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Too fast? 327km/h+ Bathurst Skyline’s speed secrets

JUST over 30 years after the R32 Nissan Skyline bowed out of the Bathurst 1000 in controversial circumstances, a new legend was created at Mount Panorama.

Brad Sherriff’s R32 Skyline didn’t win a race in the Combined Sedans category at the Bathurst 12 Hour. And he didn’t call those watching a pack of arseholes.

But the incredible straightline speed of the Skyline Sports Sedan stunned fans trackside, went viral online and rang alarm bells at Motorsport Australia.

So, who is Brad Sherriff? What on earth makes his Skyline so quick? And will it ever race again?

Let’s try and answer those question one at a time.

A 49-year-old car tuner from Launceston, Sherriff is already well known in the Tasmanian motorsport and performance car scene.

He runs tuning house Racetech Performance, has campaigned his Skyline locally for over 10 years and worked on countless customer cars for both the road and the track.

The latter has included Murray Coote’s Time Attack weapon ‘MCA Hammerhead’, driven by the likes of Shane van Gisbergen, Tim Slade and Andre Heimgartner.

Sherriff speaks of those drivers with enormous respect. Whatever you do though, don’t call him a racing driver. He prefers the term ‘wood duck’.

“My mum wouldn’t let me push the pram until I was 25. I hadn’t done any driving and I still haven’t done much driving,” Sherriff tells V8 Sleuth.

“I don’t look at myself as someone who can drive. I’ve made an okay living tuning and engineering things and the driving has just been ‘who have we got that we can put in it’.”

Although understating his skill and daring behind the wheel, Sherriff is more forthcoming about his love of R32 Nissan Skylines.

“I worked on the cars when they first came out and I was just a kid,” he says. “Ross Ambrose had a GT-R and I drove it as a second-year apprentice. I don’t think I stopped smiling for a week.”

Incidentally, that silver Skyline was the very one in which a young Marcos Ambrose undertook his first car race at Baskerville in 1995 to gain a national racing licence.

Fast-forward to today and Sherriff insists his own R32 – a rear-wheel-drive GTS-T running to Sports Sedan rules – is nothing special.

After all, it’s a floorpan car (maintaining the original Skyline floor and most of its geometry), racing against purpose-built spaceframe machines with bodywork simply draped over the top.

While it gives away plenty in weight and stiffness compared to many Sports Sedans, what it does have is horses under the bonnet. As many as 1380 of them, depending on the engine’s state of tune.

Humble beginnings

One of countless R32 Skylines to arrive in Australia as a grey import, this now famous car’s racing life began in the early 2000s with a customer of Sherriff in Tasmania, Bill Fulton.

Fitted with a roll-cage by Jason White, Fulton raced it in local ‘Targa Class’ competition – a category introduced to accommodate Targa Tasmania competitors in circuit racing.

The class evolved into what is now Sports GT.

“It started as a standard, 2-litre, Jap import with 15-inch wheels, tiny little brakes and an aftermarket turbo on it,” says Sherriff. “I joke with Bill that he spent $350,000 on it over the years he had it.

“The wheels become bigger so the brakes could become bigger, and over and over again. It had six brake upgrades and I’d sold most of them to him and most of the wheels and tyres too.

“The gearbox went from an RB20 to a 25, that failed and it got a turbo 3-litre box, then a Holinger. It had so many birthdays it was ridiculous.”

The Skyline pictured in 2022. Pic: MJB Photography

When Fulton put the car up for sale in 2010, Sherriff made a phone call.

“I asked how much he wanted for it, and he said, ‘how much of the car do you want?’,” recalls Sherriff. “I said ‘how much for all of it?’. I think he wanted $65,000.

“I said, ‘I’m think I’m going to turn it into a rally car, how about I just buy the shell?’. I paid him $12,500 for the shell and then rang up a week later and asked him how much for the gearbox.

“Over a period of three weeks I accumulated everything that he’d unbolted and took off to sell separately! It was mad.”

Faster and faster

Sherriff began racing the Skyline in Sports GT and step-by-step introduced more and more power. A self-confessed RB26 engine novice at the start, he learnt plenty of lessons along the way.

“I dicked about with it. There were lots of issues with the car that needed to be sorted,” he says. “I ran a tune shop, but unfortunately the track and the road were slightly different.

“It took 12 months to work out how to keep the contents of the sump in the bottom of the engine and not on the window.

“The first time I ran it, it had 400kW (540bhp). It had a 2.5-litre engine and it made less than a step-through electric Vespa until about 6,000rpm. After that it was a vertical line to 400(kW).

“It was the worst thing I’d ever driven. You’d swear you were parked at a bus stop and somebody drove a B-double up your arse at 120 kays when it took off. It was terrible.”

Not satisfied with simply improving the engine’s reliability and driveability, Sherriff went bigger, all the while still running on a radial tyre under Sports GT rules.

“I developed a 500kW (670bhp) package, which was super reliable and got us the Sports GT title,” he says. “But I needed more, so we went to 600kW (800bhp).

“That’s power at the wheels too, not the hubs. The losses were about 25 percent at that point. It took another 12 months to get that engine to a point where it was reliable.”

Although reliable on track, Sherriff had reached the limits of Nissan’s cast engine blocks and the 600kW package required regular disassembly to deck the top of the block.

Turning off the traction control makes for spectacular results. Pic: MJB Photography

“I tune a lot of cast blocks that are 1000 horsepower, but they only go to the kebab shop,” he says of customer road car work.

“A bloke goes out to get a box of green tea with his 1000 horsepower car and says it’s killer. Yeah mate, try holding it flatout for a lap of a racetrack.

“I guarantee there will be shit flying over the roof and it’ll include your wallet!

“My background has always been to run something, optimise it, make it reliable and wind it back 10 percent. Then I can sell it to someone else.

“The 500kW version was very reliable. The 600kW version was a package where we could get to a lot of local kebab shops and maybe one on another island, but it wouldn’t last forever.”

The solution was swapping cast for billet. Machined down from a single piece of billet aluminium, the billet blocks remove many of the weaknesses of mass production, cast iron units.  

“The billet blocks started to appear, we were tuning Time Attack cars, and I thought ‘this is a really good solution if we can keep the temperatures under control’,” Sherriff says.

“So, we assembled an engine and ran it at 650kW (870bhp). We pulled it apart and everything still looked brand new.”

Sherriff’s blocks are made by South Australian company Bullet Racing Engineering and matched with a RB25 ‘Neo’ cylinder head, preferred over the GT-R version due to its combustion chamber shape.

The introduction of the billet block was followed by a series of bigger Precision turbochargers, pushing the output to 1380bhp. Sherriff and the car needed a new challenge.

Firing out of the hairpin at Symmons Plains. Pic: MJB Photography

“The radial tyre was always sketchy and the speed of the car meant it was time to move up to the next class,” he continues.

“Sports Sedans had just changed their rules to say you can have paddle-shift and billet blocks.

“Like all the blocks, the crankshaft centreline must remain the same, so you’ve got to be able to fit a standard rod, standard crank, standard pistons, and bolt the head on it, but it doesn’t have to work.

“Running in Sports Sedans (from 2021) meant we could put a bigger tyre on it. Eventually we found the biggest tyre we could and engineered the rear-end to fit.

“Since then, we developed what I call my 1800 horsepower engine, which is what’s in our cars (Sherriff’s own and that of customer Liam Hooper).

“But we only run them tapped at 1380, where they are very reliable.”

That power is transmitted through a Tilton clutch, paddle-shift operated Holinger RD6 gearbox and nine-inch differential developed in partnership between Sherriff and Holinger.

Brembo monoblocks provide the stopping power, while six-way, solid piston MCA dampers keep all four corners of the approximately 1400kg car on the road… most of the time.

Running down records

Before Sherriff set his sights on Bathurst, he ticked a couple of major boxes in his home state of Tasmania, taking closed car lap records at both Baskerville and Symmons Plains.

The Baskerville record was a particularly significant achievement, considering the previous benchmark at the tiny 2km venue had been set by Alan Jones aboard a Porsche 935 in 1982.

The Alan Jones Porsche 935, pictured at Sandown in 1982. Pic: an1images.com / Marshall Hornby

“I really wanted to beat Alan Jones’ long-standing lap record,” says Sherriff, who after multiple attempts set a new benchmark of 51.4048s in October of 2022.

“That car had 14-inch wide wheels on it, it was reported to be 750 horsepower and 880kg, driven by the bloke with the biggest balls and the most talent arguably that ever came out of Australia.

“Baskerville is an awesome track, but it’s like a goat track, and everyone said to me when I bought the car that I’d race it at Symmons but never go to Baskerville.

“I really wanted to prove the point that a heap of shit with a good engine and the cupholders pushed in was capable of doing a time there that no one had done in 40 years.

“Then obviously at Symmons we’ve lowered the lap record every time we’ve run the car.”

Sherriff’s current Symmons Plains lap record stands at 50.6025s, set last November. That’s over six tenths quicker than the Supercars record and, according to Sherriff, included touching 300km/h.

VIDEO: Baskerville lap record onboard

Climbing the Mountain

While the Baskerville record was a major milestone, Bathurst loomed as Sherriff’s ‘holy grail’.

“My dad was a motor mechanic and every year we’d sit down and watch Bathurst,” he says. “I decided as a kid I really wanted to go there.”

In preparation for February’s Combined Sedan races at the Bathurst 12 Hour, Sherriff tackled Challenge Bathurst last November with customer Hooper and his near-identical car.

“I thought it’d be a good idea to find out which way the track goes,” Sherriff says of going to Challenge Bathurst, run as a series of sprint sessions.

“Watching on TV is great, but I don’t think it gives you any perception of driving the place at speed. So, I decided we’d get an international ticket and go to Australia and have a little look.”

Hooper also tackled the final round of the 2022 Australian Sports Sedan Series at Sandown earlier in the month, giving the field an early taste of the Racetech package with a competitive showing.

Sherriff’s track time at Challenge Bathurst though was limited to just seven laps as he shared the car with Hooper and made various changes.

Liam Hooper’s Skyline at Challenge Bathurst. Pic: ChallengeBathurstPhotos.com

The crest on Mountain Straight, which is more pronounced than those on Conrod, caused two problems.

The vertical g-force meant a sudden drop in oil pressure. That was quickly resolved at the track, but a second issue became post-event homework.

“I came away from Bathurst going ‘the front end is the sketchiest thing I’ve driven in my whole life’,” Sherriff admits. “It was beyond horrifying.

“Up Mountain Straight, I was lifting to 50 or 60 percent throttle and the front of the car was off the ground for about 120 metres.

“A young guy came up with his dad. He said to me ‘mister, your front wheels are off the ground’. I said, ‘really, for how far?’. He held his hands out to about four inches.

“I said really? His dad goes ‘yeah, they are’. And I said, ‘it feels like double that to me!’.

“I was rolling out of the throttle to keep the car from going up… I said to Liam we’ve got to do something here with aero because this is bad.”

VIDEO: Front wheels off the deck on Mountain Straight

Sherriff worked with ex-Formula 1 aerodynamicist Sammy Diasinos (Dynamic Aero Solutions) and Sydney Composites to have a front diffuser made before the return to Bathurst in February.

“They said you have to promise us that you’re still going to lift (at the hump on Mountain Straight),” Sherriff says.

“Sammy had done some analysis with the track fallaway as you go over the hump and said if you hold it flat it’ll still go upside-down.

“I said I’ll try it and let you know! And I did. It’s now manageable to the point where the wheels are just off the ground. It was only about 25mm off and not for 120 metres.

“I don’t mind the wheels off the ground as long as I don’t have to turn and that I can see more track than sky. I thought that bit was more than achievable.

“Liam still wasn’t comfortable, he said ‘it doesn’t feel nice over there’.

“I said, ‘you’re not eating a cake dude, it’s never going to be nice, just bloody send it and trust me, you’re not doing more than 298 up there, you will not fly’.

“So that was a huge gain.”

Aero changes helped keep the car on the ground at the 12 Hour. Pic: MJB Photography

Turning heads

Sherriff’s run at the Bathurst 12 Hour is now stuff of legend. He didn’t actually win any of the three Combined Sedans races, but he sure turned heads.

Because of the varying speeds of the cars in the category, a 2:09.0s minimum lap time was in place. Sherriff scored pole with 2:09.1732s.

The Skyline clashed with MARC II V8 driver Geoff Taunton in the opening race and later retired with a misfire, before charging from 38th on the grid to second at the flag in Race 2.

Sherriff was demoted to third as a penalty for accidentally breaking the 2:09s barrier (2:08.8s) and then crashed out of Race 3 at Reid Park while leading Taunton.

“The cars are still very, very ordinary over the top, but how good can a floorpan car be?” Sherriff opines. “Once you’re up there you’re just floating it around.

“The aero is not working as effectively as it should because you can’t put enough spring rate into it. More spring just gets gobbled up in the chassis and we don’t get the change at the wheel.  

“That’s why nobody with half a brain mucks around with a floorpan car in a class that allows you to go to a full (spaceframe) chassis!

“I’m in a position where I’ve got a 1400kg car and it’s being operated by a ‘wood duck’, so I can’t expect the thing to be a MARC car because it’s never going to be. They are beautiful cars.”

MARC cars lead off the grid, but Sherriff soon blasted to the front. Pic: Ross Gibb

The big talking point though of course was not the battles with Taunton or the lap time, but the Skyline’s straightline speed, including the incredible numbers produced on Conrod Straight.

Sherriff posted an onboard video on social media after Challenge Bathurst in which the speed readout was covered once it hit 280km/h on Conrod. But at the 12 Hour it was there for all to see.

Official timing had the car at 327km/h. That was easily 30km/h up on its nearest rival and believed to be the fastest speed ever recorded on Conrod Straight.

Sherriff though indicates the actual peak number, achieved between the position of the speed trap and the braking point for the Chase, was 338km/h.  

“I was trying to do the right thing. We ran it at 1040 horsepower at Bathurst (down from 1380bhp), so it’s quite a soft tune-up for what the engines will turn,” says Sherriff.

“I really did want to properly send it, but I knew if it had a 50 on the end of the 3 number (350km/h) it was going to be a full drama!”

VIDEO: Full onboard lap from Challenge Bathurst

Boost control

According to Sherriff, the car ran with no more than 32 pounds of turbo boost pressure at Bathurst, far below its maximum potential.

Sherriff though says the key to making it driveable is the engine management software, called GPRP-Pro, which he developed alongside MoTec for its M150 ECU.

“In our GPRP-Pro package, boost becomes an academic number,” he says of the firmware, which includes a sophisticated traction control system.

“It’s torque mapped. I’ve got a knob on the dash and you request how much torque you want.

“When I request 800 Nm, it’s calculating the engine power and torque that it’s making and will limit the boost to the minimum boost required to make that amount of torque (at any given RPM), and obviously torque multiplied by RPM dictates the power number.

“That enables us to have a very, very linear throttle opening,

“Most turbo cars if you open up full throttle at the apex, which you have to do generate airflow to get it to boost, by the time you’re at the exit it’s got way too much power and you have to come all the way back on the throttle plate to 40-45 percent to control the amount of wheelspin.

“With our Pro package, when I’m going down Conrod at 338km/h, the actual throttle is open 68 percent. I’m 100 percent pedal, but the throttle plate is only open 68 percent. What that means is if I lift my throttle pedal back by five percent, I get a five percent power reduction.

“Now in any other (turbo) car with any other ECU package, if you’re at 100 percent pedal and you had 100 percent throttle opening, you’d have to come all the way back to 65 percent pedal before the power then started to drop off.

“That refinement is where a lot of the speed of these cars has come from. It might be 1000 horsepower, but you have 1000 horsepower at 100 percent throttle and 500 horsepower at 50 percent throttle. It’s not a digital switch.”

VIDEO: Sherriff explains torque mapping

To emphasise his point about the usability of the engine’s performance, Sherriff adds a startling footnote.

“It’s a beautiful thing in the rain,” he says. “You wind it (the requested torque number) down and it’s like driving an AU Falcon, but you can progressively just add engine.

“I was really hoping the whole weekend rained because on a Michelin P2L it’s the most amazing thing you can drive.”

Meanwhile, there’s the obvious question of what lap time the car could do without the 2:09.0s benchmark in place. Based on the weekend, Sherriff feels he could do 2:05s.

“That’s just with me driving,” he says. “If you put any A-grade driver in it, if they’re not four seconds a lap faster than a ‘wood duck’ up there I’ll go to the pictures.

“Keep in mind there’s still 400 horsepower to chuck at it as well. A good guy with an engine wound to it, the number would have a 5 in front of it (under 2-minutes).”

Sherriff exits the Chase at Bathurst. Pic: MJB Photography

Shooting at the Sherriff

As impressive as Sherriff’s Bathurst blast was, it’s no surprise that such high speeds drew concerned looks from Motorsport Australia.

A representative of the governing body called Sherriff on the Monday after Bathurst to discuss the situation, while a public MA statement confirmed it was looking into Sports Sedan eligibility rules.  

Sherriff responded with a diplomatic but firm post on his Racetech social media channels, declaring he’d no longer run the car if its performance was restricted.

The situation has triggered a flurry of conversation around FIA track gradings, power to weight ratios and maximum speeds, as well as the Sports Sedan category’s treatment of turbocharged engines.

Asked directly if his car is dangerous in its current form, Sherriff says: “I look down and I’ve got a pair of black things on with laces and as I pull my legs up and down, they move.

“I look at my hands, I’ve got 10 fingers, I’ve got two eyes, two ears… everything still works and I’ve driven that car for a very long time.

“The crash I had at Bathurst had nothing to do with a safety problem, that was me catching a glimpse of a Mustang coming up behind and pinning my eye to the mirror.”

The racing future of the car is uncertain. Pic: Ross Gibb

For now, the Skyline is undergoing repairs following its incident at Bathurst, having escaped with relatively minor damage.

Sherriff plans on contesting the Australian Sports Sedan Series with the car, which includes a round at Mount Panorama as a support to the Bathurst 1000 in October.

Whether the Skyline races again though will depend on Motorsport Australia’s next move.

“I’ll repair it as if I’m running, but we’ll wait and see,” he says. “That car will never ever be seen again while I own it if its performance is restricted (by rule changes).

“Every time I get it ready to go, I think ‘do I really want to run this?’, because you could just sit there and admire it.

“(The R32 model Skyline) is one of those cars that excites me just to look at. It always has.”

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