| Car suspension tuning is a very subtle and difficult black art. It's all about what's happening dynamically in response to transient inputs (go around a corner, hit a bump, etc.). I believe Lotus does a lot of engineering consulting helping other manufacturers dial in suspensions. I wouldn't be surprised if Tesla had them consult. Even some of the big car companies have trouble dialing in suspension on their own (I'm looking at you underdamped Japanese cars). European brands tend to be really good at this, and can take the same raw materials that everyone else is working with and create superior setups. Porsche somehow manages to start with the 911 where they stick the engine way out behind the rear axle (high polar moment of inertia, poor front/rear weight distribution) and make it handle beautifully. VW cars also tend to have great suspension tuning. Being able to keep the weight low to the ground in the Tesla contributes to a low center of gravity and I imagine must really help enormously. Also the body under-tray is beautiful, like something you'd expect to see on a purpose built race car, probably helps a lot with the aerodynamics. I imagine more and more cars will get similar under-trays to improve aerodynamics and fuel efficiency. It's interesting there is strong anti-dive geometry built into the car, probably to avoid problems with throttle lift oversteer caused by inexperienced drivers. I wonder if the current Model S handling leaves anything to be desired when driven to it's absolute limits and how the car would handle with some of the anti-dive geometry removed. Removing this geometry is a common mod on some cars. |
Actually there are some benefits to the arrangement. The high polar moment of inertia actually should make any spin slower to start and easier to catch than a mid engine arrangement. Under hard braking the weight shifts forwards so the weight distribution changes to more balanced than with other arrangements. Under power the weight is over the rear wheels for power out of the corner.
A 911 behaves differently to other cars but I'm not sure the arrangement is actually worse in most dynamic scenarios. Understeer into the corners is the main dynamic weakness when pushed really hard and can be compensated for by trail braking into the corners. I guess you can get into trouble if you go into a corner too fast, panic brake and lose the rear end but if you are used to the set up you can make use of it.
[I've only driven a 1980's 911 so maybe I'm over extrapolating to all rear engined cars and I've never tried a mid engined car. This book is really good at explaining how do get the most out of different weight distributions and has some fun stories (I've got the first edition but it probably isn't much different): http://www.amazon.co.uk/Porsche-High-performance-Driving-Han...]