Lotus Elise: Peal on Brakes

From: Pgpeal@aol.com
Subject: Elise rotors and Impact info
Date: Fri, 13 Sep 1996 18:50:24 -0400

I'm sure the Elise rotors are all MMC - no ferrous backing plate in there at all. The Discovery Channel programme covers the brake system very fully.

If I remember from the press release I wrote, the MMC brakes are lighter (lower unsprung weight), and hence can be made bigger diameter. The bigger diameter obviates the need for a servo (better braking torque for lighter clamping load), and also helps to deliver a good handbrake.

The MMC material dissipates heat quicker than ferrous materials do, which keeps brake temperatures low. The acknowledged brake-killer is the Stelvio Pass in Italy - just one run down the steep and tortuous series of hairpin bends is enough to cook virtually any production car disc-pad combination, with surface temperatures of 700 degrees C+ being recorded. The Elise MMC discs, even after numerous runs, didn't exceed 350 degrees C. I really believe that this material is maybe the biggest breakthrough of the all the technologies in Elise - reasonably easy to introduce to mainstream models in the near future.

As to the reason for the Impact, it's quite simple - the Impact team hired a guy from Lotus on a long contract to play a major part in (lead, even?) the chassis development team. He also drove the car in the land speed record runs (for a while, Lotus had two employees with land speed records to their name - the other for a sub-500 kg electric vehicle in the UK), hence the Lotus decal on the car.

The engineer's name is Clive Roberts, and he's still resident in Detroit. Lotus enthusiasts have experienced his work already - before he joined Lotus, he was Caterham's chassis whiz, and sorted the De Dion rear suspension. On joining Lotus, he helped Roger Becker and John Miles sort the original M100 chassis. He knows what he's doing!

Good night, all!