Porsche ® 991.2 Tubo S sets blistering quarter mile time of 9.78 seconds at 139.59 mph with new GIAC race gas map....


The Road Test Network has a long track record of testing a wide assortment of vehicles for their quarter mile acceleration capabilities. Over the last year they have put their latest in house acquisition, a 2018 Porsche 991.2 Turbos S, through a gauntlet of side by side comparisons with other makes and models, and have examined its performance improvement potential with basic after market upgrades. The Road Test Network has recorded impressive quartermile results in the process.

In its original form, without any after-market upgrades, the Porsche 991.2 TTS is formidable. On 93 octane at a density altitude of 1700 in Palm Beach, Florida, the vehicle pulled a best run of 10.617 at 128.10 MPH. For comparison, The Road Test Network later added the first upgrades of a Tubi exhaust and a performance chip. Champion Motorsport, one of the most respected names in the Porsche aftermarket, was tapped to upgrade the engine software program with a GIAC premium fuel calibration. Despite suboptimal conditions ( DA of 2100 ) on testing day, The Road Test Network's 911 Turbo S with upgrades flaunted strong performance improvements, shaving nearly half of a second and pushing another 6 mph. The best quarter mile run on that day was 10.177 seconds at 134.43 MPH.

Still wanting more power from the vehicle, The Road Test Network reached out to Champion and GIAC again, to explore custom tuning options with unleaded race gas ( a higher octane than the premium fuel found at most gas stations ). GIAC, which recently developed multi-map switching for the Continental SDI21 ECU family, created a race mode calibration for the 991.2 TTS. With extensive dyno testing and feedback from Champion Motorsport, the team at GIAC completed a race gas calibration that added 117 horsepower at the wheels, or 133 HP at the engine, over what the vehicle put out in its OEM configuration. These improvements in power resulted in significantly faster times and speeds at the track. With just the GIAC race tune, Tubi exhaust and racing fuel, the Road Test Network's 991.2 Turbo S ran a 9.97 second 137 MPH quarter mile at a less than ideal density altitude of 2200 in Palm Beach Florida. Following concerns that traction issues might be holding the car back, the Road Test Network team upgraded the OEM tires to Toyo R888s and further improved their quarter mile to a 9.78 second 139.59 MPH result at a slightly better DA of 1500.

To date this is the fastest quarter mile time and speed posted publicly for a Porsche 991.2 TTS with so few modifications. Special thanks to The Road Test Network and Champion Motorsport, for all their testing of and feedback on these GIAC DME calibrations.

Video Of Quartermile Runs

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Quarter Mile Comparison Chart.

Vehicle ConfigurationETTrap SpeedDensity Altitude
Stock baseline10.617128.10 MPH1700
GIAC pump
Tubi Exhaust
OEM tires
10.177134.43 MPH2100
Tubi Exhaust
OEM tires
9.97137.00 MPH2200
Tubi Exhaust
R888 tires
9.78139.59 MPH1500