It’s difficult to know where to begin.
We had unofficial practice on Thursday, which was essential given the brake/vacuum issue that caused my crash two weeks prior to this event. The car had not been tested since the incident, so the primary objective was validation and confidence-building.
Thursday practice began conservatively. In addition, new EBC brake pads were being bedded in. The first session was encouraging; although I did not push the limits, the vacuum system performed flawlessly, maintaining near-maximum vacuum throughout the entire session. This was a very positive sign.
During the second Thursday session, the car continued to feel strong. I began applying more brake pressure to build confidence in the system. While lap times were not particularly competitive at this stage, it was not a concern—the car showed strong straight-line performance and good balance through the corners.
Friday morning’s first session was run in cool track conditions. The car felt good overall and I started to increase the pace. However, there was still a lack of confidence in the braking system. Although the car was stopping, the pedal feel was inconsistent and abnormal, even with full vacuum. Unable to identify the root cause at that point, I decided to remove the front six-piston caliper setup and revert to the original discs and calipers. Unfortunately, due to the amount of work required, I missed the second session.
Qualifying took place on Friday afternoon. On the third lap, entering Turn 2 at approximately 145 km/h, the brake pedal suddenly went hard. A quick check confirmed full vacuum, ruling out a vacuum-related issue. The car ran into the gravel at Turn 2 but, fortunately, no damage was sustained. Given the safety concerns, I elected to withdraw from the remainder of the qualifying session.
At this stage, it was clear the issue was not vacuum-related. After discussions with several BMW specialists at the circuit, the most plausible explanation was ABS-related intervention—potentially the system entering ICE or limp mode due to missing or invalid data inputs. The ABS unit is sourced from an E63 645i, a vehicle originally equipped with traction control, stability control, active steering, active suspension, and additional vehicle dynamics systems. All of these functions have been deleted or blocked, which may prevent the ABS from operating correctly under race conditions.
The plan for Saturday was to install an alternative ABS pump and further isolate the system by removing all non-essential functions. A power cut-off switch was also added to the ABS supply to allow for a manual reset if required. However, during the race, switching off the ABS unexpectedly also interrupted power to the fuel pump, requiring a rapid reset of the ABS system to restore operation.
Due to the incomplete qualifying session, I started Race 1 in 8th position in Class C. Despite the ongoing brake inconsistency, the car performed extremely well. I was able to engage in some excellent racing and ultimately finished 6th.
Race 2 started from 6th position and concluded with a 5th-place finish. The car felt very strong overall, but limited confidence under braking made it difficult to fully attack the cars ahead. Nevertheless, the race was highly enjoyable, and the sound and delivery of the V8 remains incredibly addictive.
The weekend also highlighted a few additional areas requiring attention, particularly as this was the car’s first competitive outing at Zwartkops. Overall, I couldn’t be more impressed with the car’s performance or happier with the results achieved over the weekend.
