To further enhance the power and performance of our Jetta, Matt Ford (the “MF” in MF Automotive) used a KermaWare Q Loader to flash our engine ECU with a tune programmed to give us more torque and horsepower. After downloading our original factory tune to the Q Loader, it is emailed to Kerma TDI, where a custom tune is written and e-mailed back and then installed in the car with the Q Loader. We received a low-smoke tune, as well as a modified tune, for our engine. When we drove the car on the stock tune, it seemed as if the new Stage 1 Colt camshaft gave us a very modest bump in low rpm performance, but when the tunes were installed, the car really woke up—with a significant boost in torque and horsepower that could be felt from the driver’s seat.
After the work was complete and we put a few hundred miles on the car, we took it back up to Bean’s Diesel Performance and strapped it back down to the dyno to confirm our driving impressions. With the Stage 1 Colt Cams camshaft and the stock tune in the ECU, we saw peak horsepower increase from 102.1, with 174 lb/ft of torque, to a peak of 108.9 hp and 186 lb/ft of torque, with more power and torque on demand from 2,350 rpm to about 4,000 rpm. That translates to a 6.7 percent improvement in horsepower and a 6.9 percent boost in torque.
Dyno testing with both of the Kerma TDI tunes showed huge gains in torque, with as much as 56 lb/ft improvement from 2,500 rpm to 3,000 rpm, with as much as a 32-hp improvement over our baseline performance on the modified tune with a max of 122.4 hp and 224 lb/ft of torque. This is an improvement of nearly 30 percent in torque and nearly 20 percent horsepower—and even more in the lower rpm range, where you really feel it on the street. The low smoke tune actually produced slightly more peak horsepower, with 122.8 hp measured, along with a peak of 214 lb/ft of torque. From about 3,200 rpm and up, both tunes were very similar in power and torque measurements, but from 2,000 to 3,200 rpm, the modified tune solidly outperformed the low smoke tune by as much as 14 lb/ft of torque and 8 hp. Incidentally, both tunes produced similar amounts of smoke, (a lot more than the factory tune) at wide-open throttle and low rpm but cleaned up decently as boost built.
This is in the November issue of Diesel World magazine.