Difference between revisions of "Geo Setups"
| Line 10: | Line 10: | ||
<td class=xl25 width=125 style='width:94pt'>340R Track</td> | <td class=xl25 width=125 style='width:94pt'>340R Track</td> | ||
<td class=xl25 width=125 style='width:94pt'>Exige S1</td> | <td class=xl25 width=125 style='width:94pt'>Exige S1</td> | ||
| + | <td class=xl25 width=125 style='width:94pt'>Msport</td> | ||
</tr> | </tr> | ||
<tr height=17 style='height:12.75pt'> | <tr height=17 style='height:12.75pt'> | ||
| Line 18: | Line 19: | ||
<td class=xl27>100/110mm</td> | <td class=xl27>100/110mm</td> | ||
<td class=xl27>112/122mm</td> | <td class=xl27>112/122mm</td> | ||
| + | <td class=xl27>100/110mm</td> | ||
</tr> | </tr> | ||
<tr height=17 style='height:12.75pt'> | <tr height=17 style='height:12.75pt'> | ||
| Line 25: | Line 27: | ||
<td class=xl27>12°</td> | <td class=xl27>12°</td> | ||
<td class=xl27>12°</td> | <td class=xl27>12°</td> | ||
| + | <td class=x127>12°</td> | ||
<td class=x127>12°</td> | <td class=x127>12°</td> | ||
</tr> | </tr> | ||
| Line 31: | Line 34: | ||
<td class=xl27 x:str="'+3.8°">+3.8°</td> | <td class=xl27 x:str="'+3.8°">+3.8°</td> | ||
<td class=xl27 x:str="'+3.7°">+3.7°</td> | <td class=xl27 x:str="'+3.7°">+3.7°</td> | ||
| + | <td class=xl27 x:str="'+3.8°">+3.8°</td> | ||
<td class=xl27 x:str="'+3.8°">+3.8°</td> | <td class=xl27 x:str="'+3.8°">+3.8°</td> | ||
<td class=xl27 x:str="'+3.8°">+3.8°</td> | <td class=xl27 x:str="'+3.8°">+3.8°</td> | ||
| Line 44: | Line 48: | ||
style='mso-spacerun:yes'> </span></span></td> | style='mso-spacerun:yes'> </span></span></td> | ||
<td class=xl27 x:str="'-0.5°">-0.1°</td> | <td class=xl27 x:str="'-0.5°">-0.1°</td> | ||
| + | <td class=xl27 x:str="'0.3°">-0.3°</td> | ||
</tr> | </tr> | ||
<tr height=17 style='height:12.75pt'> | <tr height=17 style='height:12.75pt'> | ||
| Line 52: | Line 57: | ||
<td class=xl27>0.5mm OUT overall</td> | <td class=xl27>0.5mm OUT overall</td> | ||
<td class=xl27>0.1mm OUT overall</td> | <td class=xl27>0.1mm OUT overall</td> | ||
| + | <td class=xl27>0.2mm OUT overall</td> | ||
</tr> | </tr> | ||
<tr height=17 style='height:12.75pt'> | <tr height=17 style='height:12.75pt'> | ||
| Line 62: | Line 68: | ||
style='mso-spacerun:yes'> </span></span></td> | style='mso-spacerun:yes'> </span></span></td> | ||
<td class=xl27 x:str="'-2.4° "><span lang=EN-GB>-2.7°<span | <td class=xl27 x:str="'-2.4° "><span lang=EN-GB>-2.7°<span | ||
| + | style='mso-spacerun:yes'> </span></span></td> | ||
| + | <td class=xl27 x:str="'-2.4° "><span lang=EN-GB>-2.0°<span | ||
style='mso-spacerun:yes'> </span></span></td> | style='mso-spacerun:yes'> </span></span></td> | ||
</tr> | </tr> | ||
| Line 70: | Line 78: | ||
<td class=xl27>1.5mm IN each side</td> | <td class=xl27>1.5mm IN each side</td> | ||
<td class=xl27>2.5mm IN each side</td> | <td class=xl27>2.5mm IN each side</td> | ||
| + | <td class=xl27>1.2mm IN each side</td> | ||
<td class=xl27>1.2mm IN each side</td> | <td class=xl27>1.2mm IN each side</td> | ||
</tr> | </tr> | ||
Revision as of 08:48, 5 September 2006
Some standard Geo settings
| Geometry | Standard S1 & S2 | S2 135R | 340R Road | 340R Track | Exige S1 | Msport |
| Ride Height F/R | 130/130mm | 120/120mm | 100/110mm | 100/110mm | 112/122mm | 100/110mm |
| Steering axis inclination | 12° | 12° | 12° | 12° | 12° | 12° |
| Front Castor | +3.8° | +3.7° | +3.8° | +3.8° | +3.8° | +3.8° |
| Front Camber | -0.1° | 0° | -0.5° | -1.8° | -0.1° | -0.3° |
| Front alignment/toe | 0.2mm OUT Overall | 0 mm | 0.2mm OUT overall | 0.5mm OUT overall | 0.1mm OUT overall | 0.2mm OUT overall |
| Rear Camber | -1.8° | -1.8° | -2.0° | -2.7° | -2.7° | -2.0° |
| Rear alignment/toe | 1.2mm IN each side | 1.2mm IN each side | 1.5mm IN each side | 2.5mm IN each side | 1.2mm IN each side | 1.2mm 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.
Increasing front toe helps with the sharpness of the turn-in
Increasing 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 provide a setup sheet showing castor, camber and toe for £15
2. If you dont have the S1 or S2 service manual 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
3. Set the front castor by "shuffeling washers" on the top wishbone pivots.
4. 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).
5. You could set the toe yourself, but since a quarter turn of the track rod alters toe by 2mm its a damned delicate affair without a real time readout.
6. 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.
MEMO: Someone else can explain how to create a DIY geo rig and set bump steer !