Racing at Barber
DIY Cool Suit
It gets very hot in the race car wearing three layers of nomex and a helmet and gloves. Some smart guy several years ago invented a system that pumps cool water through a shirt to keep a driver cool. Unfortunately they still charge a lot of money for their nice system.
Being cheap – I decided to build my own. As a chemical engineer, I figured I could build a simple heat exchanger.
For the cooler pump, I used a cooler I got at Goodwill. I installed a boat bilge pump form Walmart. I drilled holes in the cooler for the wires to exit and one for the line off the pump. I got clear vinyl tubing from ace hardware and some fittings to reduce to 1/4″ tubing.
Next came the heat exchanger itself. I added a piece of cloth to a t shirt that had passages sewed vertically in it. Then I looped the tubing through. There is about 20 feet of tubing in the shirt.
I added dry breaks from McMaster Carr to the ends of the tubing to reduce the water splashed in the car. #5012K115
It seems to work in the garage. We will see how it works at Barber this weekend.
944 rear shocks
Our Porsche 944 is intended to be a ChumpCar racer. So it has to meet certain rules. One of the controversial rules states that it can’t have adjustable shocks even if it came with them from the factory. We have elected to remove our very nice and expensive Koni racing shocks and swap in some KYB replacements.
The upper mount uses the stock bolt so we will reuse that. It can be accessed by dropping the suspension fully (removing the bottom shock bolt helps) and turning the head of the bolt from inside the wheel well. You will have to hold the nut with an open end wrench while turning the bolt from the wheel well.
The bottom of our Race Konis were mounted on very nice adapters that allowed the use of the spherical rod ends. To remove the adapters, we first had to support the wheel at just the right height to remove pressure from the bolt. Then the mounting bolt could be unscrewed from the adapter. The adapter was them removed from the control arm.
Since we did not have the original bolts to put the bottom of the shock back we started a quest. We measured the threads on the adapter and found they were M14 1.5. We estimated we needed 80mm of bolt. We set off to ACE hardware. They had one. But only in standard grade. I wanted a 10.9. Lowe’s and Home Depot were less helpful.
After some research on the internet we found that the factory bolt is actually 85mm. Porsche no longer sells it but BMW does. We have ordered a pair of part number 07-11-9-914-829 and will try again next weekend to get the bottom of the shock bolted in place. It is a shame to do so much work to make the car handle worse. But that is racing when you try to follow the rules.
Update: got the bolts from the BMW dealer. Also picked up several at pull a part as spares. Drilling the heads for safety wires was easier than I expected.
Adjust Headlights on Suburban
How to adjust the headlights on a 1995 GMC Suburban
The headlight son my GMC Suburban were really foggy and yellow. I am sure I could have cleaned them and gotten new bulbs but I found a good deal on replacement assemblies so I just changed out the whole thing. The first time I drove i the dark however, I realized I needed to align the new headlights. It was not obvious to me how to do it.
You don’t have to remove the grill to adjust the lights but since I had it off anyway, I took a picture to make it more clear how to adjust them.
Fist of all, the two 4mm hex pins that look like adjusters, are not adjusters. They are the pins that hold the light in place. If you remove these pins you can pull the headlight to change a bulb or something. To change the whole housing like I did you have to remove the grill.
The adjusters are hidden deep behind the grill. They have a funky star head on the bolt but I was able to turn it with a 7mm socket. I had the right socket but it would not fit in the access hole. I used a long extension on my nut driver to reach the adjuster bolt.
See the pictures for more info.
New race tires
We have heard a lot of good things about the BFG Rival race tires. They have the 200 tread wear required by Chumpcar and seems very sticky. However the set that came with our car were very worn. In fact a couple of tires had blisters after the hill climb. I ordered a new set from Tire Rack.
They arrived in a couple of days and I mounted them up last night. I am not sure if it is because they are so wide – 225/45-15 – or if it how they are made but even after breaking the bead they wanted to reseat on their own. I thought for a while I was gong to need an assistant but I eventually found a way to hold two tire spoons and the breaker bar to get the tires on and off the rims.
I stopped by NAPA and got some of their tire lubricant instead of using my normal home brew solution. I was pleased with the NAPA juice and will have to do a side by side comparison with my home made solution sometime. It was too hot last night. I look forward to running the new tires at Barber in August.
