Built at home and with 400bhp on tap, this sober-looking modified Ford Sierra wagon is a true homebuilt hero.

Feature from Fast Ford magazine. Words: Simon Holmes. Photos: Andy Saunders.

Sometimes you find yourself falling into a project without even meaning to. But it’s often those kinds of builds that turn out best. With no tune to follow, the natural process of fate will find a way of helping.

And that’s exactly how Kurt Tann turned this cheap-and-cheerful Ford Sierra into an awesome homebuilt street sleeper. Thanks to a turbocharged home-brew special under the bonnet and an unsuspecting look inside and out. Kurt has built a truly unique fast Ford.

As he likes 1980s’ Fords, Kurt has owned a few over the years. He was in the process of rebuilding a Mk2 Orion and Mk3 Granada when he first heard this Sierra was up for sale.

Front on shot of modified Ford Sierra wagon

Kurt recalls, “A friend was eyeing the car up and decided against it. He had sent me the details, and after a chat I decided if he wasn’t going to have it, I had to have a look. I had no interest in Mk2 Sierras at all, but at £250 I couldn’t knock it for a rear-wheel-drive Ford.”

Sure enough, the car appeared to be a bargain. Not only was it a tidy example, the engine bay and interior were spotless. Aside from a couple of small bits, the bodywork was decent too. Plus it had every service stamp, past MOTs and a whole load of history.

ST170 engine in modified Ford Sierra wagon

But although it was great buy, Kurt didn’t have much need for the car.

“It sounds odd, but I purchased it because I thought the rear end was that ugly it looked cool,” he explains.  “I had no idea what to do with the car. All I actually planned was to run it through summer 2015. Go to the Classic Ford Show and then sell it to crack on with my other cars.”

dolphin tip exhaust

Rolling project

That soon changed, as fate began to play into his hands. The car became a rolling project after a small bump while driving on ice. Thus discovering the trusty Pinto needed attention.

Kurt says: “As I straightened out the damage, I found the stem seals in the original engine had gone hard. I figured I’d drop a Zetec on bike carbs into it, which I had sat waiting on a pallet.”

Along with a few other upgrades and additions, the Sierra soon began to pick up pace. This picked up further when a bet with a mate in the pub led to a budget-build Zetec turbo conversion. That saw a few revisions when it came to plumbing and manifold configurations. It all ended up making a healthy 275bhp and led to bigger things.

Dials in modified Ford Sierra wagon

“When that motor died after a drag racing day out in 2019, I decided if I was going to do it again, I would take the time and do it properly. So, the ST170 turbo idea soon came about from chatting about specs with a couple of mates,” remembers Kurt.

The current build is the best yet and revolves around a heavily reworked ST170 engine. This is complete with forged pistons, steel rods and a tickled cylinder head. To go with it is a large GTX3076 turbo that has been fitted using Kurt’s home-brewed skills. For instance, the exhaust manifold is a Nissan 200SX item that has been heavily adapted to fit. The same goes for the inlet plenum, which started life on a Mitsubishi Evo and has been modified to fit the ST170 lower manifold.

roll cage in rear of modified Ford Sierra wagon

Kurt explains, “I did pretty much the majority of the work. Bar a couple bits of alloy TIG welding and the odd piece of help here and there where I’ve not been able to access kit. The majority I did between sheds at home by juggling space.”

Other custom parts with Kurt’s input include the sump, plumbing and external oil pump setup. A;though he tells us the trickiest job was something that looks much simpler. “The hardest part was actually getting the US-spec rocker cover to fit. It involved coupling an ST170 and US-spec Zetec cover into one.”

rear steel wheels on modified Ford Sierra wagon

Essential upgrades for the modified Ford Sierra wagon

To continue the mixed-and-matched theme, the engine is attached to a Mazda RX-8 gearbox.  This has an an uprated clutch, and powers the wheels via a proper plated-type LSD. The combination is incredibly effective. Kurt says the car performs very well, so far running a best of 415bhp and 335lb.ft of torque. Having previously managed a best of 13.5 seconds in the quarter-mile with 275bhp, the new setup is yet to be properly tested but should be quicker.

While the running gear has been heavily reworked and the exterior detailed, the inside remains standard-ish, which was the plan.

Standard sierra seats

“Anyone that’s owned a Sierra knows how comfy they are.  I didn’t want to lose that and bought a scrapper GLX estate for just £40 with a mint interior,” Kurt laughs. Sure enough, the combination of comfort and performance make the car a joy to use. Kurt tells us it’s at home on the road as much as it is on the strip.

“It actually drives pretty well day-to-day,” he explains. “It’s definitely still useable on the road, albeit Cornish roads aren’t the most forgiving. The majority of the time it’s just used for going for a drive and enjoying at the occasional drag day.”

Gear lever in sierra

More and more

As with any home build, there’s still more to do. Kurt has plans to tune the car further and make some improvements.

He explains, “I want to dial the VVT in. Drop the exhaust housing size a bit to move the boost range a bit lower. There’s also a Supra diff to go in the back end. As well as with a spare rear beam that’s destined for the chop saw to make it fully adjustable. Plus, I’d like to beef up the fuel system, add some more boost and sort out a few project niggles.”

With no end in sight but more ideas in the pipeline, we expect to see Kurt fermenting the modified Ford Sierra wagon more.

Side profile shot of modified Ford Sierra wagon

Modified Ford Sierra Wagon images

Tech Spec: Modified Ford Sierra Wagon


1988cc ST170 Zetec engine, home-made sump, ARP bottom end studs with custom adapters to run windage tray, standard crank, PEC steel H-beam rods, ARP rod bolts, Focus RS-spec forged pistons with custom valve pockets, decked ST170 block, MLS 0.6mm head gasket, ARP head studs, ST170 head with exhaust ports flowed and polished, Peugeot 106 GTi Newman Cams 160lb valve springs and retainers, Toyota Yaris coil-on-plug setup, home-made external oil pump setup, home-made water rail, Garrett Gen 1 GTX3076R turbo, home-made exhaust manifold (Nissan SR20-based), home-made plenum (4G63 Mitsubishi-based), modified runner and throttle body flange to suit ST170 lower inlet, 80mm throttle body, Siemens Deka 875cc injectors, 280 litres-per-hour fuel pump, Facet lift pump, home-made swirl pot, 8mm copper fuel lines, Zetec-to-Cosworth lightened flywheel, home-made 3in exhaust, custom US-spec/ST170 rocker cover, modified Sierra Cosworth radiator, modified RS500-style intercooler, home-made 2.5in boost pipes, Range Rover cooling fans, Ecumaster EMU Classic engine management


Mazda RX-8 gearbox, custom Zetec-to-Mazda RX-8 adapter plate, hydraulic clutch conversion, CG Motorsport Stage 3 Cosworth clutch kit, home-made propshaft, Titan Motorsport plated limited-slip diff with adapted stub shafts


Front: Gaz coilovers, Mk3 Granada anti-roll bar; rear: Gaz coilovers, XR4x4 beam; polyurethane bushes throughout


Front: Sierra Cosworth four-pot callipers and discs, rear: Sierra XR4x4 discs and callipers; braided lines all round

Wheels & Tyres:

7x16in Citroen steel wheels with 165/45R16 tyres


Sierra GLX estate trim, LD Performance dash display, Safety Devices six-point roll cage


1990 Sierra LX estate, strengthened rear turrets, boot floor/rear wheel well removed, Ford optional front splitter; paint: Maritime Blue with red bonnet