Transmission talk

Jon Lawson

What trends can be identified in gearbox and differential technology? Jon Lawson gets the thoughts of one Tier 1 industry insider.

The OEM car market might be stealing all the limelight when it comes to the public perception of new powertrains, but Tier 1 suppliers are also working hard to improve products and take advantage of new technological developments.

This is particularly so when it comes to automotive transmissions. One company that occupies a unique space in the sector is RT Quaife Engineering, as it supplies gearboxes, shafts and diffs to a diverse range of customers from entry-level club motorsport competitors all the way up to OEM clients including Ford and Lotus. Other OEMs could also soon become customers as discussions are ongoing behind-the-scenes.

The company was founded by Rod Quaife in 1965 and initially manufactured close-ratio five speed conversions for Norton and Triumph motorbikes. He worked in a small shed in Penshurst, Kent, southeast England. Success came quickly, and within five years there were class victories at the Isle of Man TT and at the Daytona speedway. By the 1970s, the company had diversified and became involved with the car market.

Ben Ashton is a manager at the firm, which now has two manufacturing sites totalling over 50,000 square feet in Gillingham and near Sevenoaks, Kent. Citing recent examples of where technology is accelerating development, he says, “We are always looking at ways to make our manufacturing processes more efficient, either to reduce costs or to increase productivity. We employ a combination of CAD, real-life testing and third-party simulation analysis. We are currently developing one of our gearboxes, looking to reduce the noise. We have invested in a development car so we can carry out testing on the road and on track, we have set up a small dyno so we can bench test the gearbox after each change, and are working with transmission analysis specialists to highlight any areas that need improvement.

He continues: “We use 3D modelling software in our design office, and have made use of sub-contractors for the occasional rapid prototyping requirements we have. For example, for our recently developed sequential gearbox for the Mk3 Focus RS and ST, we had two 3D printed casting patterns made for the transmission case so we could build the development gearboxes sooner and without the capital investment in production patterns for castings. This allowed us to have a test gearbox in our development car with a spare gearbox that we could use to make changes to as required during development, ready to swap into the car straight away after removing the gearbox that was already in it.”

Right weight champion

Pondering the compromises of design, Ashton continues, “With gearboxes, we need to strike a balance between strength of the gears and the rotating mass. Lighter weight gears will make for a better performing gearbox in terms of gear shifts, as they can change their rotational speed faster, but to achieve a lower weight material will need to be lost, which can reduce the strength of the gear and therefore reduce the power they can transmit.”

The vast majority of the firm’s gears are manufactured from specific grades of steel alloys, where the intended application will govern the precise composition. There are however occasionally unusual requests for more exotic materials, like titanium or lithium aluminium for customer-specific products.

When analysing the motorsport market, Ashton observes, “The advancement in the ECUs being used has changed dramatically over the last 5 years. They are not only becoming more affordable, but also far more advanced. More and more aftermarket ECUs are now capable of flat shift strategies which in turn extends the life of the gearbox.”

Quaife offers sensors for gear position and oil temperature on some of its gearboxes.

Like many in the segment, the company is keen to take advantage of electrification. “The rise in EVs has meant an increased demand for quiet transmissions,” notes Ashton. “Historically, transmission noise has never been the primary concern in motorsport, however, with the EV market growing and Quaife Engineering receiving more and more enquiries from our motorsport and automotive customers for quieter transmission solutions, we have been working tirelessly with our R&D team to develop quieter gear sets so that we can apply this knowledge to all of our new developments, opening up the EV transmission market to us.”