{"id":51085,"date":"2026-06-09T10:00:41","date_gmt":"2026-06-09T08:00:41","guid":{"rendered":"https:\/\/www.italpassion.fr\/?p=51085"},"modified":"2026-06-08T09:54:23","modified_gmt":"2026-06-08T07:54:23","slug":"these-two-alfa-romeo-mito-prepared-with-290-and-425-hp-scare-the-audi-s3-with-a-simple-1-4l-engine","status":"publish","type":"post","link":"https:\/\/www.italpassion.fr\/en\/alfa-romeo\/ces-deux-alfa-romeo-mito-preparees-a-290-et-425-ch-font-peur-aux-audi-s3-avec-un-simple-moteur-1-4l\/","title":{"rendered":"These two Alfa Romeo MiTo tuned to 290 and 425 hp give the Audi S3 a fright... with a simple 1.4L engine."},"content":{"rendered":"
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A few days earlier, we presented a 400 hp Alfa Romeo Mito prepared in Greece for hill-climb races<\/a>. We explained that SLP Tuning, the tuner, was no stranger to body-built Mito models. Here are two models presented in 2024 in the leading Greek magazine, Power Automotive magazine.<\/p>\n\n\n\n

L'Alfa Romeo MiTo<\/a>, In addition to its successful design, the best versions of this model were equipped with high-performance powertrains. A small 155 hp turbo engine, three driving modes (DNA), firm suspension, four-piston front calipers and a well-spaced six-speed gearbox. When it comes to the preparations involved in this subject, achieving such a high output per liter on a small engine means modifying certain parts.<\/p>\n\n\n\n

Version 425<\/h2>\n\n\n\n

The engine features Wossner oversized forged pistons and ZRP forged connecting rods. The cylinder head benefits from SLP Tuning services to optimize efficiency and reduce parasitic friction, with camshafts \u201cHot Street Dirt Track\u201d<\/em>. Surfacing, flow optimization and machining have resulted in optimum performance.<\/p>\n\n\n\n

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The custom-made SLP Tuning cylinder head gasket maintains the compression ratio at 9.5:1. At the front of the engine, protected by its thermal insulation blanket, sits the Garrett G 25-550 turbocharger, a well-established solution. Of course, the 1.4T engine is a bit limited, since Garrett sets the minimum displacement for such an imposing turbo at 1,400 cm\u00b3, but the pressure rises sufficiently for trouble-free inflation. To ensure that the G25-550 fits properly, an octopus-shaped exhaust manifold was custom-made. Finally, GP Exhaust took over for the 70-inch exhaust.<\/p>\n\n\n\n

Up front, it's much simpler: a RamAir cold-air intake kit, a big Mishimoto J - Line intercooler with hand-made intercooler pipes by GP Exhaust and a water-methanol kit. Simply inject more fuel with Bosch injectors delivering 630 cm\u00b3 \/ min and provide power with cooler NGK spark plugs. <\/p>\n\n\n\n

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