Wednesday, February 17, 2016

White Rascal Update #6

It is alive!! We finished up the wiring last week and the White Rascal was started for the first time. The wiring was a major project for us on this car. We made the decision to dive deep into it and ripped the entire chassis harness out of the car. All non-essential wires and systems were deleted from the harness. The ABS was left alone, for now, but everything else that is not essential for a track car was deleted. We even chose to remove the problematic multi function relay in the front of the car in favor of some simple switches to activate the cooling fans.

Severely Modified Harness
Stock Wiring Harness

Before we started, the wiring harness weighed 20.20 lbs. Once we cut out the non essential items, the fuse box count dropped from 22 to 7, this is not including the 5 fuses under the dash that got deleted as well. That is 20 circuits in all that were removed. This all brought the harness weight down to about 9 lbs. The harness was laid back into the car and we made the decision to delete the stock fuse block in favor of 2 bussed fuse blocks. This allowed us to really simplify the wiring, remove a bit more weight and we have some empty spaces for what ever circuits we would like to add in the future. The two fuse blocks and ignition relay were mounted to a panel that covers where the passenger air bag used to be. We re-used the stock start button simply because it was easy and it is a cool piece, joining the start button on our switch panel is an ignition switch and one switch for each fan. Nice and simple.

After we got the car running, we wrapped up all the wiring and secured it so it wont be flopping around on track. The number one way to decrease the reliability of an electrical or plumbing system is to let it move around and get chafed/pinched. Zipties and edging material are your friend when it comes to securing wiring and plumbing. 

A look under the dash
We mounted a raceBATTERY in the spot where the AC blower assembly used to live. This moves a little bit of weight forward and opposite from the driver. 

We mounted the battery with an Xtender Bracket with no kill switch. We have two other kill switches mounted on this car. One is outside and will poke through the right side access panel at the front of the car and the other is located where the left hand driver side AC vent used to be. This configuration will allow the engine to be shut down from outside or inside the vehicle. We chose to use two of these killswitches from Pegasus Auto Racing. Properly wired, these switches will completely isolate the battery and stop the engine. 

Kill Switch Wiring Diagram

These are essentially 3 switches in one, the main part will isolate the battery. If you do a setup that just isolates the battery with a simple single pole switch, and you throw the switch with the engine running, the alternator will continue to supply power to the system and the car has no reason to shut off. So what you do is run the power to the ignition coils or ECU ignition (like we did) through the switches. Now what happens when you throw the switch is the battery gets isolated AND the engine stops because you also killed the power to the ignition coils at the same time. This creates another problem though, when you isolate the battery from the alternator it causes a large voltage spike that has nowhere to go since you shut off the connection from the alternator to the battery, this can and will damage the alternator components. The third set of contacts on the switch give the alternator voltage somewhere to go by switching the alternator output to ground the moment the connection to the battery is severed. The image above shows roughly how this all works.
A view from the driver seat
The car has been missing a steering wheel since we ripped it off early in the tear down. We finally replaced it with a Sparco Cup Wheel. This saves a few pounds of weight and allows the addition of a quick release. We do not recommend deleting your air bag in a street car, but in a race car, we consider it a necessity. We would normally run a hubQR2  but we had a sweet quick release from old stock that we decided to use. This release flips the wheel up, rather than removing it completely, this makes it easier to get in the car but the wheel stays attached to the column at all times. We can still get these hubs so if you are interested, let us know.  Yes, they are more expensive than the regular quick release kits.  8^)
That is all we are going to share for now. Look for another update next week.

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