GIVING US THE SLIP
Why carmakers are banishing the electronic nannies to the back seat
Case in point, Ford. "We try and get the fun-to-drive factor, which means the driver can destabilise the car if he wants," Len Urwin, powertrain engineering manager at Ford's Team RS, told us. "10 years ago, you couldn't do lift-off oversteer in a Ford because it was construed as being not want the customer wanted. It was seen as unsafe, but these days for performance cars, to a degree it's encouraged."
It was a statement that gladdened our hearts and got us looking for more examples of this liberated attitude. The glaring one is the Toyota GT86.
"Discreet safety net"
Elsewhere Porsche is subtlety promoting tail out action in its new Cayman, pointing out that the PDK twin-clutch gearbox "permits a dynamic driving style" by figuring out the driver is drifting and holding onto gears when the stablilty control is switched off, "assuming a suitably protected roadway".
Of course, in the old days, loss of grip threatened whether you went looking for it or not. But for the enthusiast driving right on the edge of grip on road or track was infinitely rewarding, not least because it was usually telegraphed so clearly.
"If the grip started to go you could really feel it," celebrated Jaguar test driver Norman Dewis told us recently. "If you look at these cars today, the grip they've got ... These really wide tyres really glue them to the road."
new Exige S.
The Lotus race setting
The beautifully balanced V6 two-seater has a version of Lotus's Dynamic Performance Management co-created with Bosch that now offers four different levels of assistance, with the addition of a Race setting just above 'off'. Lotus calls it an 'enhancement' to its traditionalhandling purity.
"We want the car to be able to communicate to the driver, give them enough feedback so they can feel the limit of that grip, and when they reach it, that's when our stability system comes in," principal vehicle dynamics engineer Alan Clark tells PistonHeads.
"It comes to the point of a certain yaw angle and we say, okay, we need to act here and help the driver out," says Clark.
You'd think the EU would step in this point and wave the red flag, and to an extent it does. From this year all new cars sold in Europe have to be fitted with stability control, but the rules also allow the system to be switched off, providing a light indicates that fact and that when you start the car next time, it reverts to the stability 'on' setting. It's a measure of how discreet Lotus's Race setting is that the EU requires it to trigger the 'off' dash light...
It's not the Lotus way, but a limited-slip diff is often touted as the perfect ingredient to for fast, tail-dancing driving, especially a torque-sensing LSD such as that in the GT86.
"You can steer the car by sliding on the throttle, which many people like," says Heinrich Huchtkoetter, senior engineer for drivetrain engineering firm GKN.
The British firm makes the Visco LokLSDs fitted to the last generation BMW M cars, and Huchkoetter reveals that the M division has long wanted its cars to be driftable. He says, "When BMW first approached us, they asked: 'can do you a limited-slip differential which enables a driver who can do it to keep the vehicle in a constant drift?'"
Drivers found it tricky to balance though, and our engineering insider explains that's because the speed sensing Visco Lok will only lock up when it detects a spinning wheel. "There is a delay, so you had to give more throttle to speed up."
But again we've got technology to help us out. The M5, M6 and forthcoming M3 come with the so-called Active Mdifferential, also made by GKN. The independent control of each driveshaft this gives has a wealth of advantages, including drifting. "You can close the LSD even before the inner wheel is spinning, then you get it more or less controlled by the throttle into a drift immediately," Huchkoetter tells us.
This tech is spreading too. Jaguar's active electronic differential on the XFR-S and the top-spec F-Type is the same system, made by GKN. It can apply "full locking torque almost instantaneously" says Jaguar - ideal for a tail wag.
Even Lotus, not a fan of passive LSDs, is keen. "An active diff would be a better compromise than a mechanical limited-slip diff," says Clark. Plotting one on the new Esprit maybe...?