Mountune is best known for tuning turbocharged Fords for increased power. They offer a wide range of aftermarket performance parts for cars like the Fiesta ST and Focus RS , but now the company is stepping into the world of Volkswagens . Instead of keeping the Mountune name, they're collaborating with U.S. wheel manufacturer fifteen52 and calling themselves m52.One of the big reasons to go with a Mountune "tune" over someone else with a Ford is because they offered services that didn't void the original Ford warranty . We asked Mountune if its VW products are approved under the Volkswagen warranty, and learned that they are not covered. What the website does say, is that all m52 products have a 12-month/12,000-mile warranty. Still, that's very different from keeping your long Volkswagen warranty for your engine.In the beginning, m52 is offering Stage 1 tunes for the Mk7 GTI and Golf R . The GTI gets raised to 306 horsepower and 350 pound-feet of torque. Volkswagen says that drops the 0-60 mph down to just 5.4 seconds with the manual transmission. No time is quoted for the DSG, but the DSG version of this tune also recalibrates the transmission. The tune features an "enhanced launch control," a "return to stock and valet mode," and an m52 badge.Only a British price is listed on the site for now, but m52 makes it clear that its products are available in the U.S. too. Converted from pounds sterling, the Stage 1 tune for the GTI costs $863.61.Of course, a Golf R tune is also available, upping power to 355 horsepower and 369 pound-feet of torque, This is said to be good for a 0-60 mph run in just 3.7 seconds with the DSG. The Golf R tune comes with all the same features as the GTI tune did. It's recommended that you use m52's aftermarket induction system with the tunes to achieve every last bit of the performance gains, but is not necessary according to m52. The Golf R tune is the same $863.61. It's another $433.44 for the induction system from m52 — the system is capable of supporting cars with up to 600 horsepower.The website has a bunch of other performance parts on it for the GTI and Golf R, and they're offering 5% off everything until the end of May.