With such an astonishing variety of cars present at the 2016 instalment of the Leadfoot Festival, it was always going to be a tricky proposition selecting a couple for spotlights.
This was until the crisp twang of a ported rotary pulling as many revs as it could muster pierced the brief moment of still air between runs. Emerging hard on the brakes while setting up for the tight hairpin corner ahead was Aidan Barrett’s immaculately prepared, Group C inspired SA22C Mazda RX-7.
I had seen this car before, however at first glance I didn’t recognise the RX-7 wearing its clean new livery treatment. Previously the Mazda sported a livery resembling that of Allan Moffat’s 1981 Australian Touring Car Championship contender, but recently the guys made the call to switch the car to a new look, partly because theirs wasn’t the only Moffat tribute circulating the tracks of New Zealand.
Regardless, the simple livery works as an effective fusion of period and contemporary design cues.
Aidan’s RX-7 sports all the right aero protrusions you’d expect from a car inspired by the factory Group C machines, themselves derived from the IMSA SA22Cs being campaigned at the same time in the US. The prominent rear spoiler is so typical of the era too.
Another constant to the Group C theme are the wide fibreglass arches draped across hand-grooved 265-section Dunlop slicks. In the suspension department there’s custom Bilstein adjustable coilovers and a full course of rose-jointed arms and links.
What’s a rotary from down under without Simmons wheels? Contrary to the show car style of 18-inch and above, Aidan’s RX-7 is shod with 15-inch FR15 variants with widths of 9.5-inches at all four corners. Lurking behind the classic 5-spoke design are vented rotors gripped by 4-pot Wilwood calipers.
The fibreglass treatment doesn’t merely stop at the flared arches and spoiler combination, and in an effort to keep mass right down the Barrett’s have employed lightweight replacements for the doors, guards and the bonnet. Polycarbonate windows also contribute to a low kerb weight of around 940kg.
Spinning beneath the characteristically long nose of the Series 1 RX-7 is none other than a ported NA 13B rotary. In the Group C days, this was a controversial upgrade for the originally 12A-powered Moffat car, but nowadays it’s an almost default choice, based on the extra power, torque and parts availability versus the smaller rotary engine.
Built by renowned Kiwi rotary specialists Green Brothers Racing, Aidan’s 13B outputs 330hp thanks to peripheral porting and IDA-style throttle body injection controlled by a Link Fury engine management system.
The clean theme extends to the interior, which has also been stripped right back in the pursuit of weight saving. The original dash shell is retained, devoid of factory instrumentation and instead fitted with a simple pair of warning lamps and a couple of auxiliary gauges to monitor the essentials. Tactile items include a suede Sportline wheel and a beautifully machined billet alloy shifter to swap the cogs of the custom H-pattern 6-speed gearbox.
Finished in time for the Leadfoot Festival mere hours before the first car left the start line, Aidan managed to squeeze a 55-second run out of the RX-7 – a favourable result given the limited seat time with the new setup. With more seat time the car should pick up a few tenths or more, but for now the sights are set on a campaign on the circuits of New Zealand, perhaps taking on some of established competitors of the ‘all-comers’ GTRNZ championship.