Pressure Problems: A Post-Race Autopsy

1w ago


After the chaotic events of the Ter Apel race, it was time to regroup and reassess. My tussle with the rebellious driver's side screen, and my general inexperience with driving the car at speed had clouded my judgment of the day's running, preventing me from properly judging the car's performance.

Frustration caused by the rogue screen ruined the day for me.

My first ever heat in the car saw many competitors crashing each other out, including a car violently flipping through the midfield, immediately making a big impression on me. After misjudging my unassisted brakes and missing my braking point, I even hit the wall, and was later black flagged for the errant screen.

Especially after watching my father get taken out right in front of me, I decided to take it easy and simply gain some seat time in the second heat. As I was running without a transponder to save money, I wasn't going to make it into the final anyway, so I had nothing to gain from driving like a disoriented maniac again.

The power shortage was painfully obvious in hindsight.

With the screen fixed by removing the gas strut supporting it and elongating its prongs with a section of rubber hose, I did exactly that. Because of this cautious attitude, I failed to notice the acute lack of power coming from the DT-R's 1.8 turbo engine.

Fresh battle scars incurred at Ter Apel.

Since the clutch was almost impossible to operate, I remained in second gear all around the course, making me attribute the lack of power to nothing more than turbo lag. As it turned out, I was sorely mistaken.

The culprit: a loose turbo.

As we started the car up again a few weeks later back at our workshop, we noticed an inordinate amount of noise, even more than usual for a straight-piped car. Suspecting an exhaust leak, we went over the car and didn't take very long to identify the issue.

Through the hole in the firewall, I was able to see the turbocharger, which as it turned out was hanging from the manifold by a single fastened nut.

Unsurprisingly, the gasket between the two had been chewed up, so simply screwing the thing back on wasn't an option. Moreover, the incredibly cramped engine compartment made it inaccessible to anything but the tiniest hands anyway.

While my father concentrated on dismantling the parts needed to reach the turbo, I started work on the brakes, which were up for another rebuild after sitting in a damp, dark garage. Being one of the few cars to run disc brakes on a four corners, an unusual feature for a dirt track car, the rears had started seizing again. I sanded down all the discs, removed any rust present, and even splashed some primer on the heat shields to eliminate further corrosion.

With the brakes sorted once again, it was time to start preparations for the integration of power assisted brakes. Originally, the car had built to house a 2.0L 16V, carbureted engine, and it showed.

When the idea to run the G60 turbo came about, a lot of concessions had to be made to fit parts like the intercooler, the turbo, the bulky injection system and all the associated piping and ducting. As a result, the injection system ended up in the passenger footwell and the wastegate ended up where the brake servo would normally be.

As you can see at the bottom, the wastegate was directly in the way.

In order to make the large, drum-shaped servo fit, we would have to relocate the wastegate. I suggested using one of the many bits of scrap metal lying around to move it aside. Dad duly obliged, using a small section of pipe, constructing a flange and making some gaskets to get the wastegate away from the brake fluid reservoir, and closer to the engine.

The relocated wastegate.

Making the distance from the exhaust manifold to the wastegate longer would undoubtedly make boost levels rise slightly, but this was a risk we were willing to take. Meanwhile the turbo received a newly fabricated gasket, making it possible to start refitting the exhaust manifold, exhaust pipe, and intake manifold, reconnecting the vacuum lines and reattaching the throttle cable

Just as work on the car was being finalized, I discovered a local motorsport convention was looking for entrants for its live exhibition. Vrije Standaard was among the many classes on display in the live action arena, and as luck would have it they were looking for two more cars to complete the grid.

Enthusiastically, I applied for the event. Almost immediately I received a positive response back, and we were in. With both cars about 95% done, we had our work cut out for us to make the deadline for a full weekend of friendly competition.

THANKS FOR READING. NEXT TIME: Coverage from the 2019 Leeuwarden Racing Expo