New automatic ZF transmission has successful motorsport debut

ZF automatic transmission for motorsportA new automatic ZF transmission supplied to the BMW235i Racing Cup has had a successful race debut on the legendary Nürburgring in Germany.

The 8P45R motorsport transmission is a lighter and more dynamic improvement on the 8HP predecessor which has been fitted onto this class of BMW race cars since the 2014 season.

When it was first introduced, the automatic transmission was treated with suspicion by drivers and pit crews. After a successful testing programme through the season the superior performance and better safety features have impressed drivers and spectators.

The 8HP transmission eases the driver’s workload allowing them to stay completely focussed on their environment.

The risk of making driver shift error is reduced dramatically, which in turn reduces the risk of mechanical damage. The risk of fatal blockages are also minimised as is the risk of shocks delivered to the driven axle which can be catastrophic.

In developing this new automatic transmission, ZF has committed to producing a transmission purely for the motorsports market. Previously the manufacturer has modified a standard production unit for use in racing vehicles.

By choosing this production path ZF has had more freedom to optimise ratios, shift points and shift speed without having to compromise.

The designers have also managed to shave off 15 percent of the transmissions overall weight and also managed to cut internal power loss.

The new 8P45R transmission is notable for its omission of a torque converter. The all-important racing launch is instead implemented by internal shift elements.

The gear ratio spacing has also been reduced so whereas previously the 8HP transmission only used six gears across a standard operating range, the new transmission uses all eight during normal operation.

Dirk Adorf, chief instructor of the BMW Motorsport junior program, was positive after trying the new transmission.

He said: “I am truly fascinated by the performance of ZF´s engineers after my first laps with the new gearbox. Being an automotive technician myself, I wouldn´t have thought it possible to build an automatic transmission without a torque converter, that provides such a fast changing of the gears as well as easy and comfortable starting.

“The clutch elements are extremely fine-tuned. I am sure that this system will be an example for other racing gearboxes and even for the development of series transmissions.”

ZF plans for the transmission to be commercially available in the second quarter of 2016. Initially, the 8P45R will only be available for BMW M235i Racing cars.

ZF’s commitment to engineering at the highest levels is symptomatic of their commitment to quality and feeds back through all levels of their work.