The specialist: Silver Fern Performance

By Martin Buckley

| 16 Jan 2026

Classic & Sports Car – The specialist: Silver Fern Performance

Mazda signed up as a licensee for Wankel’s rotary technology in 1961, and soon got to grips with the main issues (having spent $50m on development).

As well as the exotic Cosmo and RX-7, the technology was rolled out in more ordinary-looking models: the 1968-’73 R100 coupé, and the RX-2, 3 and 4 coupés and saloons of 1970-’78 to name just a few.

Today, these early Japanese rotaries are rare jewels that enjoy a cult following in New Zealand and Australia.

Interest is growing fast in Britain, too, aided by rotary specialist Silver Fern Performance of Holywell, North Wales.

The Silver Fern team of (left-right) Sam Reynolds, Lisa Kennedy, Bailey Aislabie, Dwayne Aislabie and Harry Johnson

Founder Dwayne Aislabie is from New Zealand, but came here 25 years ago.

Dwayne was Toyota-trained in his home country then worked in Group B motorsport, creating a hairy, rotary-engined Ford Escort for his boss at Toyota.

He set up Silver Fern in 2014, initially making rotary engines for a French company that built replica Group B RX-7s.

“We were in Deeside, then when COVID-19 hit we moved to Holywell,” he explains. “The interest in the old rotary stuff is increasing.

“My sister runs the office; we have two technicians, and my son Bailey, who’s 15, is starting with us having just finished school – that’s his RX-7 on the ramp.”

Wankel rotary engine work is a key part of the business for Silver Fern Performance

Silver Fern has just completed an epic R100 restoration.

Dwayne says: “It turned up in the back of a Transit in boxes, like a big Meccano set. We have another one we are turning into a race replica – the owner is hoping to get it into Goodwood.”

Works teams of R100s did well in the Spa 24 Hours in 1969 and the Marathon de la Route in 1968.

Thirst and reliability issues killed off the RX as a commercial proposition, and a lot of early parts were binned, but Dwayne got lucky when he bought a lorry-load of new-old-stock rotary items from a man in Scotland: “He was a former Mazda mechanic who rescued the parts from a skip. Panels, nose cones, lights, everything.”

Silver Fern Performance owner Dwayne Aislabie’s Mazda RX-4 coupé showcases his firm’s work

The 2003-’12 RX-8s, last of the rotary Mazdas (current MX-30 R-EV aside), are bargains currently, but rising in popularity and value.

Dwayne says: “A lot have been scrapped and they do rust; we are always welding them up.”

Silver Fern does the structural welding but uses a bodyshop on the same site for paintwork.

“They had a lot of problems with ignition coils,” he continues, “with knock-on effects on the catalytic converters, which cost more than the value of the car to replace.”

Dwayne’s Mazda RX-4 dual-rotor Wankel is mated to a five-speed manual RX-7 gearbox

“On the RX-8 they were looking for a longer, cleaner burn time,” he continues. “I rebuilt one for a lady who was just tootling around, and all it really needed was decoking.

“They can do 100,000 miles and more, but the real value is in cars such as the RX-3, which had a race and rally pedigree.”

The Renesis engine in the RX-8 suffered a variety of problems that can result in coolant in the sump oil, chatter marks on the apex seals and much more.

Rotor housings await attention at Silver Fern Performance in North Wales

In the engine room, four rotaries are sitting ready to complete, including Dwayne’s first NSU Ro80 motor rebuild.

He says: “The Ro80 had peripheral ports, whereas the Mazda’s breathing was less direct. But with all of them, the difficult part is setting up the rotors and getting the clearances right on the side seals.”

Pre-RX-7 rotary Mazdas are now few and far between in the UK.

For his own use, Dwayne has a red RX-4 coupé with a crazy dashboard, a five-speed S1 RX-7 gearbox and an 8-Track stereo.

This tired Mazda RX-3 could become a rally-car project

There’s also a white RX-3 ripe for restoration, but on closer inspection it’s not as rough as it first appears.

“We were going to turn it into a rally car,” says Dwayne. “It was Waxoyled, so that’s saved the body.

“It took a long time to persuade the owner to part with the car. I might put in an FD RX-7 engine…”

Images: Jack Harrison

The knowledge

Name Silver Fern Performance
Address Unit 2 Mostyn Road Business Park, Holywell, North Wales
Specialism Rotary engine rebuilds, performance upgrades and early Mazda restoration
Staff Five
Prices £85+VAT/hr
Tel 01244 820205
Web facebook.com/Silverfernperformance