If you look into your vehicle documentation, you will surely find the tyre sizes recommended by the manufacturer. When selecting tyres you should definitely take them into account. However, as there is a wide range of products available on the market today, you can choose the size that best suits your needs.
Some drivers decide to change the width of the tyre profile for aesthetic reasons while others want to make a difference in terms of driving comfort.
f you want to find out which tyre replacements you can use for your car, please use our size calculator.
The tyre profile, commonly referred to as model height, is the distance from the end of the rim to the edge of the tyre. It is also one of the formats that determine the tyre size (the others are the width and diameter of the rim).
All the attributes that make up the size are related, which means that if you want to change one of the parameters for a given car, you have to adjust the other parameters as well. You need to do so in order to maintain the total wheel diameter (wheel height) provided by the car manufacturer.
How do I calculate a tyre profile?
A low-profile tyre is a model where the side height from rim to road is relatively small in relation to its section width. The tyre profile is not an absolute value - it is a combination of width and height instead.
Example: In the size 205/55 R16 the number 55 is otherwise 55% of 205.
According to the formula, the sidewall height of a 205/55 R16 tyre will be less than 225/55 R16. In the second example, the overall diameter (total tyre height) will also be automatically higher.
What are low profile tyres?
A low-profile tyre is a model where the side height from rim to road is relatively small in relation to its cross-section width. Low profile tyres are usually used as original equipment in medium and higher class vehicles, especially in sports cars with greater performance. They are also popular with car tuning fans who take advantage of the possibility to enlarge the rim (this makes the vehicle look more sporty).
Over the years, the concept of "low profile" has changed its meaning, or rather the dimensions that are included in this concept. Back in the 1970s every model with a profile below 80 was treated as small. Nowadays the dimension 55 is no longer considered as low.
The 205/55 R16 is now one of the most popular tyre sizes in Europe. It is widely used for mid-range cars and often installed without a rim protection rank, making it no longer considered a low profile size.
There is a direct relation between height and width. The 185/55 R15 models whose actual sidewall height is much lower than the 205/55 R16 are much easier to consider as low profile tyres. We may consider 55-50 series or less to be low profile tyres, depending on the width. They are usually equipped with a protective rim edge.
What are the lowest series values for low profile tyres?
The ETRTO (European Tyre & Felicity Manufacturers) Standards from 2009 define as the lowest series of 20, namely size 375/20 R21. However, during the North American Sema trade show, Nexen and Kumho showed the world's first 15 series tyres.
In the case of Nexen, it is the N3000 model size 365/15 ZR 24, while Kumho presented the Ecsta SPT KU31 size 385/15 ZR 22.
Low profile tyres - advantages
A low profile is often associated with the use of larger tyre width and rims and this can positively affect the behaviour of the car on a dry surface when braking and cornering.
The low side also means more stiffness, which is a particularly valuable feature in the case of dynamic driving on winding roads.
Low profile tyres also provide better "contact with the car" as the driver has more control over the car and is able to better predict its behaviour. Side tilts are also much less noticeable. But still the most visible advantage of using low profile tyres is a better visual appeal of the vehicle.
The Kumho Ecsta is an example of a very low profile tyre.
Low profile tyres give the car a better look - when combined with a large-diameter rim, the vehicle gets a more sporty character.
However, one of the most important advantages of using low profile tyres is their behaviour when cornering. They give a sense of stability to the vehicle compared to tyres with a high profile.
“Unfortunately, the driving comfort is noticeably reduced when using such tyres. They dampen noise and vibrations to a lesser extent and special care must be taken when driving on uneven roads.”
Technical Department Manager
Low profile tyres - disadvantages
The pressure in low profile tyres can’t be too low because the tyres become more susceptible to damage of any kind.
When you have low profile tyres installed, be especially careful when crossing the curb. Doing it carelessly can damage the chassis components.
Also, there is a higher risk of damage to aluminum rims, and the protective edge of low profile tyres will not save you from damage if you fall into the hole on the road.
Another factor that also accelerates wear and tear is the driving style of the driver and the nature of the vehicles on which they are used. Tyres of this type are often fitted on sports cars where the manufacturer, in order to meet the customer expectations, focuses on a high level of adhesion and this is at the expense of faster wear.
The chassis and suspension of the vehicle must be properly adapted to larger rims and tyres, which are less likely to amortize unevenness. Otherwise, low profile tyres will cause all suspension components to wear fast.
In addition, if the wheel height is changed by 5 mm, an adjustment of the vehicle light settings will be required.