Completing the Porsche 917 Replica build.

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I had to get exhausts on the car. The easiest way was just to take the car to someone who builds custom exhaust. I loaded the car onto the trailer and took it through to Bosson exhaust. They were an outfit that specialized in performance bike exhausts.

As we made custom water-cooled exhaust for the marine engines I had a set of flanges that bolts onto the heads. Chris Bosson only had to build the headers and the exhaust system after the collectors. A few days later Chris phoned me up and told me the exhausts were done. I went to collect the car. Chris built a serious set of exhaust for the car. He made the primary exhaust headers 50-millimeter diameter. After the collector, it was 76 millimeters all the way to the back.

Usually, people will say exhaust should not be too big, these pipes were just right. On a Supercharged motor, you need big pipes to get the gas out as quickly as possible. Too big pipes you lose the tuning effect and the gas does not get pulled out of the cylinders. These pipes were perfect. When I got back to our workshop I started up the car. It was really loud but it sounded great. These exhausts talked the talk.

Connecting the gearbox to the wheels

The rear hubs that came with the kit for the 917 were meant for Volkswagen CV joints. The Tripod joints that came with the Xtrac 396 gearbox were huge as they could handle a lot of torque. I had to re-design the hubs to and spec bigger bearings to take these new tripod joints.

Porsche 917 Replica hub for Xtrac tripod joint modeled in CAD

After I had these manufactured all that was left was the side shafts. Xtrac sent us the drawings for the shafts and we machined them inhouse. I assembled the complete hub assembly and everything went together as it should.

Shifting the gearbox

All I still needed to do to get the car to the point that I could drive it was the gearbox shift system. I got the box out with all the loose goodies. There was a controller, mounting with pedals for the steering wheel and a sensor and gear position display.

I mounted all the components and started with the wiring. Later that day I switched on the ignition and tried to do a shift. I heard an aggressive knock sound from the back of the car and the display showed I was in first gear. I took the rear wheels off the car and started the car in neutral. It sounded beautiful and the vibration of the engine made the Adrenalin pump though my body. With the clutch released I engaged 1st gear. I let the clutch pedal out and the rear hubs started turning. The engine was only idling at 1200 RPM. I revved the engine up to 6000 RPM and shifted to 2nd gear. I sounded so brutal, and I selected 3rd then 4th all the way to 6th gear. The sound of the spinning hubs came through the sound of the engine.

This was a really good feeling. It wasn’t long and my boss was standing next to the car. He looked like a child seeing a new toy. I fitted the rear wheel and put the car down on the ground. My heart was jumping around in my chest as this was going to be the first test drive of this brutal machine.

The first test drive

I drove the car out to the cement apron just behind the plane hanger. I drove the car in circles shifting gears and everything worked properly. Next, I gave it a bit of throttle. This car accelerated like nothing I have felt before. This was a beast. I started to get the feel of the car and threw the car sideways under power and the back end stepped out nicely. I ended up though very nice donuts leaving the apron with a cloud of smoke. This was fun, a lot of fun.

The first track test

We received the body from the painters and we fitted it to the car. Everything went together as it should. It was a few weeks later and the car was done. Ready for its shakedown test at Killarney international raceway in Cape Town. This was a glorious day, we had nice weather and the car was good.

This is me getting ready to take the Porsche 917 out on the track.

This was my first time to ever drive a car on the race track. I was hyperventilating. The first lap or two I drove the car fairly slow. I needed to get the feel of the car before driving it in anger. This was an absolute beast, I have never experienced something like this. I would never in my wildest dreams be driving a car like this. You forget about everyone and everything and become one with the car. This was one of my highlights, something I would never forget. The was a really good day.

Some video footage of the first track outing