Geo Setups: Difference between revisions

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== Some standard Geo settings ==
== Standard Setups ==


<table x:str border=0 cellpadding=0 cellspacing=0 width=655 style='border-collapse:
===Elise/Exige===
collapse;table-layout:fixed;width:493pt'>
 
<tr height=17 style='height:12.75pt'>
{| border=1 cellpadding=5 align=center
  <td height=17 class=xl24 width=158 style='height:12.75pt;width:119pt'>Geometry</td>
|- style="background-color:#fed200; face:bold;"
  <td class=xl25 width=122 style='width:92pt'>Standard S1 &amp; S2</td>
| rowspan=2 | Geometry || rowspan=2 | Ride Height<br />Front/Rear || colspan=3 align=center | Front || colspan=2 align=center | Rear
  <td class=xl25 width=125 style='width:94pt'>S2 135R</td>
|- style="background-color:#fed200;"
  <td class=xl25 width=125 style='width:94pt'>340R Road</td>
| Castor || Camber || Toe [Degrees] || Camber || Toe [Degrees]
  <td class=xl25 width=125 style='width:94pt'>340R Track</td>
|-
</tr>
| Standard S1      || 140/140mm || +3.8° || -0.1° || 0.2mm OUT Overall [-0.03°] || -1.8° || 1.2mm IN each side [0.16°]
<tr height=17 style='height:12.75pt'>
|-
  <td height=17 class=xl26 style='height:12.75pt'>Ride Height F/R</td>
| Standard S2     || 130/130mm || +3.8° || -0.1° || 0.2mm OUT Overall [-0.03°] || -1.8° || 1.2mm IN each side [0.16°]
  <td class=xl27>130/130mm</td>
|-
  <td class=xl27>120/120mm</td>
| S2 135R         || 120/120mm || +3.7° || 0°    || 0mm [0.00°]              || -1.8° || 1.2mm IN each side [0.16°]
  <td class=xl27>100/110mm</td>
|-
  <td class=xl27>100/110mm</td>
| 340R Road       || 100/110mm || +3.8° || -0.5° || 0.2mm OUT Overall [-0.03°] || -2.0° || 1.5mm IN each side [0.20°]
</tr>
|-
<tr height=17 style='height:12.75pt'>
| 340R Track       || 100/110mm || +3.8° || -1.8° || 0.5mm OUT Overall [-0.07°]|| -2.7° || 2.5mm IN each side [0.33°]
  <td height=17 class=xl26 style='height:12.75pt'>Steering axis inclination</td>
|-
  <td class=xl27>12°</td>
| Exige S1        || 112/122mm || +3.8° || -0.5° || 0.1mm OUT Overall [-0.01°]|| -2.4° || 1.2mm IN each side [0.16°]
  <td class=xl27>12°</td>
|-
  <td class=xl27>12°</td>
| Exige S2        || 130/130mm || +3.8° || -0.3° || 0mm [0.00°]              || -1.8° || 1.5mm IN each side [0.20°]
  <td class=xl27>12°</td>
|-
</tr>
| Exige 240R      || 120/120mm || +3.8° || -0.3° || 0mm [0.00°]              || -1.8° || 1.5mm IN each side [0.20°]
<tr height=17 style='height:12.75pt'>
|-
  <td height=17 class=xl26 style='height:12.75pt'>Front Castor</td>
| 111R            || 130/130mm || +3.8° || -0.1° || 0mm [0.00°]              || -1.8° || 1.2mm IN each side [0.16°]
  <td class=xl27 x:str="'+3.8°">+3.8°</td>
|-
  <td class=xl27 x:str="'+3.7°">+3.7°</td>
| 211              || 100/110mm || +4.0° || -1.4° || 0mm [0.00°]              || -2.5° || 1.2mm IN each side [0.16°]
  <td class=xl27 x:str="'+3.8°">+3.8°</td>
|-
  <td class=xl27 x:str="'+3.8°">+3.8°</td>
| Msport          || 100/110mm || +3.8° || -0.3° || 0.2mm OUT Overall [-0.03°] || -2.0° || 1.2mm IN each side [0.16°]
</tr>
|-style="background-color:#fed200;"
<tr height=17 style='height:12.75pt'>
| colspan=7 | Non-Standard Geo Settings
  <td height=17 class=xl26 style='height:12.75pt'>Front Camber</td>
|-
  <td class=xl27 x:str="'-0.1°">-0.1°</td>
| a forum hero S2 race || 110/115mm || +3.6° || -2.0° || 0.5 mm OUT each side [-0.07°] || -3.0° || 1 mm IN each side [0.13°]
  <td class=xl27>0°</td>
|}
  <td class=xl27 x:str="-0.5° "><span lang=EN-GB>-0.5°<span
 
  style='mso-spacerun:yes'> </span></span></td>
The standard settings are used when car is loaded with 2x75kg passengers and half tank of fuel.
  <td class=xl27 x:str="'-1.8° "><span lang=EN-GB>-1.8°<span
 
  style='mso-spacerun:yes'> </span></span></td>
 
</tr>
=== Exige V6 (2012 onwards) — Lotus factory geometry ===
<tr height=17 style='height:12.75pt'>
 
  <td height=17 class=xl26 style='height:12.75pt'>Front alignment/toe</td>
Factory specifications from Lotus Service Notes, Section TDV, pages 8–11, updated 17 August 2022.
  <td class=xl27 x:str="'0.2mm OUT Overall">0.2mm OUT Overall</td>
 
  <td class=xl27>0 mm</td>
All toe figures are TOTAL TOE across the axle, not toe per wheel. Negative toe = toe-out; positive toe = toe-in.
  <td class=xl27>0.2mm OUT overall</td>
 
  <td class=xl27>0.5mm OUT overall</td>
Geometry must be checked at mid-laden ride height, with two 75 kg occupants (or equivalent ballast), a FULL fuel tank and correct tyre pressures. Measure ride height from the ground to the chassis side rails at the marked jacking points.
</tr>
 
<tr height=17 style='height:12.75pt'>
{| class="wikitable"
  <td height=17 class=xl26 style='height:12.75pt'>Rear Camber</td>
! Model
  <td class=xl27 x:str="'-1.8°">-1.8°</td>
! Ride height F/R
  <td class=xl27 x:str="'-1.8°">-1.8°</td>
! Front caster
  <td class=xl27 x:str="'-2.0° "><span lang=EN-GB>-2.0°<span
! Front camber
  style='mso-spacerun:yes'> </span></span></td>
! Front total toe
  <td class=xl27 x:str="'-2.7° "><span lang=EN-GB>-2.7°<span
! Rear camber
  style='mso-spacerun:yes'> </span></span></td>
! Rear total toe
</tr>
|-
<tr height=17 style='height:12.75pt'>
| Exige S Coupe/Roadster
  <td height=17 class=xl26 style='height:12.75pt'>Rear alignment/toe</td>
| 125/136 mm
  <td class=xl27 x:str="'1.2mm IN Overall">1.2mm IN each side</td>
| +3.2°
   <td class=xl27>1.2mm IN each side</td>
| -0.4°
  <td class=xl27>1.5mm IN each side</td>
| -0.06° OUT
  <td class=xl27>2.5mm IN each side</td>
| -1.90°
</tr>
| +0.60° IN
<tr height=17 style='height:12.75pt'>
|-
  <td height=17 class=xl26 style='height:12.75pt'>Bump Steer</td>
| Sport 350 (Pirelli P-Corsa)
  <td class=xl27></td>
| 130/136 mm
  <td class=xl27>2.0° to 2.5° toe in</td>
| +2.8°
  <td class=xl28></td>
| -0.2°
  <td class=xl27></td>
| -0.12° OUT
</tr>
| -2.10°
<tr height=0 style='display:none'>
| +0.60° IN
  <td width=158 style='width:119pt'></td>
|-
  <td width=122 style='width:92pt'></td>
| Sport 350 (Michelin Pilot Sport 4)
  <td width=125 style='width:94pt'></td>
| 130/136 mm
  <td width=125 style='width:94pt'></td>
| +2.8°
  <td width=125 style='width:94pt'></td>
| -0.8°
</tr>
| +0.14° IN
</table>
| -2.10°
converting from mm to degrees; divide the toe in mm by the wheel rim diameter in mm then ARC SIN the answer
| +0.80° IN
|-
| Sport 380 (Michelin Pilot Sport Cup 2)
| 130/136 mm
| +2.8°
| -0.8°
| -0.12° OUT
| -2.10°
| +0.60° IN
|-
| Cup 380
| 130/136 mm
| +2.8°
| -0.8°
| -0.12° OUT
| -2.10°
| +0.60° IN
|-
| Sport 410 / Sport 420 / Cup 430
| 130/136 mm
| +2.8°
| -0.8°
| -0.12° OUT
| -2.10°
| +0.60° IN
|}
 
==== Factory geometry tolerances ====
 
{| class="wikitable"
! Model group
! Front caster
! Front camber
! Front total toe
! Rear camber
! Rear total toe
|-
| Exige S
| ±0.2°
| ±0.1°
| ±0.03°
| ±0.15°
| ±0.03°
|-
| Sport 350 (Pirelli or Michelin)
| ±0.2°
| ±0.1°
| ±0.06°
| ±0.10°
| ±0.08°
|-
| Sport 380 (Michelin Cup 2) / Cup 380
| ±0.2°
| ±0.1°
| ±0.06°
| ±0.10°
| ±0.08°
|-
| Sport 410 / Sport 420 / Cup 430
| ±0.3°
| ±0.1°
| +0.06° / -0.02°
| ±0.10°
| +0.02° / -0.08°
|}
 
==== Tyre pressures for geometry preparation ====
 
{| class="wikitable"
! Model / tyre configuration
! Front cold
! Rear cold
|-
| Exige S / early Sport 350 (Pirelli P-Corsa)
| 2.2 bar (31.9 psi)
| 2.6 bar (38.0 psi)
|-
| Later Sport 350 / Sport 390 (Michelin Pilot Sport 4)
| 2.0 bar (29 psi)
| 2.2 bar (32 psi)
|-
| Sport 380 / Cup 380 / Sport 410/420 / Cup 430 (Michelin Pilot Sport Cup 2)
| 2.0 bar (29 psi)
| 2.2 bar (32 psi)
|}
 
'''Important:''' Lotus lists the Exige Sport 390 in the tyre specifications, but does not expressly list it in the geometry tables in this revision of Section TDV. Its geometry should be verified against the applicable Lotus service information before being represented as a factory specification.
 
'''Source:''' Lotus Service Notes — ''Exige V6 Models 2012 Model Year Onwards, Technical Data — Vehicle, Section TDV''. Geometry and ride heights: pages 8–11 (updated 17 August 2022). Tyre pressures: page 6 (updated 26 February 2021).
    
 
===Evora===
 
{| border=1 cellpadding=5 align=center
|- style="background-color:#fed200; face:bold;"
| rowspan=2 | Geometry || rowspan=2 | Ride Height<br />Front/Rear || colspan=3 align=center | Front || colspan=2 align=center | Rear
|- style="background-color:#fed200;"
| Castor || Camber || Toe || Camber || Toe
|-
| Standard || 125/147mm || +5.2° || -0.3° || 0mm || -1.6° || 1.5mm IN each side
|-
|}
 
 
Converting toe from mm to degrees:
 
# Measure the rim diameter in mm as the size e.g. 17" is not the actual diameter your measurements are based on.
# Multiply the result by PI to get the circumference.
# Divide the result by 360 to get mm per degree.
# Divide the toe mm by the mm/degree result to get toe in decimal degrees
 
 
Or Excel =DEGREES( ASIN( TOE_IN_MM / ( RIM_DIA_INCHES * 25.4 )))
 
Or use the calculator on this page, hypotenuse is the rim diameter the toe  per wheel (total toe divided by 2) in mm is width (or toe in degrees is angle A). * http://joyfulcoder.net/sohcahtoa/


== Geo setting X does Y ==
== Geo setting X does Y ==
Some guidlines although its dependent on many, many other factors
Some starter guidelines although its really really complex stuff and dependent on 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 past -1.0° is great for high speed corners but can compromise low speed cornering, will reduce braking effectiveness and it will tramline on the road.


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 under steer with front camber. Look at the ratios on the standard settings and maintain the front/rear % delta.


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 affects stability or responsiveness of turn in. Front Toe out (standard) makes the car more responsive turn in but causes additional drag in straights. Front toe in is more stable in straight line.


Increasing front toe helps with the sharpness of the turn-in
* Rear Toe controls the stability of the rear through the corner. Rear toe in (standard) makes the car more stable and apparently the Elise toes in more at the rear as the suspension compresses. Rear toe out causes the rear to steer out from the corner, reducing stability.


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.
== Factors affecting Geo ==
When asking questions on the forums about "the best geo for ..." the following need to be considered so make an effort to specify;
 
* What you are using the car for (road, sprint race, endurance race)
* Tyre spec (section & compound)
* Spring rates
* Damper spec and settings
* Ride height
* Current Geo settings
* Perceived problems with current setup


== Setting your own geo ==
== Setting your own geo ==
Whilst a race prep specialist can charge £200 for a Geo you can DIY castor, camber and toe settings.
Whilst a race prep specialist can charge £200 for a Geo you can DIY castor, camber and toe settings. With a lot of variability in quality at alignment centres (and Lotus dealers !) for the best results put the effort in yourself and build a string based alignment rig which can be more accurate than a computerised laser system. To make a DIY geo/alignment rig see:[[Geo Alignment Rig (Home Made)]]
 


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
1. The Hunter computerised laser alignment system is one of the best (the variability is quality of the operator) http://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 (probably in dd:mm:ss rather than decimal degrees) for £15 and can set the front and rear toe for another £30.


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.
2. If you are going to DIY you must have the relevant S1 or S2 service manual suspension sections. Setting castor and camber is straightforward as a caster washer and camber shim have fixed values, whereas toe is delicate - which way do you wind the flats and a quarter turn of the track rod can alter the toe by 2mm (e.g. just tightening the locknuts).


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.
'''Absolutely critical to getting a good geo is having the right ballast in the seats e.g. for a 780Kg race Elise the difference between empty and an 85Kg driver is 5mm ride height, 0.2° camber and 1mm toe. (Depending on Spring rates used) Don't let your alignment place guess'''


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.
==See Also==
* http://arc.seloc.org/viewthread.php?tid=52913 - The pole & string thread by Randy
* http://arc.seloc.org/viewthread.php?tid=49382
* http://arc.seloc.org/viewthread.php?tid=106461
* http://forums.pelicanparts.com/porsche-911-technical-forum/581498-stringless-wheel-alignment-diyers.html


MEMO: Someone else can explain how to create a DIY geo rig and set bump steer !
[[Category:Suspension]]
[[Category:Lotus Elise]]
[[Category:S1]]
[[Category:S2]]
[[Category:Lotus 2-Eleven]]
[[Category:S2 Exige]]
[[Category:Lotus Europa]]
[[Category:Lotus Evora]]
[[Category:VX220]]
[[Category:Lotus Exige V6]]

Latest revision as of 17:46, 17 October 2026

Standard Setups

Elise/Exige

Geometry Ride Height
Front/Rear
Front Rear
Castor Camber Toe [Degrees] Camber Toe [Degrees]
Standard S1 140/140mm +3.8° -0.1° 0.2mm OUT Overall [-0.03°] -1.8° 1.2mm IN each side [0.16°]
Standard S2 130/130mm +3.8° -0.1° 0.2mm OUT Overall [-0.03°] -1.8° 1.2mm IN each side [0.16°]
S2 135R 120/120mm +3.7° 0° 0mm [0.00°] -1.8° 1.2mm IN each side [0.16°]
340R Road 100/110mm +3.8° -0.5° 0.2mm OUT Overall [-0.03°] -2.0° 1.5mm IN each side [0.20°]
340R Track 100/110mm +3.8° -1.8° 0.5mm OUT Overall [-0.07°] -2.7° 2.5mm IN each side [0.33°]
Exige S1 112/122mm +3.8° -0.5° 0.1mm OUT Overall [-0.01°] -2.4° 1.2mm IN each side [0.16°]
Exige S2 130/130mm +3.8° -0.3° 0mm [0.00°] -1.8° 1.5mm IN each side [0.20°]
Exige 240R 120/120mm +3.8° -0.3° 0mm [0.00°] -1.8° 1.5mm IN each side [0.20°]
111R 130/130mm +3.8° -0.1° 0mm [0.00°] -1.8° 1.2mm IN each side [0.16°]
211 100/110mm +4.0° -1.4° 0mm [0.00°] -2.5° 1.2mm IN each side [0.16°]
Msport 100/110mm +3.8° -0.3° 0.2mm OUT Overall [-0.03°] -2.0° 1.2mm IN each side [0.16°]
Non-Standard Geo Settings
a forum hero S2 race 110/115mm +3.6° -2.0° 0.5 mm OUT each side [-0.07°] -3.0° 1 mm IN each side [0.13°]

The standard settings are used when car is loaded with 2x75kg passengers and half tank of fuel.


Exige V6 (2012 onwards) — Lotus factory geometry

Factory specifications from Lotus Service Notes, Section TDV, pages 8–11, updated 17 August 2022.

All toe figures are TOTAL TOE across the axle, not toe per wheel. Negative toe = toe-out; positive toe = toe-in.

Geometry must be checked at mid-laden ride height, with two 75 kg occupants (or equivalent ballast), a FULL fuel tank and correct tyre pressures. Measure ride height from the ground to the chassis side rails at the marked jacking points.

Model Ride height F/R Front caster Front camber Front total toe Rear camber Rear total toe
Exige S Coupe/Roadster 125/136 mm +3.2° -0.4° -0.06° OUT -1.90° +0.60° IN
Sport 350 (Pirelli P-Corsa) 130/136 mm +2.8° -0.2° -0.12° OUT -2.10° +0.60° IN
Sport 350 (Michelin Pilot Sport 4) 130/136 mm +2.8° -0.8° +0.14° IN -2.10° +0.80° IN
Sport 380 (Michelin Pilot Sport Cup 2) 130/136 mm +2.8° -0.8° -0.12° OUT -2.10° +0.60° IN
Cup 380 130/136 mm +2.8° -0.8° -0.12° OUT -2.10° +0.60° IN
Sport 410 / Sport 420 / Cup 430 130/136 mm +2.8° -0.8° -0.12° OUT -2.10° +0.60° IN

Factory geometry tolerances

Model group Front caster Front camber Front total toe Rear camber Rear total toe
Exige S ±0.2° ±0.1° ±0.03° ±0.15° ±0.03°
Sport 350 (Pirelli or Michelin) ±0.2° ±0.1° ±0.06° ±0.10° ±0.08°
Sport 380 (Michelin Cup 2) / Cup 380 ±0.2° ±0.1° ±0.06° ±0.10° ±0.08°
Sport 410 / Sport 420 / Cup 430 ±0.3° ±0.1° +0.06° / -0.02° ±0.10° +0.02° / -0.08°

Tyre pressures for geometry preparation

Model / tyre configuration Front cold Rear cold
Exige S / early Sport 350 (Pirelli P-Corsa) 2.2 bar (31.9 psi) 2.6 bar (38.0 psi)
Later Sport 350 / Sport 390 (Michelin Pilot Sport 4) 2.0 bar (29 psi) 2.2 bar (32 psi)
Sport 380 / Cup 380 / Sport 410/420 / Cup 430 (Michelin Pilot Sport Cup 2) 2.0 bar (29 psi) 2.2 bar (32 psi)

Important: Lotus lists the Exige Sport 390 in the tyre specifications, but does not expressly list it in the geometry tables in this revision of Section TDV. Its geometry should be verified against the applicable Lotus service information before being represented as a factory specification.

Source: Lotus Service Notes — Exige V6 Models 2012 Model Year Onwards, Technical Data — Vehicle, Section TDV. Geometry and ride heights: pages 8–11 (updated 17 August 2022). Tyre pressures: page 6 (updated 26 February 2021).


Evora

Geometry Ride Height
Front/Rear
Front Rear
Castor Camber Toe Camber Toe
Standard 125/147mm +5.2° -0.3° 0mm -1.6° 1.5mm IN each side


Converting toe from mm to degrees:

  1. Measure the rim diameter in mm as the size e.g. 17" is not the actual diameter your measurements are based on.
  2. Multiply the result by PI to get the circumference.
  3. Divide the result by 360 to get mm per degree.
  4. Divide the toe mm by the mm/degree result to get toe in decimal degrees


Or Excel =DEGREES( ASIN( TOE_IN_MM / ( RIM_DIA_INCHES * 25.4 )))


Or use the calculator on this page, hypotenuse is the rim diameter the toe per wheel (total toe divided by 2) in mm is width (or toe in degrees is angle A). * http://joyfulcoder.net/sohcahtoa/

Geo setting X does Y

Some starter guidelines although its really really complex stuff and dependent on 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 past -1.0° is great for high speed corners but can compromise low speed cornering, will reduce braking effectiveness and it will tramline on the road.
  • Increasing rear camber from the default -1.8° to -2.0° (or higher) makes the car more neutral after you've removed the under steer with front camber. Look at the ratios on the standard settings and maintain the front/rear % delta.
  • Front toe affects stability or responsiveness of turn in. Front Toe out (standard) makes the car more responsive turn in but causes additional drag in straights. Front toe in is more stable in straight line.
  • Rear Toe controls the stability of the rear through the corner. Rear toe in (standard) makes the car more stable and apparently the Elise toes in more at the rear as the suspension compresses. Rear toe out causes the rear to steer out from the corner, reducing stability.

Factors affecting Geo

When asking questions on the forums about "the best geo for ..." the following need to be considered so make an effort to specify;

  • What you are using the car for (road, sprint race, endurance race)
  • Tyre spec (section & compound)
  • Spring rates
  • Damper spec and settings
  • Ride height
  • Current Geo settings
  • Perceived problems with current setup

Setting your own geo

Whilst a race prep specialist can charge £200 for a Geo you can DIY castor, camber and toe settings. With a lot of variability in quality at alignment centres (and Lotus dealers !) for the best results put the effort in yourself and build a string based alignment rig which can be more accurate than a computerised laser system. To make a DIY geo/alignment rig see:Geo Alignment Rig (Home Made)


1. The Hunter computerised laser alignment system is one of the best (the variability is quality of the operator) http://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 (probably in dd:mm:ss rather than decimal degrees) for £15 and can set the front and rear toe for another £30.


2. If you are going to DIY you must have the relevant S1 or S2 service manual suspension sections. Setting castor and camber is straightforward as a caster washer and camber shim have fixed values, whereas toe is delicate - which way do you wind the flats and a quarter turn of the track rod can alter the toe by 2mm (e.g. just tightening the locknuts).


Absolutely critical to getting a good geo is having the right ballast in the seats e.g. for a 780Kg race Elise the difference between empty and an 85Kg driver is 5mm ride height, 0.2° camber and 1mm toe. (Depending on Spring rates used) Don't let your alignment place guess

See Also