Wheel & Tyre Conversion Guide

Maximising Performance
Performance can be increased without the necessity of changing wheels, simply by selecting a tyre with a lower profile. This means maintaining the overall diameter by lowering the aspect ratio and increasing tyre width. Increases in tyre width are limited by the original wheel width.
 
Put simply, a tyre with a lower section height and wider tread has better cornering force and grip, thus improving steering stability. In order to attain the maximum performance from your vehicle, larger and wider wheels are recommended. Although high performance driving is our goal, there are certain safety guidelines that must be observed. This means that both wheel size, type and tyre height/width, must fall within certain limits. Every vehicle has set specifications.
 
The Inch-Up Approach to High Performance
Maximizing your car's performance by selecting a lower profile tyre or larger wheel size combination is referred to as "inching-up". Plus one or plus two tells you how much larger the wheel size is.
 
By fitting a larger wheel, increases in tyre section width are properly managed while correct overall diameter is maintained. This maximizes cornering force and grip without sacrificing any other handling parameters. In fact, all round performance is improved.
 
In order to fully maximize the full performance potential of a vehicle fitted with larger wheels and/or tyre section width it is recommended to uprate vehicle suspension as appropriate. Please contact our centre for information.
 
Please note that any change from original equipment fitment may effect vehicle ride and comfort.
 
Speed Symbols
Please note, the speed codes represented in this table reflect the speed capability of the vehicle and must also be considered in conjunction with the load index. Please ask for clarification.
 
SYMBOL Km/h Mph
S 180 113
T 190 118
U 200 124
H 210 130
1V 240 149
VR > 210 > 130
2W 270 168
3Y 300 186
ZR > 240 > 150

1 Tyres marked 'V' in conjunction with a load index, e.g. 93V are suitable for speeds in excess of 210 Km/h and up to 240 Km/h. (The load index given is for a speed of 210 Km/h and the load must be reduced by 3% for every increment of 10 Km/h up to 240 Km/h).

2 Tyres marked 'W' in conjunction with a load index, e.g. 83W are suitable for speeds in excess of 240 Km/h and up to 270 Km/h. (The load index given is for a speed of 240 Km/h and the load must be reduced by 5% for every increment of 10 Km/h up to 270 Km/h).

NB: Tyres marked with a 'W' speed symbol may incorporate 'ZR' in the size marking.

3 Tyres marked 'Y' in conjunction with a load index, e.g. 83Y are suitable for speeds in excess of 270 Km/h and up to 300 Km/h. (The load index given is for a speed of 270 Km/h and the load must be reduced by 5% for every increment of 10 Km/h up to 300 Km/h).

Tyres marked 'VR' within the size designation are designed for speeds in excess of 210 Km/h.

Tyres marked 'ZR' within the size designation are designed for speeds in excess of 240 Km/h.

 

To view the conversion charts click here


Superlite Wheels, 104 - 106 Tredworth Road, Gloucester. GL14QY. UK

Telephone: +44 (0) 1452 414465
Facsimile: +44 (0) 1452 308284
Email: karen@superlite-wheels.com

Copyright 1996-2003 Superlite