Published in NZ Performance Car Issue No. 194

Ten years ago, at the age of sixteen, Jason Treloar swapped a shitty old Mazda 626 for an even shittier 1980 Series 1 Mazda RX-7. “It was a wreck,” Jason admits. “It was pretty much just a primered shell on Hotwires that had been used as a skid hack down in Manurewa. I was only young and just wanted a rotary, so I grabbed it. Originally, it just started as a quick pull-apart and tidy up.” From those humble beginnings, Jason’s ‘quick tidy up’ has turned that same bucket-of-bolts Mazda into what has been judged the best first-generation RX-7 in the country, not once, but a total of five times over the last few years.

How does a quick project turn into a decade-long labour of love that shows no signs of abating? Jason explains: “Once you pull it all apart, you begin finding more and more stuff to do, it just snowballs. I spent nearly two years completing the original build, but that was just the start.” The original build, like everything done to the RX-7 over the last ten years, was carried out completely by Jason himself, who has a very hands-on approach. As he says, “When I was young, I couldn’t afford to take it anywhere to get work done, so I just tried to do it all myself, learning as I went.” All these years later, and it’s now Jason that does work for other people, having fabricated parts and built motors for many prominent rotaries.

The first build of the RX-7 saw a simple carbied 12A under the bonnet and its first appearance in the well known ‘Adriatic Blue’ paint. What surprises not only us, but Jason too, is that paint job still looks great today, even though by all accounts, it shouldn’t have even been too hot eight years ago when it was new. “I painted it myself when I was eighteen,” Jason explains. “I just did it in a shed and there was an ants’ nest directly above the car that died [we can only assume from the fumes] during the clear-coat process.” Suffice to say, a lot of time was spent with a razor blade and some very fine sandpaper removing the ant graveyard from the newly coloured bodywork.

Jason didn’t stop at bodywork when it came to improving his skills, and since those early days, the RX-7 has seen countless new motors built by the man himself. Interestingly however, while nearly everyone else was working with the bigger 13B, all of Jason’s motors have been little 12As in some form. “That was what this car originally had, and I’ve always wanted to stick with it. I like the 12A — it’s the little motor that could. I think they’re underrated, and there’s not many high-power 12As out there, so it’s different.” After trying all kinds of different set-ups, Jason has finally found the perfect 12A arrangement with his latest creation — a turbocharged 12A combo-port. The motor, which runs huge 50mm PP ports in the housings and stock ports in the side plates, has been a real success for him. He tells us, “This is definitely the best motor yet. It drives really well while still providing plenty of power — it’s been all the external stuff that’s proved the most challenging. The intake plenum and manifold, for example – I’ve had to remake it all three times to get it right. There’s not exactly a handbook when it comes to custom stuff like this.” Although still on a run-in tune pushing only 14psi through the Garrett turbo, the little 12A makes 240kW at the wheels, with no doubt much more to come once the car makes it back to the dyno. Considering Jason has already run an 11.2-second quarter-mile at 189kph on a previous engine, we can only assume that an entry into the NZPC 10-second club is not too far away.

Over the years, Jason has slowly upgraded this Mazda piece by piece (most of those pieces have come out of his own workshop, too), and it now resembles a great all-rounder. It’s got the show style that wins him plenty of accolades, which Jason says he garnered inspiration for from his various trips across the ditch to events like Jamboree, but it’s also got the grunt and the high-end build quality to make it an incredibly fun and reliable weapon both on and off the track. With the latest incarnation of the RX-7, Jason has come ever closer to his idea of the perfect rotary, even if there were a few cringe moments in the learning process. “I hate to think about all the things I’ve had to do over two, three or four times since I’ve had the car, but I guess that’s what the learning process is all about.”

We love the fact that this car has only ever had a 12A motor in it, that Jason has resisted a 13B for so long — especially as it’s not as though it would have been difficult for him to throw in a bigger motor. “I could install a 13B into this car tomorrow if I wanted to, I’ve got all the parts sitting around. But I won’t — I’ve got different plans.” Although he wouldn’t divulge too much information, we did catch mutterings of “18A” and “tubs” from Jason. Whatever the future holds for this RX-7, there’s three things you can be sure of: it will be 12A-based in some form, the work will be of exceptional quality and considering he’s already owned it for his entire adult life and has zero plans to give it up, no doubt it’ll be Jason Treloar that’s behind it all.

Tuning Menu

Engine: Mazda 12A 1200cc twin rotary
Block: Combo port (50mm PP plus factory ports) 12A plates and housings, lightened rotors, stud kit, window bearings, unbreakable apex seals, competition oil pump
Intake: Custom stainless steel intake manifold, custom alloy plenum, 80mm throttle body, 600x300x75mm intercooler
Turbo: Garrett TA45
Wastegate: Turbosmart 40mm Progate
Exhaust: Custom steam pipe manifold, three-inch stainless system, Adrenalin R resonator, custom rear muffler
Fuel: Carter lift pump, Bosch 044 main pump, SX regulator, 4x 1600cc secondary injectors, 2x 850cc primary injectors
Ignition: Bosch coils, NGK plugs, 9mm leads
ECU: Link G4RX
Cooling: Alloy radiator, factory oil cooler, electric water pump
Other: De-loomed engine bay, side-mounted alternator, welded and smoothed engine bay, 10mm stainless scatter shield

Gearbox: Toyota W55 five-speed
Clutch: Tilton twin-plate, 14-pound flywheel
Diff: Toyota Hilux LSD, enlarged driveshaft

Struts: Custom-made adjustable coilovers
Springs: Custom springs
Other: Full Nolathane bush kit
Brakes: (F) Series 6 calipers, Series 4 rotors, (R) Series 6 calipers and rotors

Wheels: (F) 17×8-inch Rays Engineering Lexion, (R) 17×9-inch Rays Engineering Lexion
Tyres: (F) 185/35R18 Nankang, (R) 205/40R18 Nankang

Paint: Adriatic Blue
Enhancements: OEM replacement light lenses front and rear

Seats: KW buckets, Jamex harnesses
Steering wheel: Momo
Instrumentation: Auto Meter gauges
Roll cage: Half cage
Other: Full white vinyl interior re-trim

Power: 240kW (320hp) at the wheels on 14psi (run-in)
Weight: 1000kg
0–400: 11.2@189kph

Driver profile

Jason Treloar 
Age: 26
Location: Auckland
Occupation: Refrigeration engineer
Length of ownership: 10 years
Build time: 10 years
Thanks: Laura for being so understanding and all my mates who have helped through the years — you know who you are

Words: Peter Kelly    
Photos: Adam Croy