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Concept corner: wide and loaded Group C GTSR?

6 November 2017



The owner of this month’s cover car, Rob Cooper, struggled to come up with a concept because, to use his own words, he’s already ticked off his car-ownership bucket list — but his wife hasn’t!

Rob Cooper’s wife, Lisa, is a patient lady — not only putting up with Rob but also putting up with his ever-changing cars. When asked to come up with a concept, he scratched his head until he eventually came up with something for her — although we’re guessing that it’s more just to allow him to build something else.

Owning the VK and a new GTSR, Rob’s plan for the ultimate ‘wife’s car’ is to combine the two — but not in a new-running-gear-into-old-shell type of way. Instead, Rob’d add the character of old to the convenience, handling, and drivability of new. Mind you, the way that HSV has built the GTSR, it’s a damn hard car to improve on. Being the man behind the successful Cooper Tyres New Zealand franchise, Rob is wheeling (get it?) and dealing with rims and rubber on a daily basis, so has access to the kind of wheels and tyres that many of us could only ever dream about. However, as a diehard Holden lover, Rob’s go-to rim of choice is the Simmons FR, as used on his VK.

As with the VK, he’d go big — real big, like 22 inches in diameter and a solid 11 inches wide up front matched with 22x13s on the rear. What’s that, they won’t fit under the guards? Well, they will the way Rob’s thinking — with the addition of a modernized Group C big-banger bodykit.
The square lines of the VK kit would give the modern rocket an almost robotic feel, one aided by the ducktail rear spoiler and a bit of clever treatment to the front end.

While painting the car in Formula Blue would suit Rob down to the ground, because the car would be for Lisa, he envisages it in a hot pink with black accents. It’s a hell of a plan for a late-model vehicle, but if there’s anyone crazy enough to pull it off, it would be Rob. 

Justin from LVVTA says: 
“The larger wheels that Rob has chosen are monsters; wheels that are 22×11 up front and 22×13 at the back would take up all of the wheel opening and then some. Often, large wheel fitments are facilitated by opening up the fenders for clearance, but, as the vehicle would be near new, it would be frontal-impact compliant, which would limit the modifications that could be done to any part of the vehicle that was designed to absorb energy during a collision. So, ultimately, Rob’d need to settle on a fitment that avoided any significant structural modification, especially in the front of the vehicle structure, and he’d also need to be careful around the rear openings. We suggest that Rob talk to an LVV certifier before committing to any cutting of the vehicle structure. 

“Other things to consider with a large wheel fitment where the wheel would extend outward — needing to be covered by a wheel flare — would be the LVVTA wheel offsets and the scrub radius, both of which can lead to overloading of suspension joints and reduced drivability and handling. Being a GTSR model, the brakes should already have more than enough stopping power to pull this up, but Rob needs to keep in mind that any wheel modifications would kick in the need for an LVVTA ‘cyclic fade-resistance test’, which puts the braking system through it’s paces, making sure that it’s still up to the task based on vehicle performance, vehicle weight, or change in wheel/tyre diameter that would increase the rotational load on the brakes.”


Your thoughts on last months concept Runnin’ on Empty concept:

Bruce Ainsley: “Um nah mate. Get rid of those overdone Cragers and chuck some steelies on it.”
Darren Tupuki: “Love a good lick of satin black. Reminds me of when you could pick up a Bel Air for a 50g pouch of Port Royal and half a dozen brown bombers. Those were the days.”
Ida Boyce: “Wouldn’t mind seeing that at Kumeu.”