Digi-Tec MINI Cooper And Cooper S
An Added Sparkle That Goes Beyond Just Being Faster
One of the most extreme and well-sorted BMW M Coupes I've ever driven came from Digi-Tec, a chip tuning specialist in Datteln, Germany. Thus, it comes as no surprise that the latest additions to Digi-Tec project lineup are the new MINI Cooper and Cooper S. The Cooper S is obviously more amenable to big power increases, but the Digi-Tec Cooper shows a worthwhile boost as well.
Digi-Tec's managing director, Michael Pollmuller, is a very accomplished track driver himself and is one of the few tuning firm owners who competes against the professional drivers in the annual Sport Auto Tuner GP.
Michael's experience with vehicle dynamics means if you're prepared to spend the money to achieve that overall balance, you can be sure of a tuned car that handles and stops as well as it goes.
Digi-Tec is well aware of the mechanical limits of the cars it tunes, and the limited torque capacity of the new MINI gearboxes was high on the list of things to watch for during the ECU re-mapping program.
"We were aware of the gearbox limitations," Michael explained, "and so we did not increase torque a great deal. Instead, we aimed to improve low-end response and concentrated on bringing the peak torque down in the rev band."
Running on a maximum boost pressure of 0.8 bar, the factory-fresh supercharged 1.6-liter motor produces 163 bhp at 6000 rpm and 155 lb-ft (210 Nm) of torque at 4000 rpm. Modifications include a forged steel crankshaft, stronger main bearings and harder valve seats. The oil sump capacity is greater, as some lubricant is contained within the oil/water-cooling matrix, and an internal oil spray system cools the undersides of the pistons. These modifications prepare the engine for a long and reliable life with forced aspiration, and with the ease of tuning such an engine in mind, BMW made sure there was plenty in reserve.
Digi-Tec's Cooper S uses 0.93 bar of boost to produce 197 bhp (200 PS) at 6750 rpm with a healthy 183 lb-ft (248 Nm) of torque at 3500 rpm. But even with the enhanced power, sixth gear is simply too tall to achieve top speed. The motor will run to 7000 rpm in fifth gear, which equates to a 10-mph increase in top speed to 145 mph; 0 to 62 mph takes 7.0 sec., 0.4 sec. faster than standard. As a measure of in-gear punch, 50 to 75 mph now takes 7.9 sec. in fifth gear, 0.8 sec. faster.
Mechanical work includes a smaller pulley to make the supercharger spin faster, while the ECU is reprogrammed to add more fuel on full throttle to both feed and cool the motor.