Difference between revisions of "Geo Setups"
hbaumhardt (talk | contribs) |
hbaumhardt (talk | contribs) |
||
| Line 79: | Line 79: | ||
</table> | </table> | ||
converting from mm to degrees; divide the toe in mm by the wheel rim diameter in mm then ARC SIN the answer | converting from mm to degrees; divide the toe in mm by the wheel rim diameter in mm then ARC SIN the answer | ||
| + | |||
| + | |||
| + | == Geo setting X does Y == | ||
| + | Some guidlines although its dependent on many, many other factors | ||
| + | Increasing front camber from the default -0.1° to -0.5° each side will dramatically improve the understeer although the inside edges of the tyres will wear slightly faster. | ||
| + | Increasing rear camber from the default -1.8° to -2.0° (or higher) makes the car more neutral after you've removed the understeer. | ||
| + | Front toe helps with the sharpness of the turn-in | ||
| + | Rear toe cancells out the rear suspension flex when the tyre is loaded which leads to toe out - so running more toe in compensates for that - you don't want toe out at the rear. | ||
== Setting your own geo == | == Setting your own geo == | ||
Revision as of 16:48, 24 August 2006
Some standard Geo settings
| Geometry | Standard S1 & S2 | S2 135R | 340R Road | 340R Track |
| Ride Height F/R | 130/130mm | 120/120mm | 100/1100mm | 100/1100mm |
| Steering axis inclination | 12° | 12° | 12° | 12° |
| Front Castor | +3.8° | +3.7° | +3.8° | +3.8° |
| Front Camber | -0.1° | 0° | -0.5° | -1.8° |
| Front alignment/toe | 0.2mm OUT Overall | 0 mm | 0.2mm OUT overall | 0.5mm OUT overall |
| Rear Camber | -1.8° | -1.8° | -2.0° | -2.7° |
| Rear alignment/toe | 1.2mm IN each side | 1.2mm IN each side | 1.5mm IN each side | 2.5mm IN each side |
| Bump Steer | 2.0° to 2.5° toe in |
converting from mm to degrees; divide the toe in mm by the wheel rim diameter in mm then ARC SIN the answer
Geo setting X does Y
Some guidlines although its dependent on many, many other factors Increasing front camber from the default -0.1° to -0.5° each side will dramatically improve the understeer although the inside edges of the tyres will wear slightly faster. Increasing rear camber from the default -1.8° to -2.0° (or higher) makes the car more neutral after you've removed the understeer. Front toe helps with the sharpness of the turn-in Rear toe cancells out the rear suspension flex when the tyre is loaded which leads to toe out - so running more toe in compensates for that - you don't want toe out at the rear.
Setting your own geo
Whilst a race prep specialist can charge £200 for a Geo you can DIY Castor, camber and toe settings.
1. To baseline your current setup www.alignmycar.co.uk will find a local place with a Hunter alignment system who will privide a setup sheet showing Castor, camber and toe for £15
If you dont have the S1 or S2 service manaual suspension sections you really should get them as this is only a small part; http://www.sandsmuseum.com/cars/elise/experience/maintenance/alignment/alignment.html
2. Set the front castor by "counting washers"
3. Set the front and rear camber by adding & removing shims (removing a 1mm shim plate will alter camber by approximately -0.25° at the front and -0.30° at the rear).
4. Back to the alignment centre to check your config for another £15 and set your front and rear toe for another £30. You can now alter the camber without materially affecting toe.