PistonHeads - December '13



The purist in you might argue that turbocharging an MX-5 goes against the whole point of the car. Indeed the very joy that comes from making maximum progress from minimal power is, for many, the whole point. Jinba ittai just kicked in, and all that.

But the purist in you is going to have a very time making himself heard after driving BBR’s GT270.

Depending on your outlook sodden British B-roads in the pouring December rain are either the last place you’d want to be driving a 268hp rear-wheel drive roadster with the roof down. Or very possibly a vision of spray-soaked driving nirvana.

For sheer laugh out loud fun it’s sure hard to beat, the experience being all the things those of us who love the MX-5 witter on about conducted at a much, much faster rate of knots and with considerably more time on opposite lock.

Life and soul
If adding a turbo to the MX-5’s motor had turned it into some modded one-trick pony huffing and puffing its way through sudden boost spikes that purist might have cause to look down on it. But this GT270 conversion, available through BBR directly or via Mazda dealer MGK3000 in Twickenham, is nothing of the sort. Chatting with BBR’s Neil Mckay before heading out into the winter gloom he’s keen to point out the power delivery is intended to mimic that of a standard car, just more so. Much more so.

Running a modest 0.5bar of boost means the turbo’s entry to the party is less unwelcome gatecrasher than unexpectedly entertaining life and soul. There’s little of the lag or all-or-nothing power delivery found in the overboosted 1.6s to which we’re becoming accustomed, the natural grunt of the 2.0-litre meaning BBR can engineer a commendably seamless addition of extra verve with peak power at 7,350rpm and peak torque of 227lb ft – 88lb ft more than standard – at 5,100rpm. 200lb ft is available from 3,000-7,000rpm, giving you a wide operating window in which to exploit that extra go. And it even sounds pretty stealth. Or does as stock, Neil admitting that his personal map has a bit of extra fuelling to unleash flurries of pops and bangs at strategic moments.

Discrete feel or not, there’s another 100hp+ over a standard MX-5 here. And a savagery and intent you’ll never have felt before in a normally aspirated one. There’s a hint of being aboard a lit firework but such is the inherent balance of the base package it never feels overwhelmed. Considering how much more power there is than standard the delivery is beautifully progressive, meaning dab-of-oppo opportunities are there for the taking across the performance spectrum on mid-winter back roads. Or you can play it fast, neat and tidy according to taste with the effortless overtaking ability simply meaning more time with the open road to yourself. Fierce, BBQ-style seat heaters mean this can be conducted al fresco even at this time of year too.

Potent, poised, pricey?
Fair to say, the demo car we drove was fitted with BBR’s Koni damper/custom spring suspension kit and the 35mm front/30mm rear ride height drop and greatly reduced pitch and roll over the standard car will play a big part in containing this significant performance hike. As it stands the £29,995 GT270 package is centred on the engine and comprises the turbo and intercooler hardware (including a stainless steel manifold), high-flow injectors, four-mode ECU, uprated Exedy clutch and various other bits and bobs required.

With the suspension kit the MX-5 has a sense of poise and purpose to match the significantly increased potency. Weight transfers are contained, steering feels more hefty and positive on turn-in and even on greasy, choppy B-roads the damping combines a buttery smoothness with confidence inspiring control. That’ll be a very worthwhile grand added to the price then.

Folding hardtop (now the only choice on 2.0 MX-5s) stowed there’s a degree of shimmy through the MX-5’s body and steering column that is possibly your only reminder you’re driving a car intended for 160hp and not 270. But it’s not enough to detract from the novelty of driving an MX-5 that would show a Boxster a clean set of heels down most British back roads. If the surprise factor didn’t catch them napping the power delivery certainly would – such is the inherent flexibility of the installation you can lean on significant in-gear punch or shift down for a more exuberant version of the same and in the time it would take the Boxster to wind on some revs you’d be disappearing into the distance with a fat grin on your face.

Sure, snobs are still going to see it as just another bloody MX-5 but the GT270 is just such a giggle you won’t care. And if the idea of spending £30K+ on a Mazda doesn’t appeal you can always retrofit it to an existing or secondhand car. Let’s just say the 270hp of this semi-official package is conservative and 300hp-plus is merely a free-breathing exhaust away with more to come if you really want to get daft.

With plenty of Mk3s around from £5K or so the potential is there to build a proper giant killer on a budget, even if the idea of spending the equivalent of the car’s purchase price in a turbo kit is going to require some fairly robust man maths. In case you’re interested BBR’s 260hp Stage One kit – more or less the same as the GT270 – is £4,995 fitted and the 302hp Stage Two kit £6,995. Both are available as DIY packages, which saves a little up-front expenditure.

As an off the shelf package the complete GT270 is probably an easier fiscal argument to make but that won’t be enough to head off the inevitable ‘£30K for an MX-5?!!!!’ outrage. As it stands BBR and MGK will only be selling 100 of these limited edition models but Neil’s door will always be open if you’ve got a standard car and a taste for a dose more speed. And if your purist side really can’t handle the idea of forced induction there’s always the normally aspirated Jota MX-5 GT instead.

Engine: 1,999cc 4-cyl, turbocharged
Transmission: 6-speed manual, rear-wheel drive
Power (hp): 268hp@7,350rpm (160@7,000rpm)
Torque (lb ft): 227@5,100rpm (139@5,000rpm)
0-62mph: 4.9sec (7.9sec)
Top speed: 150mph* (136mph)
Weight: 1,248kg (standard car)
MPG: 36.2mpg (standard, NEDC combined)
CO2: 181g/km (standard)
Price: £29,995 (£23,095 for 2.0i Sport Tech Roadster Coupe)
(Specs, where different, for standard car in brackets)

Author: Dan Trent



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