UK performance tuner BBR has taken the lid off a turbo conversion for the smaller 1.5-litre Mazda MX-5.
Previously available only for 2.0-litre models, the Brackley based Mazda tuning legend has managed to re-engineer the upgrade to enable its installation in 1.5-litre powered versions – where it provides a significant boost.
Designed for easy installation without requiring mechanical alterations, the BBR Stage 1 turbocharger upgrade raises peak power to an impressive 157kW – or 60kW more than the standard output.
Equally important says BBR is the spread of power – more than 112kW is available from 4000 rpm all the way to the 7750 rpm limiter.
This is allied to maximum of 267Nm of torque (116Nm more more than stock), which arrives at just 4150rpm, with over 203Nm on tap from 3000rpm to just under 7000rpm.
It’s an immense spread of performance that transforms the 1.5-litre MX-5 driving experience for the better, irrespective of road or track conditions.
“BBR’s early development work proved Mazda has done a great job with the 1.5-litre SKYACTIV-G engine, so power gains beyond remapping without forced induction and considerable effort are likely to be negligible,” BBR’s Neil McKay said.
Accordingly, one of the key elements of BBR’s Stage 1 turbo upgrade is the adoption of BBR’s exclusive twin-scroll TSX28-67R turbocharger, which has been specially selected to match to the different characteristics of the 1.5-litre engine.
“BBR’s decision to use twin-scroll turbo technology has been validated by the positive media and market feedback on the initial conversion for the 2.0-litre ND models,” McKay said.
“For the 1.5-litre SKYACTIV-G engine, the main development effort focused on turbo matching to suit our desired twin goals of transforming the everyday driving performance, whilst maintaining the rev-free nature of the smaller power unit.”
The twin-scroll unit that BBR has selected features a bespoke latest generation billet compressor wheel and lightweight, low inertia turbine in a compact, internally wastegated assembly.
The resulting turbocharger is a highly efficient and responsive forced induction solution, yet retains a large boost upgrade margin for later power stages and considerable further tuning potential.
“We feel that at last we can give the 1.5-litre MX-5 model the performance that it deserves, which is great news given that only a few select countries received the larger 2.0-litre variant.”