Lotus Exige V6 Dynamic Performance Management (DPM)

Lotus introduced their cutting-edge Dynamic Performance Management (DPM) system with the launch of the Exige V6 in 2012. Developed jointly with Bosch it was immediately one of the most advanced systems of its kind.

Lotus DPM uses a combination of 3 key systems that work together – ABS, TC and VDC.

ABS is the anti-lock braking system that is able to use all four brakes independently to perform minor miracles in terms of car stability.

TC is commonly described as Traction Control but is more accurately described as ‘Torque Control’.

VDC stands for Vehicle Dynamic Control and uses a yaw sensor placed in the middle of the car to measure slip angles at both the front and the rear axles. This information is then combined with steering angle data to measure understeer and oversteer. The Lotus DPM switch allows the driver to choose the way these three key systems are combined.

TOUR Mode makes full use of all of the car’s electronic systems and takes a zero tolerance approach to both understeer and oversteer. As soon as slip is detected at either axle by the VDC, the system cuts the fly-by-wire throttle to zero and applies whichever combination of the brakes is required to bring the car to a halt along your chosen steering trajectory. You can barrel into a hairpin, throw in ludicrous amounts of steering lock and stamp fully on the throttle. You can also come sharply off the throttle mid-corner, apply the brakes, left foot brake and the car will simply refuse to spin and will not even require any corrective lock. It just brings the car smartly to a halt, however much the tyres protest. TOUR is the only mode that features Understeer Recognition. However, ‘Understeer Eradication’ might be a better term. The system has been torture tested to cope with every conceivable challenge the road can throw at it, including an ECU’s nightmare of a mixture sheet ice for two wheels, dry tarmac for the others and the car has to pull-up in a straight line. It’s strictly ‘pass’ or ‘fail’ too with Bosch’s own very stringent testing standards.

  • ABS: Constant
  • Max Engine RPM: 6800rpm
  • Throttle progression: Standard
  • Engine Protection Valve (Exhaust valve) strategy: EPV opens at high throttle/RPM applications
  • DPM Characteristics: Understeer recognition on, managed slip threshold
SPORT Mode allows both oversteer and understeer up to a set threshold measured by the VDC’s yaw sensor. In practice, it’s not a very large angle of oversteer, no more than a quarter turn of opposite lock and the intervention is very obvious and not at all subtle. When the system decides it’s time to release the pent-up torque, it does so with a mighty surge. SPORT will allow the car to understeer which actually has its benefits. It’s useful for learning when you’re asking too much of the front tyres and you get more feedback from the car about your driving, which means you can still learn about how the car reacts to your inputs. It’s a great option to have and still offers a good safety net, allowing you to feel some under and oversteer without any risk of a spin. In the event of a big mistake the car will just pull up sharply in front of you rather than pirouette off into the distance.

  • ABS: Constant
  • Max Engine RPM: 7200rpm
  • Throttle progression: Increased response
  • Engine Protection Valve (Exhaust valve) strategy: EPV opens from medium throttle applications/engine speeds
  • DPM Characteristics: Understeer recognition switched off. Increased slip thresholds and increased yaw angle available
RACE Mode (only available with the Race Pack) is a Torque Control system, designed to minimize oversteer and optimise traction when entering and exiting corners and should only be used on track. The goal is to find the maximum traction possible for any given set of tyres and track surface, on any given day. It does this by ‘learning’ the amount of grip available. Unlike TOUR and SPORT modes that are based on fixed slip thresholds (beyond which they cut the available torque to zero), RACE manages the slip thresholds using a feedback loop between the car’s sensors. This is where it gets a bit technical, when you plant your foot on the exit of a corner, the VDC estimates the grip available and allows a best guess amount of torque. If the car begins to oversteer it then reduces the allowed torque and this process continues in a loop until the allowed torque matches the available grip. At this point you have maximum possible traction. The learning process takes one clear intervention, that is, one oversteer moment at one corner, not a whole lap. But this learning process will need to be re-done at the beginning of each new session on track. The key thing to understand is that the system starts from a maximum yaw angle and torque threshold. In other words, you’re likely to experience a moment of oversteer while it learns. Thereafter, it will continue to minimize oversteer for the remainder of the session on track. In a car as responsive as an Exige, quick reactions will be needed to catch the slide, so RACE is best left to more experienced drivers. Once up to speed, the ability to adapt means that it works in both the wet and the dry and also with any combination of track surface and make of tyre. Even today, very few Torque Control systems are able to do this. The other major plus of this system is how smoothly it operates. Interventions are notably smoother than the other modes where torque is cut back to zero. With RACE mode, excess power just bleeds away, like the deftest ease back from a pro racer’s right foot. It’s really subtle and seamless in operation and any weight transfer fore and aft is supremely well managed as a result.

  • ABS: Constant
  • Max Engine RPM: 7200rpm
  • Throttle progression: As Sport
  • Engine Protection Valve (Exhaust valve) strategy: EPV permanently open
  • DPM Characteristics: Understeer recognition switched off. VDC intervention level set high to allow race traction control to function. The traction system learns and calculates available levels of grip and optimises the correct level of torque intervention to deliver maximum traction
OFF is for the purists, which will always be the best choice for those who want to use their track time to learn about the car and improve their driving skill. In this mode all assists are turned off except those related to braking.

  • ABS: Constant
  • Max Engine RPM: 7200rpm
  • Throttle progression: As Sport
  • Engine Protection Valve (Exhaust valve) strategy: EVP permanently open
  • DPM Characteristics: TC and VDC is completely switched off
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