After thoroughly checking the bike over we declared ourselves ready and “cautiously optimistic” for FoP 2023. We should have known better!
Opening the batting with a 6.87 @ 205mph drew applause from the commentators, and qualified us #2 behind Eric Richard, but a quick glance at the datalog showed we still had just 4psi (out of 63psi overall) from the big turbo, meaning the small one was doing all the work, same as at the Easter meeting. Due to the way compound turbos multiply boost, we were looking for 18-20psi from the big one (to make 63psi overall), but we could see that the big wastegate was wide open right from the launch, hence the low boost and lacklustre 60′ time.
We tried again with higher settings in the controller for the big wastegate (to hold it more closed), but it made no difference: 6.84 @ 204.
Then bingo! We spotted a broken wire from the boost controller. This HAD to to be it, right? RIGHT? We reconnected it, put in the original numbers and went 6.9 @ 200. You idiots! Of course that wasn’t it. Still 4psi from the big turbo.
With our 3 Saturday runs done we set about testing everything on Sunday morning. Boost controller working. Solenoids working. Sensors working. CO2 system working. Small crack in the wastegate diaphragm, but not enough to cause this problem. But wait. On the small turbo the controller is set to 32psi and gives 32psi out of the solenoid, measured on a gauge. The big turbo is set to 45psi but only gives 22psi out of the solenoid – not enough to hold the big wastegate shut against exhaust pressure. We put 60psi in – and got 22psi out. 10psi in – 22 out. What? This makes no sense.
We swapped both sensors separately with a new one – no difference. Brad O’Connor, Sean Mills and Dave Smith all tried to help (thanks lads!), but by now it’s 4pm and we’re out of ideas. The options were to race Monday and risk destroying the small turbo by overspeeding it, or go home. With a bunch of other sensors not working, we chose home. The bike needs some professional help so will go on holiday to Mark Harrison at Horsepower Factory UK to be sorted. Congrats to the tenacious Dave Peters on the win and Eric for putting up some stout numbers. Until next time!
Thanks to all our crew Mike Hand, Simon Campbell, Mick Bisson, Sarah White and to all our sponsors:
AC Schnitzer UK – the premier aftermarket tuner for BMW & MINI
AS Transport – HIAB crane services. Need a lathe moved? These are your guys.
Mobihose – hydraulic hose and service
Leeks Landscapes – class sponsor
Suffolk Pool Company – design to completion
Owen Developments – suppliers of our turbos and wastegates for many years
Horsepower Factory UK – support with our electronics