Electrical harness for track car

JohnJL · 12-17-2005, 03:31 PM

The wife still has the camera, so no pics yet of the new baby (GR 82SC RoW import) but I've dropped the engine already and have the AC out...

For those who have converted for dedicated track duty, did you just strip out the unused electrical circuits, or did you take everything out and use a fresh harness? If so, what did you use...build from ground-up, or start with a "Painless"-type universal kit?

I have used a Painless kit before to replace all circuits on my FJ40 and it was anything but painless...for example, I spent hours on the phone with the Painless rep (good service at least!) explaining how every time I turned on a turn signal, all the signals flashed...turned out I needed to solder in some diodes...which was entirely undocumented in the lit...seems everyone would have that problem, right?!?!

Anyway, I am a bit circumspect about leaving the existing harness in as I am concerned I might accidently miss a circuit that needs to be terminated and end up with fire...

What's the consensus...tear it all out and re-wire? Any kits with better quality wire and fusebox than the Painful kits?

BTW...what a sketchy-looking fuse panel!!!! The care is in mint condition, so no worries about the quality, its as-new condition. I am just surprised at how those blocks look!

ianc · 12-17-2005, 10:53 PM

I can't see the benefit of replacing the harness. You aren't going to get any appreciable weight savings from it, and it would be one HELLUVA lot of work and expense. Why bother? Everything you remove, just clip the wires and tape over the ends if you're worried. I don't see how you can go wrong here,

ianc

JohnJL · 12-18-2005, 12:35 AM

Well, the CIS is gone now, so all of those circuits are useless. Megasquirt is replacing all those circuits and I don't need license plate lights, radio, CD, clock, fans, internal lights, AC, etc. There are just so many circuits I don't need, it seems an unnecessary risk to keep the old harness "hot" when I really only need a few circuits.

That old fuse panel look skind of sketchy to me too...even tho its only 82 and in good condition.

Seems like it might be worth $300 to have a simplified, updated electrical system.

RoninLB · 12-18-2005, 03:45 AM

I did the engine compartment with a carb install. It's a 6 circuit Blue Sea Systems glass fused optional fuse panel with a ground strip & power strip. The power feed comes from the starter lug. I used AWG tinned oversized marine wires and used silver solder for the connectors. Each circuit is capable of handling huge amps.

Painless is a POS compared to this panel. It is overkill but will be capable of handling anything. C2 spoiler power, MSD, ++++.

Stock is a POS imo.

RoninLB · 12-18-2005, 03:52 AM

The Pertronix dizzy trigger has a connector bus. It's a wham bam for troubleshooting, r&r, etc.

jmshepard · 12-18-2005, 06:41 AM

JohnJL,
This is a background project for my car. There is good reason to go this route not only for the unused hot circuits. Also, the 25year old wiring is getting very bittle and can fail. Not only could it cause fires but bad connections result in electrical gremlins that are hard to track. The following link goes to a source for wiring:
http://www.ynzyesterdaysparts.com/
For a track car I was looking at an early 911 harness.
Jim S.

len911 · 07:00 AM

I just went through this last year in my track car. PO had pull most of harness to paint car. I removed the OEM harness all together and ended up using a Painless Wiring 8 circuit kit. Moved fuse box under dash, ran new harness front and back. Re-used rear part of OEM harness to be able to use 14 pin connector. Spliced both by starter. All electricals work, including gauges, lights, etc. Car is street legal. Not for the faint of heart. You better know how to read a wiring diagram and figure out how circuits work. Spent about 60 hrs on it. Including some pictures... BTW, OEM harness was 21# vs. 7# for the Painless kit. Can it be one? YES! Enjoy! Lou

DUK · 12-18-2005, 07:00 AM

JohnJL, I used a company called American Autowire. They actually build a harness for the street and it's sold at Watson Streetworks. They have awesome customer service and knowledge. They both have websites also. americanautowire.com and watsons-streetworks.com

HawgRyder · HawgRyder's Garage

If for no other reason....get new wires to remove the "shorting" possibility.
The old wires have rubbed and hardened over the years.
New connectors and fuse blocks with newer style fuses will be more stable.
The old style fuses can jump out of their holders over hard bumps.
With new wire and correct holders (wire looms) you will avoid fires.
Enough reasons?
Bob

JohnJL · 12-18-2005, 10:55 AM

Thanks all, great sources here. For others following, here's another related thread, though it didn't have the sources mentioned above.

Thanks!

race car wiring

JohnJL · 12-18-2005, 09:45 PM

Hey Lou,
I did something very similar to you on my old FJ...I am also going twin-plug and wee your coil towers there...what are you using to trigger? Details of your ignition system? More pics!

911pcars · 12-19-2005, 01:01 AM

MHO. If you can plan accordingly and are conversant with electrical circuits, I would get rid of the entire system, then rewire it. Plan for accessibility, conductor protection (away from crumple zones) and access to repair and troubleshoot circuits should the need arise. Use a modern fuse box with blade fuses and install in the interior to shorten the path toward front and rear circuits. Use distinct wire colors to ID circuits (maybe even the same factory colors would be a plus) and draw a map of your finished system so you or the next owner can remember/understand where the wires go. Use LED tail/turn signal/brake bulbs to reduce the current requirements; LEDs can use lighter gauge wires too.

Sherwood

len911 · 12-19-2005, 03:25 AM

Quote:

Originally posted by JohnJL
Hey Lou,
I did something very similar to you on my old FJ...I am also going twin-plug and wee your coil towers there...what are you using to trigger? Details of your ignition system? More pics!

John, the system is an Electromotive HPV-1 using their sensor/splitter cable and a crank wheel from Clewett. Pretty standard set-up. Using an OEM round relay to power up coil packs via control panel in dash. Make sure you have good grounds as spelled out in the installation manual. Will post some pics from home tonight... Lou

len911 · 12-19-2005, 12:37 PM

John, including a couple of additional pictures of my setup... Relay is located on firewall, right side. Modules mounted right up to firewall. Ran extension wires from modules to side panel to facilitate reading of advance curves. Just some custom "bling"... You can see the 3 prong connectors that connect to the sender. Lou

JohnJL · 12-20-2005, 12:34 AM

Very nice, thanks for the extra pics.
What's the "STEFS" can on the right?

len911 · 12-20-2005, 02:46 AM

Just my oil catch/breather... Usually show up on Ebay. Lou

Brant · 12-20-2005, 06:56 AM

New wiring is peace of mind...
a lot of work, but there is some weight savings to be had also.
We first drew out a full wiring diagram of what we wanted, and then measured lengths and guages.

We bought all of our wire from one of the air craft supply places.
Spruce Supply, I think it was. The aircraft wiring is a tiny bit lighter weight insulation and of high quality.

Here is our entire fuse panel for a carbed car with alternator and guages:

Brant · 12-20-2005, 06:57 AM

single power wire for 4x tail lights (grounded to chassis) in order to save Weight!

Brant · 12-20-2005, 06:58 AM

lighter battery cables which were calculated for wiring guage and run-length:

Brant · 12-20-2005, 06:59 AM

Last one of more wiring harness...

(snuck my custom pedals into this shot also)