Watching a 133.962mph lap around the Isle of Man TT is astonishing. Michael Dunlop managed just that in 2016 and the footage is enough to make most amateurs retire from racing. The 37.7-mile course threads its way between houses, stone walls, lampposts and thick hedges – the sun casting dappled light on the narrow strip of asphalt making visibility on many parts of the track even more difficult. As we said, a 133mph average on a motorcycle is astonishing.
What about in a car, though? Surely it’s an easier prospect? As my father used to say, “you can’t fall off a car”. It’s a different challenge but not exactly easier. Over the past few years, rally driver Mark Higgins and the team at Prodrive have been taking a Subaru to the Isle of Man during TT week to keep lowering their previous records. It started off with a fairly standard car, but recently, attempts have got more and more serious. And faster. Their latest attempt, in 2016 onboard a highly modified WRX STi, ended with a 128.73mph lap that took a mere 17 minutes and 35.139 seconds. Watch the onboard footage below and you’ll get an idea how narrow the road is.
“The road being so narrow is a problem because I am having to make a corner when the ‘bikes are going straight,” Higgins tells me. “There are a lot of slight corners which they can take straight. There are bumps for them that aren’t there for me and visa versa. Bray Hill is a good example: The ‘bikes are on the inside so miss the bump on the outside.” Higgins hit that exact bump on his 2011 attempt and nearly had one of the largest crashes any Subaru has faced (Colin McRae included). He had a passenger on board – who was so relaxed during the violent tank slapper that some questioned his sanity – and the extra weight increased the impact of the bump quite considerably. “I think the passenger had watched some rallying and thought that was going to happen on every corner,” Higgins adds. “He was disappointed for the next 36 miles.”
The Subaru recently finished third overall in the Festival of Speed timed shootout behind Justin Law in a Jaguar XJR12D and Jeremy Smith in an ex-Fittipaldi Penske PC22, but up until the last few runs, it looked like it might win the Shootout outright. While the 2-litre boxer engine is producing a whopping 570bhp and 800Nm of torque, the car is far from the perfect hillclimb machine. Based on a World Rally Championship tub – from one of the last Subaru rally cars, the car has been clothed in the most-recent model’s bodywork. It’s got a rear wing that Higgins can manually stall (adding 40mph) and it also has wider slicks on it.
However, the problem comes with the gearbox. The WRC cars are only geared to 125/130mph because every FIA stage is limited to 130kph. Engineers, unsurprisingly, then made the gearbox as small as possible around those reduced gears. All fine until you go to the TT with the car and want to hit speeds of 180mph. The only option was to fit a larger fourth, fifth and sixth gears which then meant Prodrive needed to totally change the characteristics of the engine. For the WRC it needed to have plenty of low-down power, but this car needed more at the top in order to bridge the gap between the long gears. It works well on the TT course, but not so well on the Goodwood Hillclimb.