Note: Hover your mouse over the “My GTI” link above to reveal a drop-down menu which lists write-ups for various changes to the car.
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I bought a Mk7 GTI because I knew it could be far more than advertised. It started with a reportedly under-rated 220 hp and 258 lb-ft. Dynamometer testing by tuners and enthusiasts indicates that the actual stock output is closer to 235 hp and 270 lb-ft, figures which rival that of tuned engines of earlier generations and already more than my bought-back tuned Jetta TDI. I had watched APR for a LONG time. Although I used other tuners for my TDIs, APR is the only company I considered for my GTI.
I was accustomed to being quite pleased with a 30-hp bump in power from my TDIs after a tune. However, APR’s basic tune bumps the Mk7 GTI’s already-healthy peak output by 81 hp and 111 lb-ft, for a total of 316 hp and 381 lb-ft, even with a factory air filter and exhaust system. Believe it or not, improved fuel economy can also be had with a little self-control… OKAY… A LOT of self-control! 😉 APR was having a sale and my work schedule allowed me to visit a tuner during the week. A Stage 1 tune alone transformed my GTI into a different car. It was quite amazing!
In 2018, I added APR’s downpipe, intercooler, and their Stage 2 software update. That added a small, but nice bump in horsepower and torque. Stage 2 output is advertised at ~337 hp and 383 lb-ft (wheel horsepower less), which is quite satisfying in a 3100-lb hatchback. In 2020, I upgraded the exhaust to a stainless steel cat-back by Baun Performance, LLC. Technically, when coupled to APR’s downpipe, my exhaust is a full 3-inch turbo-back exhaust. Much to my surprise, that exhaust gave me a little more pull up top. I switched to one of Baun’s new “stealth” options in 2022. Click this link to read about a variety of exhaust options for the GTI.
In 2021, I went for even more by upgrading to an IS38 turbocharger and APR’s Stage 3 programming. Coincidentally, two cross-country road trips compelled me to switch to programming that supports 91 AKI fuel. APR advertises its 91 AKI program to produce 395 hp and 371 lb-ft. This dynograph composite shows the difference between Stage 2 and Stage 3 at the wheels while running on 91 AKI fuel. Combined with my 3-inch turbo-back exhaust, I’m very likely beyond the 400-hp mark (360 whp). The car is very eager to get me into trouble by quickly propelling me to Virginia’s “automatic-reckless-ticket” speed of 85 mph, which comes VERY quickly during a spirited pass on a two-lane highway, even with a trailer in tow. HAHA!
Naturally, the endurance of my stock clutch concerned me since I had added over 100 lb-ft to the mix. Plenty of towing putting it through its paces, too. I upgraded to an RSR Clutch Kit by HS Tuning at around 34,000 miles. The RSR clutch uses a factory dual-mass flywheel and will hold 380 lb-ft, which is 100 lb-ft less than what was advertised when I bought it. I’d consider their RSR Hybrid Clutch Kit if I was shopping today. I think my driving style will remain relatively unchanged, except for a few on-ramp blasts and the occasional authoritative pass. 😉 If I’m wrong, then I may need some bail money and a good attorney!
Tires are the bond between the driveline and the pavement. As a result, anything that improves traction will improve the car’s ability to apply all of its newfound power to the pavement and to acceleration. The factory all-season tires compromise traction for longevity, especially during the winter. Using dedicated summer performance tires (or even some high performance all-season tires) makes a huge difference in the driving dynamic. I’ve tried and like the Firestone Firehawk Indy 500. It’s an excellent tire for the money. I also liked the Michelin Pilot Sport A/S3+ and their replacement, Michelin’s Pilot Sport All-Season 4. Both are more expensive than the Indy 500, but perform better and are suitable for year-round driving. Next, I may try the Michelin Pilot Sport 4S, which is a summer-only tire. Someone local to me says his 400+ horsepower GTI grips very well with them.
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Next, learn about the electronics upgrades that I’ve done…