Van

Or, how to add lightness to a race car!

So, as I'm debating with myself on whether or not to put the dash back in my car, I thought it would also be a good time time trim back some of the unused wiring to remove some weight. I pulled out the fuse/relay block, and, oh my - that thing is heavy. Now, I'm only using 6 fuses and 3 relays to keep the car running, so I thought I'd take the thing apart and see what makes it so heavy. The answer is, there are many layers of copper bus bars in there! And the good news, I only need about 20% of them.

The bad news... I'm not completely sure that I'm going to be able to get the whole thing back together... But, if I can't, I'll just wire up some aftermarket fuses and relays.

VirginiaF1

Van's TOP 10 Responses

#10. Picture #2 looks like my checking account..
#9. Always educational Van, thanks for the inside scoop..

Who else got game?

FrenchToast

The fusebox is a scary and mysterious place. Seen one dismantled before.

It may be time to redo your entire harness. And also, considering the trend of copper's value, all that unused copper must be worth at least four million dollars.

I wonder what a fusebox looks like on modern cars.

I see you have the very rare 944 GT3 Turbo Carrera S. It says SP1 - you have two spec cars?

I remember I saw a real 944 Turbo Carrera GS 4S Targa CS 2S RS ST STR E L S RSR R T once.

Van

Just enough for a set of track tires!

So, this red car - this SP1 car - is the ChumpCar we built last winter and raced at Watkins Glen (in the snow). We came in 51st out of just over a hundred. But, more importantly, the car held together and worked well!

One of my Chump teammates (there were 6 non-racers on the team, but they had done DEs) was so stoked, he had to drive in the next PCA race, so we set it up for SP1 - put on 350# springs and 30mm torsion bars, plus Toyo RR tires. Now he's gone and bought an SP3 car, and the ChumpCar has been sitting around (a few other teammates have been using it for DE).

Well, I'm registered for the NJMP race next weekend, and the orange car is, obviously, not ready - since the wiring, dash, engine and suspension are all apart. So I'm going to try the ChumpCar in SP1. It's good to have a backup car!!

Dougs951S

Not as rare as my genuine, factory prototype 944 Super Turbo CS 4S RSRT8 oh wait...


Amazed how much crap is in that box..did you weigh it by chance Van?

william_b_noble

suggestion: instead of destroying a fuse box (AKA "CENTRAL ELECTRONICS"), why not remove the box and all the associated wiring and then put back only what you want - if you are only using three fuses (ignition, fan, everything else?) just wire it accordingly. The DME cable is pretty separate so you can leave that alone and just remove the other two harnesses.

Van

William, that *is* what I'm doing - only putting in the traces I need for my few relays and fuses.

You're right about the DME harness - that is separate and stays the same. The only wires I need going to the back of the car are for the fuel sender, fuel pump and brake lights. Only wires I need going forward are for the ignition coil (however, I'd have to take the bumper off to get most of that harness off).

In the cockpit, I need the ignition/start switch, leads for coolant gauge/light; oil pressure gauge/light; gas gauge/light and alternator light. Oh, I need wires for the cooling fan and wipers, which will be manually switched.

I will have start and finish weights when I'm done (e.g. I have another, complete fuse block to compare my modified one with!)

harveyf

Interesting Van. So now I'm beginning to see what the Porsche wiring diagrams are showing as a grey box with a bunch of horizontal "trunk lines" that have vertical drops down to wires and components. The horizontal lines are equivalent to the buss bars. Cool!

mytrplseven

aaahhhahahahaha. Deja vu. I had a bad trace where it contacted a particular relay and, being 50% adventurous and 50% stupid, I took my fuse box apart. Bad idea. After an entire day of fenigelling, a little tape to hold traces in place and some cussing, I actually got it back together. It actually worked. I did sneak up on it where voltage was applied (smoke test) but I've had no further issues. I consider myself lucky and swore never to do that again. :P

curtisr

When it comes to my '82 928 I'd have to say that 'what's inside my fuse box' is the source of all of my car's troubles and the answer to all of the same. I hate it.

Gawernator

You're gonna make me cry

f1rocks

You'll save enough weight with the fuse block to add the radios I'm bringing with me this weekend!!

See you Thursday! I'll have my official shirt on.....I'm bringing that SP1 in for major scrut work

Van

You can scruit that thing all you want!! But I think we should find Henry illegal... did you see he got my photo credit in Panorama?

ditch68

Holy crap, that's a lot of copper.

I don't mind rebuilding engines, pulling clutches, transaxles, anything mechanical.

But I HATE ELECTRICAL WORK. Therefore, this thread represents the closest I will ever get to seeing the inside of a fuse box on a 944. I don't even like changing fuses.

Jeff

f1rocks

I saw that!

I'll bring you both in for good measure. You should come down for the 944 cup nationals at Daytona in October! I'm sure the orange car will be done by then.