With a turbocharged 300bhp engine, rear-wheel drive and Mazda MX-5 underpinnings, this modified Ford Escort Mk4 will question your sanity. 

Feature from Fast Ford magazine. Words: Simon Holmes. Photos: Ade Brannan.

Over the years, we’ve learnt not to judge a book by its cover; after all, there are so many understated sleepers around, hiding virtually every engine combination.

But of all the unsuspecting builds we’ve come across, we don’t think anyone would guess what’s hiding beneath the surface of Robert Thompson’s humble-looking modified Ford Escort Mk4. To guess it might be hiding turbo power wouldn’t be unusual, but making well over 300bhp and putting it down through the rear wheels with complete Mazda MX-5 underpinnings is certainly a new one for us.

Modified Ford Escort Mk4 RWD 300bhp turbo

With that in mind, it will be of no surprise to learn that this modified Ford Escort Mk4 has been built with a single purpose in mind: to have fun.

Its owner Rob says, “It’s no show car and gets driven hard. I usually go through three gearboxes and two diffs a year. But I always muck about in it and it gets driven everywhere; from car shows and meets to on track at Knockhill or drag racing at Crail.”

Rob is no stranger to a rear-wheel drive Ford, having owned many Mk1 and Mk2 Escorts, but more recently he had given the car scene a break as kids took over.

About five years ago, and keen to get back into Fords, Rob built a tuned Mk2 Focus ST with 320bhp. But after a few weeks on the road, he found himself giving the car to his daughter and finding something more to his taste.

Modified Ford Escort Mk4 RWD 300bhp turbo

He says, “I was thinking of a Mk1 or Mk2 Escort, but you just can’t drive those hard anymore. I wanted something I could drive like an idiot and if I bent it, I could walk away and build another.”

That’s why this Mk4 Escort caught his eye when he saw it advertised on eBay as an unfinished project. The car was rolling and didn’t run but, on the surface, didn’t appear to need a lot, so he decided before he got there that if it was structurally sound, he would buy it. Rob was able to inspect the car on a ramp and was pleasantly surprised by the way it had been put together by a mechanic.

He recalls, “It had been built well but needed a lot of finishing. It was basically just mocked up and the subframes only had a couple of bolts holding them in place.”

It may have needed a lot of work but, on the plus side, most of the hard stuff had been done. It had even been painted, although Rob ended up having to redo some of that.

The conversion itself had been done well and it wasn’t just the top of a Mk4 Escort plonked on top of a Mazda MX-5 chassis. The front end had been adapted to fit the Mazda subframe, which allows the entire MX-5 front suspension, steering setup and engine to mount in place. Further back, the original Ford floorpans remain in place with a transmission tunnel added, and at the rear, the Mazda subframe had been fitted to allow the complete rear axle to fit. The car also featured the Mazda wiring loom, including the clocks and instruments.

“It drives just like a normal car,” Robert says. It also looks like a normal Escort inside and out, thanks to the black bumpers and Bonus trim, complete with carpeted interior over the new gearbox tunnel and rear seats fitted in place. Despite the odd tell-tale, it would be hard for anyone to ever guess what was underneath, which is what makes this car such an awesome build.

Modified Ford Escort Mk4 RWD 300bhp turbo

But although everything had been fitted nice and straight, Rob wasn’t happy with some of the strength in places. And, having been a professional mechanic in the past, he knew his way around a car – although he’s now a semi-retired fisherman, which means he has plenty of free time on his hands.

Rob confirms, “It needed extra strength, so I remounted the rear subframe with 30mm box section like we did with stock cars years ago. There were a few other bits and bobs to go over, and then I did the same at the front by strengthening the subframe. I then lined it all up as best as I could with strings.”

With the car up and running in just a few short weeks, Rob took to the roads to enjoy it. But unfortunately that didn’t last too long, as in standard form the Escort didn’t quite have the fun factor he was looking for.

He recalls, “I drove it for 14 days before deciding it needed more power. So I fitted the G19 Engineering turbo kit, which came with a turbo, intercooler, downpipe, all the lines and fittings and a standalone ECU.”

The car made respectable 250bhp in this new guise, and in doing so, transformed the way it drove, dramatically improving the hooligan factor he was looking for.

It was good enough to stay that way for some time too, but eventually Rob found himself wanting more. So he rebuilt the engine to a far fancier spec, with forged internals, a ported head and capacity increased to 2.0-litres. Fitted in place together with a much larger TD05 turbo, it ended up making an impressive 400bhp, but the driveability suffered.

Rob remembers, “You had to redline it in every gear to stop the turbo dropping off during a gearchange. So I decided to put a smaller TD04 turbo on it, which makes it more driveable and it still makes a solid 315bhp at the hubs.”

The result from all that power in a modified Ford Escort Mk4 with a lightweigh shell and rear-wheel drive is a car that keeps him on his toes… And that’s the way he likes it.

Rob laughs, “It’s great fun in the dry but dodgy in the wet. At 70mph it will spin the wheels and go sideways, which is a bit sketchy but I used to race motorbikes and I love rear-wheel-drive stuff.”

But after five years with the car and untold amounts of fun, Rob admits he’s not sure what to do with it next.

“I was going to sell it, but then I drive it again and it puts such a smile on my face. Even my daughter likes to drive it,” he explains.

We can’t imagine anyone would grow tired of surprising people with a Mk4 Ford Escort Bonus that looks the way it does but drives in such a wild style, so we can’t imagine it’s going anywhere soon.

Tech Spec: Modified Ford Escort Mk4 Turbo RWD


1839cc Mazda BP DOHC engine, over-bored to 2.0-litre capacity, custom MAL pistons, Manley Performance steel conrods, high-pressure oil pump, ported and flowed cylinder head, mushroom-style air filter and custom intake pipe, 640cc fuel injectors, G19 Engineering turbo manifold, TD04 turbo, custom exhaust system, ME221 ECU


315bhp at the hubs


Rear-wheel-drive conversion using Mazda MX-5 NC six-speed gearbox, uprated clutch, Mazda MX-5 rear axle with limited-slip differential


BC Racing coilovers all round


Mazda MX-5 brakes all round, with uprated discs and pads, remote brake booster, and external reservoirs

Wheels & Tyres:

7x16in Lenso D1R alloy wheels, 4×108, with 205/45/16 tyres


Escort Bonus three-door, rear spoiler, bonnet vents, clear front indicators, tinted rear lights


Trimmed interior, Bride bucket seats, Bonus rear seat, Mazda MX-5 clocks and dash instruments