Charge Of The Light Brigade – MX-5 GT270

- August 27, 2015 - 6

Product Focus: BBR Mazda MX-5 GT270

If we were to play a game of word association leapfrog, how many ‘jumps’ would it take to get from Mazda to BBR? From the perspective of MX-5 enthusiasts in the UK, it could be as little as two, for there is no other tuner with as close an association with the Hiroshima marque as Northamptonshire-based Brodie Brittain Racing (BBR).

MX-5 Turbo (4)

In recent years, the BBR’s tuning conversions for MX-5s have been acclaimed in every UK car magazine of note, while the secure ‘e-tuning’ facility of preferred ECU partner EcuTek has enabled BBR to market, supply and remotely tune its conversions in as many countries as the MX-5 itself is available.

MX-5 Turbo (23)

But the affiliation between BBR and the MX-5 goes back much further than recent history. Twenty-five years ago, the already highly respected tuner developed and produced an official power upgrade for Mazda UK that went on to become the world’s best-selling turbo conversion for the little roadster. Continual refinement maintained the popularity of BBR’s aftermarket turbo conversions for first- and second-generation MX-5 models well into the New Millennium. By which time the range had expanded to include a BBR-Cosworth supercharger conversion for the third-generation car. Such expansion meant that it was possible for BBR to offer naturally aspirated or forced induction tuning options for every single MX-5/Miata derivative, whether imported or officially supplied.

MX-5 Turbo (36)

Ignoring for a moment the tantalising prospect of a BBR-tuned fourth-generation MX-5 (development is already underway), the latest creation from the Brackley outfit is this back-to-the-future turbo conversion for all 2005-2014 third-generation models. Driven by customer demand for an alliterative cocktail of properly potent performance, the limited edition 268bhp GT270 package distils a quarter century of forced induction expertise to transform the MX-5 into a giant-killer. Indeed, so confident was Mazda and BBR of its engineering and EcuTek software that, just like the original BBR-developed MX-5 Turbo of 1990/91, this boosted car could be purchased as a complete and fully warrantied new car package from selected UK main dealers.

MX-5 Turbo (11)

This particular example is the very first in a strictly limited build of just 100 cars. Based on a last-of-the-line Mk3.75 MX-5 2.0-litre Sport Tech Roadster Coupe, it belongs to the creator of the GT270 package – BBR’s main man, Neil McKay. With an extensive catalogue of goodies to choose from, Neil has applied his very best ECU recalibration, conversion plumbing, chassis setup and engine-breathing know-how to perfect this car, which in our minds makes it the very best of the best. So in a News at Ten style, here are its headlines: 0-60mph in 4.9 seconds, 150mph electronically limited top speed, 268bhp and 227 lb/ft, and specially developed switchable ECU functions.

MX-5 Turbo (17)

Although this BBR MX-5 GT270 clearly has a lot to shout about, discretion is the order of the day in terms of the car’s external appearance. A walk-around tour reveals tasteful ‘BBR turbo’ badges above the side repeaters and on the boot lid, further BBR branding engraved into the exhaust tailpipes, and a lower-slung ride height. The latter feature comes from the fitment of BBR’s optional performance suspension upgrade, which comprises Koni adjustable dampers and specially developed progressively wound BBR lowering springs. Nothing else stands out, so to all intents and purposes the car could be standard.

Lifting the bonnet reveals a very different story, of course, with bespoke carbon fibre components, new intake pipework and a bespoke high-mounted Garrett turbocharger staring back at you in a Tetris-like marvel of packaging efficiency.

MX-5 Turbo (35)

A closer look at what’s going on under there also reveals evidence of impressive attention to detail. For example, careful design and the adoption of that unique turbocharger layout means that no bodywork has to be cut or drilled during the installation of the conversion; it isn’t even necessary to remove the front bumper to fit the front-mounted intercooler and associated pipework. Meanwhile, the battery, coolant expansion bottle and other ancillaries remain in their original locations, and the standard air box is also retained because its cold air intake is known to be highly effective. In fact, so sympathetically carried out is the conversion that it is easy to revert the car to standard… but only if you’ve taken leave of your senses.

MX-5 Turbo (34)

In many ways, the GT270 remains as civilised as the original car. Without an optional exhaust system to amplify the combustion cycle, this modified ‘Five could be even quieter on the move due to the muffling effect of the turbo. But like prodding a sleeping lion, you can be sure that it will let rip when provoked.

The GT25 ball-bearing turbo chosen for this application is quick to react thanks to finely engineered internals and BBR’s efficient manifold and intercooler designs. The boost map is programmed to deliver grunt progressively to a maximum pressure of 7psi, as if the engine was still naturally aspirated. Peak power doesn’t arrive until 7,350rpm – well into the red line – and maximum torque is found at a press-on engine speed of 5,100rpm. Fear not if that all sounds too hectic and peaky, for 200 lb/ft is at the driver’s disposal from 3,000 to 7,000rpm to improve the car’s everyday flexibility and give it an on-demand surge of acceleration irrespective of the gear selected.

MX-5 Turbo (16)

Component choice plays an important role in the driveability of this package but perhaps the most significant contributor is the recalibrated EcuTek ECU, which exploits the full potential of the OEM computer without losing any safety parameters. It even adds extra layers of control so that a suite of desirable functions including launch control, full throttle shifting and rev-matching throttle blips on down-changes can also be offered.

MX-5 Turbo (7)

Now given the equivalent of Mensa membership, the OEM ECU has been programmed with four separate driving modes via EcuTek’s ProECU software. Each of which can be discretely accessed via a special activation sequence using the cruise control toggle on the steering wheel.

The first mode gives access to the full power output and is designed for everyday fast road driving; mode two offers the same no-holds-barred power but uses performance enhancers such as full throttle shifting to optimise the car for circuit driving. Map three shifts the ECU programming into economy mode so the car can cruise along with greater efficiency in lower-grade 95 octane fuel, while mode four engages a security programme that limits engine speed to 3,500rpm to prevent abuse by valet drivers or less competent significant others.

MX-5 Turbo (28)

It is said that there is more happiness in giving than there is in receiving, but we’re sure this fantastic feature brings out the selfish child in all GT270 owners: ‘This is my toy and I don’t want anybody else to play with it!’

MX-5 Turbo (15)

There has certainly never been a faster or more powerful MX-5 available brand-new. With a power-to-weight ratio equivalent to a Porsche Cayman S, a well-driven GT270 has the ability to worry supercars costing many times more. BBR concludes by describing its conversion this way: ‘Cohesive, rapid and understated, the GT270 is the ultimate road-legal MX-5, providing the allure of the BBR Mazda turbo pedigree to an all-new audience.’

MX-5 Turbo (29)

Engine tuning may have become much more sophisticated since 1990 but the passing of almost three decades hasn’t altered the fact that well-engineered turbo conversions still offer plenty of bang for your buck!


More information on brand new MX-5 GT270 models with three-year warranties can be found by following this link, while information on retrofit GT270-style conversions can be found by following this link.

Share on Pinterest
Share with your friends


No comments

Leave a Reply

This site uses Akismet to reduce spam. Learn how your comment data is processed.