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UNDER THE SKIN

OL’ FAITHFUL The Whiteline Racing Chevrolet Camaro has been a mainstay of the Touring Car Masters field for nearly 10 years, first in the hands of Andrew Miedecke and now with Sydneybased engine components distributor Adam Bressington. Auto Action took a look under the skin of the brutish yellow Camaro, which has been a constant thorn in the side of both John Bowe and Steven Johnson at the front of the Touring Car Masters field

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Words: HEATH

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Images: INSYDE

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N ITS 10-year history, the development of Touring Car Masters has been rapid as the class has moved away significantly from its amateur Group N roots to become a semi-professional category featuring names like John Bowe, Steven Johnson and Jim Richards.

The level of car preparation and development has also lifted as demonstrated by the recent additions of Andrew Fisher’s Ford Falcon GT, Jason Gomersall’s Holden Torana A9X, Marcus Zukanovic’s Ford Falcon XD and Mark King’s newer-shape Chevrolet Camaro RS, all of which have made use of the continued freedoms allowed under updated rules.

However one driver, Adam Bressington is bucking the trend. His 1969 Chevrolet Camaro SS has continued to be a highly competive car that has not upgraded to some of the more recent freedoms and yet after nearly 10 seasons continues to be as competitive as ever.

Bressington has been driving the car for two years now, taking over from former open-wheel and touring car driver Andrew Miedecke, who had garnered strong results during his time behind the wheel. Bressington had had a disastrous year in a Holden Monaro owned

by Jim Morton in 2013 and entered rounds sporadically, until Bob Middleton offered a drive in the Camaro at the Queensland Raceway round in 2016.

It was a strong round for Bressington, who then enjoyed another at Bathurst before Middleton suggested he should contest the series full time in 2017.

“I’ve always enjoyed the category,” Bressington told Auto Action.

“I had a great run at Bathurst [2016] where I was battling Bowe, Johnson, (Glenn) Seton and Kingy [teammate Mark King], then Bob suggested ‘we better do it next year’, so we did.”

Bressington has been a frontrunner over the past two seasons of TCM in what is one of the oldest cars in the field. He acknowledges that it may not be the fastest in a straight line or the lightest car in the field, but he explained the car is well balanced and a pleasure to drive.

“It is a nicely balanced car that has been engineered well.

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“It’s a special thing to drive and it’s good under brakes. It was really good in the wet at Bathurst, which is the first time I had run in the wet with newer tyres. I feel comfortable in the car despite not having the seat time I’d like. We don’t test, we do our testing during the practice sessions at a race meeting,” Bressington explains.

The guru behind Bressington’s Camaro is the experienced Mark Peacock, affectionately known as ‘Birdman’. Peacock has been preparing Middleton’s array of racing machinery for 30 years, detailing to Auto Action how far TCM has evolved in its short history.

“It evolved from Group N, but the cars are notoriously fragile because they are all productionbased and the life of those cars are getting so old now,” Peacock explained.

“The main issue was the reliability, so it has transformed into this, which basically are Group N cars with some modifications to make them more reliable and safer in the form of better brakes, better gearboxes, better diffs.

“It was just simply from a reliability point of view and it really started out as gentleman racing, but very quickly – within 2-3 years – it became a senior’s tour for retired racing drivers and it got pretty serious.

“We’ve had a fair bit of evolution in the 10-12 years it has been going, but we’ve got to the point where the availability of parts is a lot thinner in terms of panels, and with the engine rule changes, it has developed into a very serious category.

“Considering the differences between one of these and a Supercar, these have no tyres, no brakes and only four gears, yet they aren’t that much slower.”

This is mainly down to the engine. The 350 small block Chev motor is made almost entirely of aftermarket parts due to the limited supply and reliability of the originals. To keep up with the frontrunners, the engine is good for almost 700bhp, using a single four-barrel carburettor and utilising a dry sump.

“We have a reasonable amount of freedom in the engine, we have control cylinder heads, there are certain types approved for each engine and we’re not allowed to use much in the way of exotic material, so no titanium rods or cranks,” Peacock said.

“The engine side of it, now that it has gotten so serious, when we first started a 530hp engine was good enough, but now if you’re not pushing 700hp, you’re nowhere.”

When quizzed where the aftermarket parts are produced, Peacock explained that most of the parts are custom designed and built in Australia. He went onto explain further that originally he utilised American parts and modified them slightly to suit Australian racing conditions, but that local components have proven to be the equal of the imported parts.

“Most of those are custom and built

Although close to 10 years old, the Whiteline racing Camaro continues to be as competitive as ever in the hands of Bressington.

Whiteline Racing's Camaro is a consistent frontrunner and delivered Bressington the Pro Am title last year.

UNDER THE SKIN

1969 CHEVROLET

CAMARO SS ENGINE

350 small block Chevy, 23 degree heads, dry-sump, single four-barrel carburettor, CES custom exhaust system, Power: Approx 650bhp Max Revs: 7500rpm Transmission: Jerico 4-speed NASCAR dogbox Ford 9-inch differential Triple-plate clutch

INTERIOR

Cobra seat, Sparco seatbelts, fire extinguisher, built-in custom pedal box, Auto Meter gauges

SUSPENSION

F: King Springs coil overs, Penske shocks R:King Spring Mono leaf, Penske shocks Brakes: 4-piston Brembo calipers, 12” discs, Project Mu pads Wheels and Tyres: 15” x 8” performance Superlites, Hoosier racing tyres

DIMENSIONS

Length: 4724mm Width: 1880mm Height: 1298mm Wheelbase: 2743mm Weight: 1500kg

The 350 small block Chev in Bressington's Camaro generates awesome power but Peacock says it needs to: "When we first started a 530hp engine was good enough but if you're not pushing 700hp, now you're nowhere."

here,” Peacock told Auto Action.

“I imported American exhaust systems and modified them because the problem was that ground clearance became a big issue. Because we were running so close to the ground the standard exhaust systems don’t last very long, so what I did was buy off the shelf competition designed systems, then modified them to fit them in the available space.

“With our latest spec engines, we decided to go with a system that was designed in Queensland by CES (Competition Exhaust Services), that do a lot of work with some Supercars teams. The team at CES completed all of the design work, then a local company in Adelaide did all the fabrication. It’s quite a complex undertaking because there are space restrictions in the car such as steering boxes, wishbones and all the other engine components, which makes it a really tricky job and on average takes two weeks to finish.

“It’s not cheap.”

But there is reason behind the madness is that critical power gains can be made through the exhaust system, which is ideal for the Chev small block, which according to Peacock has a number of deficiencies compared to the rival Ford engine.

“Running a Chevy, you’re a little bit behind the eightball compared with the Ford. It’s a lot easier to get the horsepower and torque out of the six-litre Ford engine than it is out of a Chev,” Peacock continued.

“Whatever little bit we can find in the exhaust through fabrication and design, we get a little bit more mid-range torque, ultimately it all counts. You get to the point where you’re spending lots of money for very small improvements.”

Cooling is also another important feature of a car the age of the Camaro. An American Afco radiator was chosen by Peacock as it fitted in the tight confines of the engine bay and provided adequate cooling to keep the engine running at top performance.

Much like the ‘70s, oil cooling is still an issue now, but Whiteline Racing has experimented and successfully found a solution to the problem despite coming at a cost.

“One of the biggest issues we have is oil cooling.

There are two ways you can go, a smaller oil cooler in front of the radiator, then you compromise your water cooling and run the risk of getting small punctures in the oil cooler. Or what we have chosen to do, which is run the oil cooler behind the water radiator which means it has to be a lot bigger and is a little bit expensive than normal.”

TCM regulations dictate that all cars must use a 4-speed gearbox, which mean the majority of teams look to the US and NASCAR for a strong and reliable unit. Whiteline Racing use a 4-speed Jerico NASCAR

Brakes are a major consideration on the Camaro due to the need to stop the 1500kg monster at fast tracks like Bathurst and Sandown.

gearbox in the Camaro, based on the Super T10 or Ford Toploader, but enhanced for racing.

“Virtually everyone uses NASCAR-style four-speed gearboxes, it’s a dogbox primarily designed mostly in America, although I’m now having some gears made locally.

It’s a proper racing gearbox and that’s always been the case from the beginning, because it was one of the big issues with the Group N cars. The production four-speed gearboxes weren’t up to the punishment.”

When it comes to the diff, Whiteline Racing has gone either way with a Ford nine-inch (which features in this car) and a Chev 12-bolt fitted in the other team car. Both have advantages and disadvantages in terms of ratio availability and power loss, which Peacock said evens itself out over the two choices. “[The 12-bolt] is certainly strong enough, but the ratio availability isn’t quite as good as the nine-inch, but the other side of the coin is it is a more efficient diff with less power loss through the driveline. Because there are very few power losses through the transmission, the main loss of power is through the diff and the Ford diff consumes a bit of power as the primary design was to be quiet for road use.

“The trade-off there is that all of the componentry is ready to go with the aftermarket stuff and almost an infinite number of ratios. But the down side of it is that it tends to run at higher temperatures, which means that you have to stay on top of oil lubrication and make sure that your set ups are right, because if you get it wrong, it turns to shit pretty quick.”

Further development of the TCM regulations allow carbon clutches to be installed but when the category moved away from standing starts, the clutch ceased to be a weakness, so Whiteline Racing decided to stick with an off-the-shelf triple plate clutch, which is "nothing particularly exotic" according to Peacock.

Having King within the Whiteline team has been useful in regards to suspension tuning, as shock absorber development has proven to be an area where big gains have been made. This has allowed the team to make minimal changes from track-to-track, which was aided by the category moving away from incorporating a production-style spring and allowing full coil-overs to be utilised.

“Originally, we had to use the production-style of springs, 5-inch diameter things, it was all free other than that. Now we’re allowed to use a full coil-over in the car, so that means we can use a much smaller spring than the shock absorber,” Peacock said.

“Where we spend all our time and effort is shock development, which has been mainly completed at King Springs. It’s a whole world unto itself and to do it properly you have to have access to the shock dyno, experiment a bit, be conservative or be 95 per cent, so you can push the envelope a bit. It’s one area that we spend a lot of time and effort in development because with any one brand of shock, there is often a choice of half a dozen different style pistons, which produce different curve characteristics and combinations of such.

“Some of the technology we use is stuff that’s been

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developed in the states for NASCAR, some of it is our own doing.”

The shocks chosen by Whiteline Racing are Penskes and King Springs supply the front coil overs and mono leaf springs on the rear.

Brakes are a big issue for the behemoth Camaro as regulations dictate 4-piston calipers all round and a less than ideal diameter size that stops a car weighing 1500kg. The goal for Peacock was to make sure the car stopped as well at the end of the race as it did at the start, and for that he has chosen Brembo calipers, Project Mu pads from a Supercar and American sourced 12” discs that are machined to size, a choice that is made based on cost.

The Camaro bodyshell was originally sourced from the US and came complete with bullet holes!

Once it arrived at Whiteline Racing’s workshop it was sent to be soda-blasted, removing all the paint and cleaning the bodyshell. Once soda-blasted the process of repairing and reinforcing the bodyshell got underway, removing unrequired items such as handbrake cable brackets and battery carriers, before a cage was installed, which Peacock farmed out.

“There are a couple of ways you can go about it. You can build an FIA specified design with approved material and we farmed that out because there are builders who have CAMS accreditation to do that,” Peacock said.

“You can theoretically do it yourself, but when there is an inspection process, it is fairly complex especially if you’re not in Melbourne. The roll cage design is relative to the car, but primarily it is a full cage similar to what Supercars were

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running 5 or 8 years ago. You can go chrome moly, but that involves a rather complicated inspection and design process that gets very expensive, so we chose to just go down the expanded approved design route, which is cheaper and quicker. The difference in weight is not hugely significant, it is probably 20-30 pounds over the whole car.”

Dummy assembly was the next step to take place before the bodyshell was sent to the paintshop before final assembly completed, or as Peacock put it, ‘finding all the little things missed’.

Electronics are starting to creep into TCM, with partial MoTec systems being utilised in some of the newer racers, however wheel sensors are banned, leaving only a limited amount of data that can be utilised by teams and drivers.

“We’re very limited with electronics, we’re now able to use some data acquisition and digital dashboards, not that we run them as when I originally built the car it had to be all analogue gauges. Adam’s car has got a PDM unit, which is just a concession to reliability really,” Peacock expanded The rest of the interior is made of a Cobra seat and Sparco belts, which have a lifetime of around 10 years as TCM only complete short sprint races, Despite newer, younger competition, Bressington continues to be a fixture at the front of the TCM field in the yellow Camaro. Even though on the outside it looks straight from the race tracks of 1969, the venerable Camaro hides underneath its stylish body a mixture of NASCAR and Supercar technology, in what is becoming a very advanced class.

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