Much of the MX-5 legend is built on its tuning potential, the scope to create pretty much whatever two-seat roadster you want from the aftermarket a very appealing prospect to a lot of owners. And for PH tastes, the work of BBR is
always of interest
Well why have you stopped driving?
We've already experienced (and enjoyed) BBR's naturally aspirated tuning on the
ND MX-5
, but now it's time for the big power gains with this turbo kit. While the numbers will invariably be first priority - 252hp at 7,150rpm, 236lb ft at 3,250rpm, 155mph and 60 in five seconds - the development of this turbo installation is very interesting too.
Why no supercharger? It doesn't work well with the Skyactiv-G engine, BBR's Neil McKay citing "high parasitic losses" as the problem. The charger would need a lot of boost for the power gains, which would be incompatible with the standard MX-5's high - 13:1 - compression ratio. A single-scroll turbo was also rejected; the 4-2-1 exhaust manifold of the MX-5 is very complex, to exploit exhaust scavenging technology, but a single-scroll turbo creates a lot of back pressure and lacks any potential for exhaust scavenging.
Therefore a low pressure twin-scroll turbo has been used, said to work "harmoniously" with the standard engine and delivering good power with modest boost pressures. The Stage 1 conversion runs at 7 psi, with a bespoke billet compressor and low inertia turbine for the best response possible.
The engine's internals are untouched, with the additional tweaks as part of this kit comprising a new exhaust manifold, a stainless steel downpipe, an intercooler, a dump valve, a K&N induction kit and an upgraded Starchip ECU. The various pipes and lines around the engine have been switched too.
BBR also claims that all Mazda electronic features are retained, with MOT emissions compliance guaranteed and warranties from 12 to 36 months. The kit is fully reversible as well.
And the price? £4,395 plus VAT, or £4,995 as a 'drive in, drive out' kit at BBR in Brackley. The cheapest 2.0-litre available on PH at the moment is this Soul Red car at £17,750. And if just 250hp simply won't do, then let BBR have the last word: "With internal upgrades to the Mazda engine we know that considerably more power is available - the BBR technical team is already developing future stages to exploit this." We'll keep you posted...