THE V8-powered S5000 open-wheelers are running in a restricted form at this weekend’s Repco Bathurst 1000 on the grounds of safety.
Following lengthy discussions with the FIA and Motorsport Australia, organisers moved to trim 90bhp out of the regularly 560bhp Ford Coyote V8 engines.
The restriction has been made electronically; each engine remapped at the circuit on Monday to restrict the maximum throttle percentage when above 6,000rpm.
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That means the engines still accelerate hard out of corners but lack the top speed they would have otherwise enjoyed.
Garry Rogers Motorsport director Barry Rogers, whose team built the full fleet of cars, explained to V8 Sleuth that the change has been made to fit FIA regulations.
“The basic rule is that at an FIA Grade 3 circuit like Bathurst, for every horsepower you have to have 2kgs of weight, so we’ve had to drop 90bhp,” Rogers said.
“It’s a bit of a shame in the fact that the danger is really across the top of the Mountain, and you’re not really on full throttle there anyway…”
Spanish import Roberto Merhi topped Practice 1 this morning with a 2m04.0345s lap, set moments before a crash at Reid Park ended his day.
Practice 2 was then led by Joey Mawson, who lowered the benchmark to a still scintillating 2m00.8702s, with more speed likely as the track improves through the week.
The cars are believed to be doing in excess of 280km/h on Conrod Straight. They would likely have broken 300km/h, and run several seconds faster, in unrestricted form.
“Everyone likes to look at a lap time and everyone likes to measure against Supercars,” added Rogers.
“They were five seconds quicker than a Supercar at Sydney Motorsport Park, so if you worked on the same thing they should be eight or nine seconds faster here.
“But to be honest, Motorsport Australia worked hand-in-hand with us to get the cars here.
“We are thankful that we could race them here. Bathurst is the place to race so it’s good to be here and they’ll still be exciting to see.”
Listen to the V8 Sleuth team wrap all the Tuesday action from trackside at Mount Panorama in the player below!
Although Rogers says the discussions about the Bathurst requirements had been going on “in the background for about six months”, teams only learned of the change once at the circuit.
“It was only finalised around mid last week, and until we knew exactly what had to be done, we didn’t really want to discuss it,” said Rogers.
“People see it as a negative and we didn’t want the teams to be feeling negative before they got here.
“It wasn’t holding information back for any reason, other than wanting to know how it was going to be managed either with a restrictor plate or with the map.”