3 car and frankly I'm not a huge fan, the factory did a solid job and you can can retrofit an 84 318i harness if you want to cut down on overall wiring.

[Jokester]

I would be 100% interested, especially if I can retain the HVAC blower.

[Fucatypr]

I'm just sorta curious if there is any interest in a bare plug n play style chassis harness for these cars. I planned on making a new harness for my track car because it has a lot of circuits I never use and I just want to simplify everything to avoid electrical issues in the future. I know it is probably easier to thin out a harness but if I have the car gutted for a roll cage anyway might as well use new wires instead of using 25+ year old stuff.

My goal would to have something similar to this:





I would keep the following things on the car:
- lights
- running lights
- brake lights
- reverse lights
- blinkers
- cluster (fuel level, tach, speedo, coolant temp)
- power mirrors
- power windows
- fuel pump
- anything for the engine obviously
- wipers
- electric fan

This is just what I planned on doing for my own car. I haven't decided if I want to use the stock ignition switch, light switch, wiper stalk, and turn signal stalk yet or not. If enough people are interested in something similar I wouldn't mind making multiple chassis harness' to sell. Is this a good idea or does everyone just do their own electrical work on their cars?

You need to do this EF hondas. We are having serious problems with our cars now.....my e30 is doing just fine. Make Hond harnesses and you will be able to retire in a few years.

[Jaxx_]

I would generally say that the cost of a new harness and complexity is hard to justify unless it is for a spec class, for example. Something as simple as placing a fuse panel can differ slightly from car to car, so it's hard to truly make a "one size fit all" harness that isn't the factory one. If you are doing it yourself, you're able to make decisions on accessories you'd like to have, and compromises you're comfortable with. A perfect example of this is your decision to keep the turn signal stalk or not.

For a quality motorsports harness you will be looking at 4 digits for sure, probably in the neighborhood of $4k-5k for a bespoke harness with quality components, labor and documentation included. With 10 uniform harnesses, perhaps it could be closer to 2k.

I cut up my 84 318 harness and still lost about 5 lbs. There's plenty more, but I haven't touched most of the under dash and fusebox area. The engine harness is on version 3 and still could use some work... photos attached.

[iwantspeed]

@jaxxx nice work on that harness