New hybrid turbo conversion endows the Fiesta ST with Focus ST power.
It wasn’t so long ago that the largest amount of power you could put through the front wheels was considered to be around 185kW. But today many hot hatches are putting huge power through the front axle with no great difficulty. The recently departed Honda Civic Type R had 235kW, while the Renault Mégane RS and Hyundai i30 N get close.
But those are cars developed from the factory to have big power. It’s another story entirely when you boost a car after the fact. So what happens when you massage the turbocharger on the Ford Fiesta ST to take it from 147kW to approximately 210kW? Here to help us find out is Turbo Technics’ new S285 conversion which we’ve been able to drive in the UK. Turbo Technics kits are available in Australia via some tuners, although this shiny new mod for the Fiesta ST is only on roads around Britain for now.
If you haven’t heard of Turbo Technics, they’ve done this sort of thing before. Working at Garrett in the 1970s, Geoff Kershaw was instrumental in the development of the turbo engine in the Saab 99 before he struck out on his own and started Turbo Technics in 1981. Since then, the firm has offered turbo kits for various cars, from the Ford Capri to the Nissan Figaro and the Volkswagen Golf R (easily capable of 410kW, apparently) – although a lot of their business comes from turbo refurbishment and turbocharger-balancing machines.
The S285 uses a so-called hybrid turbo. There are no batteries involved; it’s not that kind of hybrid. Instead, Turbo Technics takes the standard turbo and guts most of it, uprating the shafts, compressor wheels and bearings and modifying the housing to optimise the shape for power, rather than efficiency.
The internals reportedly take the extra power with little complaint, although Kershaw admits that there will always be some trade-off in the longevity of some components. While internal upgrades aren’t essential, some supporting modifications are. An ECU tune, an uprated intercooler, an induction kit and a freer-flowing exhaust ensure the turbo’s increased potency isn’t wasted.
As you might imagine, then, this is a thorough job, and there’s little to criticise about the turbo conversion itself. Granted, there is more lag than with the standard engine, and it wants at least 2500rpm on the tachometer before it really wakes up, but the more old-school turbo experience is very exciting, and it’s accompanied by the full complement of whooshes and chuffs.
It feels quite content to headbutt its 7000rpm limiter, too, at no point feeling strained, while also remaining perfectly tractable at low revs, with no hesitation or roughness.
If there is some coarseness, it’s from the Scorpion exhaust. At low revs it grumbles; at higher revs it shouts obnoxiously; and in general it buries any three-cylinder character under a loud blare. Kershaw says that it was the only system available when they started developing the turbo, and you’re welcome to choose a different exhaust, as long as it’s less restrictive than the standard one.
While the turbo conversion is brutally effective, it’s right at the limit of what the chassis can handle. On the cold winter’s day we drive it, it’s well over it.
If the boost comes in midway through the corner, the Michelin Pilot Supersport tyres will break traction quite suddenly and give up any attempt to follow the chosen cornering line. Lift off and the Fiesta’s naturally playful balance comes into play and quickly converts understeer into oversteer.
Things improve as the road dries out, and the traction control actually does a good job of managing things if you just want to get from A to B, but it’s always going to be a raucous experience with plenty of torque-steer and one that will be frustrating on cold, wet roads.
Turbo Technics sells the kit through tuners, who bundle the turbo with all the required supporting modifications in one package. Alternatively, the turbo on its own can be purchased on an exchange basis with your standard turbo.
The question of whether it’s a worthwhile upgrade will depend on what you want to do with your Fiesta ST. If you just want a bit of extra poke from your everyday and all-weather road car, Turbo Technics’ kit is overkill. However, there will be those who want the fastest Fiesta ST, one that’s faster even than the Focus ST, just for the hell of it. In that case, or for a dedicated track build, this is a great option. Just don’t expect it to be as well-rounded as something that was designed from the outset with this level of power.