We caught up with Andy Duffin from 3 Rotor Racing and his crazy Time Attack Spec 20B 3 Rotor Mazda RX7 at Round 1 of the Prowear New Zealand Superlap Series. This was his first outing in over two months since WTAC in Sydney.
Back on home soil, a fresh season, and on a track he’s more familiar with, he was amping to get out and lay down some fast laps. Despite using tyres he pulled out of the bin at WTAC after one of the Japanese teams threw them out, he still managed to set some decent times on the Saturday.
Sunday came around and with some slightly stickier tyres Andy was ready to do some fast laps! He managed a respectable lap time in the top 10 shoot out that secured him 2nd place overall. There was a lot of room for improvement though, in the way of using some brand new tyres. A bit more grunt, some new shoes and this thing was even more insane than it had already proven to be. Andy says the car is excellent to drive!
Now, lets take a closer look at the car and what makes it perform and handle so well!
There isn’t much to look at in the engine bay, but under all the carbon fibre ducting is a Naturally Aspirated, Peripheral Ported 20B 3 Rotor built by Green Brothers Racing. Pumping out a very impressive 515hp at the wheels, and approximately 650hp when the Nitrous is hooked up!!
With big power figures like this in such a light vehicle, stopping power very important. In the front is a full Endless 4 pot brake kit, and in the rear the factory Mazda calipers are still being used, but with upgraded AP rotors.
Keeping the car on the track is helped out by Fortune Auto 3 way Dreadnought shocks, paired up with Advan 18×11″ wheels wrapped in Yokohama Advan A050 295/35 R18 Semi-Slick tyres. This combination makes the RX7 savage through the corners!
The other key factor into keeping grip levels at maximum is the big aero package supplied by Kinetic Sim. The body is all made of composite materials, apart from the roof. The windows are no longer factory either, they are now polycarbonate made by Sandbrook Rennenglass.
Keeping Andy safe is a Racetech bucket seat and 6 point harness, along with an 8 point roll cage that connects to the front and rear strut towers. This also helps a great deal with the rigidity of the car.
The dash has been modified and lightened. Built from carbon fibre with a custom panel to house the MoTeC digital dash, and tucked away is the Link G4+ Thunder ECU. The Sportline steering wheel is wrapped in suede and is also light weight to help with precision turning.
You might be thinking to yourself, why is the AdrenalineR muffler set so far out the rear of the car? If you aren’t very familiar with this car, you will notice that it shoots massive flames all the time. Andy doesn’t want the rear bumper to melt!
The driveline on the RX7 is perfectly suited for the type of race car this is. A TTI 6 speed sequential dog box and twin plate clutch, feeding power to the Mazdaspeed LSD via a carbon driveshaft makes sure no time is lost while shifting gears.
This is by far one of the most extreme racing cars in New Zealand. Its one you really need to hear for yourself in person to appreciate the sound of the 3 Rotor revving to 10,000rpm. If you ever do get the chance to, make sure to check it out!
Car: 1995 Mazda FD3S RX-7
Engine: Naturally Aspirated 20B 3 Rotor
ECU: Link G4+ Thunder
Diff: Mazdaspeed LSD and carbon driveshaft
Transmission: TTI 6 speed sequential dog box with a twin plate clutch
Brakes: Endless 4 pot brake kit in the front, factory Mazda rear brake calipers over AP rotors
Suspension: Fortune Auto 3 way Dreadnough Coilovers
Interior: 8 point roll cage that links to the strut towers, Racetech bucket seats, Racetech 6 point harnesses, carbon fibre dash, MoTeC digital dash, Sportline steering wheel
Exterior: Composite body except for the roof, Aero package by Kinetic Sim, polycarbonate windows by Sandbrook Rennenglass, Advan 18×11 wheels, Yokohama Advan A050 295/35 R18 Semi-Slick
Power: 515hp atw, approx 650hp with nitrous atw