2025 RX-8 Cup champion Stiaan Kriel takes us under the bonnet of this fast-growing one-make racing series.

Stiaan Kriel has claimed the 2025 RX-8 Cup series trophy. After a challenging start to the season thanks to his car being stuck on the other side of the country at the first round, the Dealer Principal of Sydney’s Alexandria Mazda showed a clean set of wheels in this year’s one-make battle, combining his driving skills, consistency and careful vehicle preparation to secure the overall prize in this rapidly-growing one-make series.

But as he points out in this interview, the RX-8 Cup isn’t about turning up at a racetrack, strapping into the driver’s seat and just driving. Nor is it about having the biggest chequebook.

Enjoy this behind-the-scenes interview that reveals why Australia’s RX-8 Cup has emerged as a destination for experienced competitors, first-time racers and even motorsport legends like John Bowe, all of them looking for the thrill, challenge and camaraderie that comes with racing a Mazda rotary legend.

It was surreal. It’s not every day you arrive in a new country, begin life in a busy city, start a new professional life running a Mazda dealership and start racing at unfamiliar circuits!

I’ve always taken the no-funding pathway with motorsport. I’ve always built, set up and worked on my own racing cars. That’s meant a lot of late nights, careful planning and long hours, especially with running the Mazda dealership. My wife and my three little rescue dogs go through a little bit of a sacrifice on the weeknights I work on the racing cars until eight or nine o'clock at night.

To win the 2025 RX-8 Cup in Australia at my first attempt feels pretty good. There have been some big highs and tough lows during the season but when you have one of the best car brands and its reliability on your side, it's pretty easy to do.

There were many. A highlight was racing the final round of the season with my wife. She also has a racing background. Dave Murphy, an RX-8 competitor, loaned us his spare car for the last race at Morgan Park. She came third in one of the races. It was her first time racing there and it was great to share the track with her and see both of our names on the time sheets.

The other highlight was at the first round of this season. I landed in Melbourne – my first time – on the Friday of the first race weekend and headed straight to the Phillip Island Grand Prix Circuit. I’d never been there before. I met everyone in the RX-8 fraternity for the first time. I had to rent the use of someone else’s RX-8 Cup car because mine wasn’t ready. I drove the track for the first time on the Saturday morning. On Lap 3 of qualifying – the only session I’d get to drive the circuit before the first race – I broke the lap record for the category. I drove into the pits and everyone asked, “Have you raced here before?” Other than racing in South Africa and New Zealand I was a total rookie in Australia. I even had P Plates on my RX-8 Cup Car that weekend because I’d only just secured my local racing licence.

A few races before the end of the season my car was disqualified for a tiny technical matter. It was the height of a bolt head that caused it. There was no performance advantage but it still cost me 30 championship points that weekend. Rules are rules in motorsport. Even McLaren felt that sting in this year’s F1 title race. 

I’ve secured sponsorship for 2026, which is exciting! And I’ll also get to run the number 1 on my car next season.  

I’ve also secured a second Mazda RX-8 Cup car. I’ll race this car to defend my title and my wife will race the red RX-8 I used during 2025.

I’m also considering moving up to another racing series, the V8 SuperUte Series. There’s an opportunity to buy a Mazda BT-50 that’s been converted to race in this series. These cars all run a standardised 6.2-litre V8 engine and six-speed manual gearbox. They’re a lot of fun and sound great.

Firstly, it’s fairly affordable. Motorsport can be expensive and the RX-8 Cup is a great way to go racing. You can buy a car from anywhere between $30,000 and $50,000 depending on condition and equipment. In motorsport terms that’s a great entry price.

Secondly, the racing is so close because the cars are similar in performance. The series’ rules make the cars as close to identical as possible. They are the same weight, they have controlled brake discs and brake pads, and the engines are standard. Nobody runs away from you on the straights but you can catch and pass people in the corners because the cars handle so well.

The cars are all well-regulated. For example, the officials will do spot checks on cars and their ECUs (engine control units) to ensure nobody has fiddled with their programming for better performance. ECUs are sometimes randomly swapped between cars without notice, which means a competitors’ car can’t get any performance advantages. The engines are sealed, the gearboxes are sealed, the diffs are sealed, the suspension is standard except for the control shock absorbers; the cars are so close in performance. You can set your car’s wheel alignment, ride height and shock settings – and that’s it.

Mazda’s reliability also plays a big role. Because the cars are so well built and durable they offer so much fun without vast amounts of technical maintenance. For example, I’ve seen an aftermarket wheel bearing last three races whereas a properly maintained Mazda Genuine wheel bearing will go for many years.

The RX-8 Cup has drivers of all ages and experience levels from across Australia.

Being a production car-based racing series it means the cars are very equal in performance, which is also helped by the strict technical regulations that govern the cars’ eligibility.

And, of course, the drivers are so competitive. Everyone wants to beat the car in front of them and inch their way to the front to win.

This year, it was interesting to see drivers from other racing championships and categories try a race or two in the RX-8 Cup. Some of these drivers are seriously accomplished and competitive in their own categories. They raced against us and couldn’t win. They’d say things like, “Gee, it’s harder than I thought!” and “The cars are so similar!” Some of these drivers achieved a top-five finish but they struggled to get to the front. This really expresses the closeness of the racing in the RX-8 Cup.

It’s for anyone who wants to race door-to-door and improve their competition driving skills and race craft. The RX-8 Cup is ideal for any racing driver who wants to challenge themselves without relying on the car to make the difference in their results.

Mastering the RX-8 Cup then means having to master corner-entry braking, in-corner speed and the ability to apply corner-exit traction. This is particularly difficult given the cars in the RX-8 Cup are production-based and relatively heavy at 1,360 kilograms. That’s quite light for a fun sports car but requires skill to manoeuvre in a race.

I’d say the RX-8 Cup is also suited to anyone stepping up from Karts who wants to start racing cars

Any Series 1 Mazda RX-8 with a manual gearbox (2003 – 2008). The RX-8 Cup in Australia has specific technical regulations the cars need to meet before they’re eligible to compete.

There are some important safety-related modifications that need to be made, such as the installation of an approved interior roll cage, the fitment of an FIA-approved driver’s seat and an approved safety harness.

Many of the items fitted to the cars are ‘controlled’, which means they are determined by the rules of the class and the same on all competing cars. For example, the wheels, tyres, brakes (discs and pads), exhaust system, suspension, engine air intake and rear wing are all control items on the cars.

There are many items you can’t change on the cars. For example, the engine’s inlet and exhaust ports must be OEM specification and porting or polishing or honing is not permitted. The engine ECU must be OEM and unchanged. The transmission can’t be modified from original and the fuel tank can’t be changed. Additional fuel tanks can’t be fitted. There are many other vehicle items that can’t be changed under the technical regulations of the RX-8 Cup in Australia.

At the moment (December 2025) I would say around $30,000 or $35,000 for a fairly nice RX-8 Cup car. You could pay up to around $50,000 to $55,000 for a very nicely finished race-winner.

In my case, this year has taught me how to build and run my own RX-8 Cup car for the racing season. I’m currently building my own new RX-8 Cup car for 2026.

I estimate around $50,000 will build you a suitable car.

Costing up a build for an RX-8 Cup racer comes down to your ability and willingness to complete the build yourself. If you are, you need to determine how much of the build you’d like to do, and which elements you’d prefer to pay to have done. Everybody wants to build or buy a racing car that’s capable of winning a championship but it mostly comes down to how much you’re capable of doing yourself and how much you need to outsource.

I’m only able to work on it at nights due to my workday commitments. If I had the opportunity to work on it full-time from Monday to Friday then I estimate I could build it in around two weeks.

I change my car’s engine oil, oil filter and plugs after every race meeting. I also clean out the engine’s air filter.

I also like to replace the brake discs and pads. And I always replace my tyres after each race meeting. That’s my personal preference.

At half-season I replace the car’s clutch. I’ll get a full season from my gearbox and then replace a synchro or two in the off-season.

It’s an old saying but every race win begins in the workshop so it’s important to have a well-built and prepared car.

The engine is a stand-out. A lot of people have a belief that rotary engines aren’t as durable as piston engines but because a rotary likes being revved they’re fine in the RX-8 Cup. The fact they can easily endure so much high-rev driving for extended periods surprises some people.

Also, the RX-8’s suspension components have proved to be impressively durable. There are parts that are near bullet-proof and extremely reliable. Overall, the cars are well balanced and well built.

You would need to check with your local state’s roadworthiness rules but I suggest they wouldn’t be road-registerable once prepared to race in the RX-8 Cup.

In my experience, the RX-8 was a really well-built car from new. It shows in how well they perform in this controlled racing series. Provided you properly maintain your RX-8 Cup car and don’t have a big crash during the season, a car should last a long time.

There are racing RX-8s in our category that that have been competing for years and that’s testament to the original Mazda road car they’re based on.

Jump on to the Mazda RX-8 Cup website and read about the series, how it works and the regulations. Contact the series administrators if you have any questions about joining the series.

If you don’t have a circuit racing licence and you’re starting from scratch, visit the Motorsport Australia website and contact them about how to get started.

And come along to one of the RX-8 Cup rounds held in your state. The series takes place at racetracks in New South Wales and Victoria. Drop by the pit area, introduce yourself to any of the drivers – including me – and we’ll happily answer your questions.

See you there!