The Fiesta ST Mk7 is one of the best bang-for-your buck performance hatches available today. With a nimble, well-balanced chassis and potent 1.6T EcoBoost engine, this little Ford already punches above its weight. But there’s so much more potential waiting to be harnessed.
We’ve spent the last four years developing performance products specifically for the Fiesta ST Mk7. In that time, we’ve got to know these cars inside out. Our best-selling STG1 and STG2 ECU packages have been carefully developed to enhance the car, without altering its character, but having reached the limits of the stock turbo, the next step was to develop a bespoke turbocharger set-up.
Having identified the size of the stock turbine housing and internal wastegate as the main restrictions, we set about developing a big-turbo set-up from scratch. Although hybrid units are available for the 1.6T EcoBoost, we firmly believe that a big turbo is the better performance option. It was essential that the package delivered more power, but without the high boost levels and associated stress of a hard-worked hybrid. As with any PERON product, the watchwords were Performance, Drivability and Durability.
One of the main restrictions with the 1.6T engine is the stock turbine housing and internal wastegate. While hybrid turbochargers can offer increased flow, they must run higher boost levels to achieve this, which can compromise reliability. We wanted to develop a package utilising a big turbo, so that we could achieve more power, but without having to run so much boost. Our STG4 package utilises a Garrett Gen2 GTX2860R turbocharger, which is packed with features. Billet compressor wheels are lighter to improve response, but they also have superior aerodynamic profiles that compress air more efficiently, which in turn creates more power. The latest low-friction ball-bearing centres are used for improved response and the V-band Entry Turbine Housing in Ni-Resist has been proven to not only improve flow and spool faster, but also provide ease of installation with a durable gasket-free seal.
Developed by our in-house technical partners, Nortech Performance and beautifully crafted from T304 stainless steel, this robotically TIG-welded component features a CNC-machined billet merge collector, along with optimised primary dimensions and CNC Nortech signature head flange. Not only does this bespoke manifold optimise exhaust gas flow, it also looks like a work of art.
Included with the package is a PERON high-flow de-cat downpipe. Manufactured from T304 stainless steel, including flanges, flexible section and lambda bosses, this robotic TIG-welded component has been specifically designed for use with the Garrett turbocharger. Please note: this item is designed for off-road use only. We are currently working on a sports cat downpipe solution that will be available in March.
Key to any aftermarket turbocharger package is ECU calibration. For this we turned to our senior in-house software specialist who has over 20 years’ experience with Bosch ECUs. The software has been developed specifically for the turbo set-up on this car, allowing us to achieve stunning results. Boost control is flat and consistent throughout and timing is optimised to suit the lower back pressure. We’ve spent many hours on the dyno as well as testing on the road, to ensure our calibration works in perfect harmony with the STG4 turbo package.
Our STG4 package has been rigorously tested on our own Fiesta ST development vehicle. We have driven it in every real-world situation you’re likely to encounter, from fast country roads, to stop-start town driving and, of course, on track. The car has also been subjected to many hours of dyno development to ensure it meets our stringent demands of performance, drivability and durability.
The PERON STG4 turbocharger package will take 2-3 days to install. This includes essential pre-checks to the car, as well as full testing and dyno runs. Installation can be carried out at our Barnsley HQ, or at one of our selected global dealers.