BMW M4 Geometry FRS Fast Road Setup
Aside from being certified in Chassis Dynamics by Prodrive and Optimum G, our actual hands-on experience of improving the speed and enjoyment of Motorsport and high-performance road cars spans decades!
In our opinion, making a car faster and more enjoyable through twisting roads or around a race track requires the driver to have absolute confidence in the car in order to exploit it’s full potential. Confidence can only be acquired when the vehicle behaves in a way that is linear so that the driver can predict it’s reactions to up-coming events.
There are many facets to the subject of Chassis Dynamics, and they are all as important as each other, but the primary objectives are to achieve front/rear (tyre) grip balance for neutral handling, and exploiting the tyre contact patch for maximum grip. Everything on the chassis leads to these two points. For more in-depth analysis of Chassis Dynamics we have written a couple of white papers on this topic here and here.
We don’t know what the original geometry settings design briefs were for any of the cars that we see, but we do know that they’re not optimal. It could be that fuel economy or tyre life is the priority, but it wouldn’t surprise us at all if it’s the case that little of no consideration at all is given to geometry optimisation considering that premium brand vehicles such as McLaren, Ferrari, Lamborghini, Aston Martin all benefit significantly from some expert attention!
BMW M4 Geometry FRS Fast Road Setup:
The BMW M4 is a mighty fine car, however it can be improved. This car is a beautiful example being only a few months old with and with 6000 miles under her belt. In standard form the main complaints was boiled down to becoming unstable during chassis disturbances such as pot-holes and full-throttle gear shifting, and a feeling of car-sickness when in comfort mode. Upon initial road testing our Master Tech confirmed that and also fed back poor chassis balance.
The fist test we do is to check that the frame is square and the tyre circumferences are equal. An “out of square” frame can make the car travel like a crab, and uneven tryes across an axle having a limited slip differential will make the LSD operational when it shouldn’t be, causing it to be pushed (rwd) or pulled (fwd) to one side in a straight line when accelerating. We see this a lot!
However this M4 was perfect in this respect, so we set about optimising the geometry settings to the objections stated above. The end result with just three hours of work is nothing short of transformative with now having zero disturbance-rejection, near-perfect grip-balance and increased traction at full throttle. In the words of the owner/driver the following day:
“ Back from TDI-plc.com where it underwent a thorough geometry analysis and had the AC Schnitzer springs fitted. The handling and ride have been transformed. What was once a spiteful handing car now has the road and ride manners you’d expect. No more does it try and throw me off of the road and no longer does it badly manage deflections or make me car sick when the dampers are set to comfort. It tracks true and straight under acceleration and when changing gear. Poor road surfaces are handled beautifully and as a result, cornering and braking are both vastly improved.”
Job well done and money well spent.
If you would like information on BMW M4 Geometry FRS Fast Road Setup or improving the performance of any car, please contact us.