Tyre Profile Vs.Ride Quality and F.E

[gemithomas]

I've always wanted to know what the Tyre profile has to do with Ride quality and F.E. Also what would be its effect on Handling of the vehicle.

Is it like Tyre profile in directly proportional to ride quality and inversely proportional to F.E and Handling?!!.

Another question would be would changing the tyre profile affect the suspension in the long run.

[hydrashok]

Lesser profile = better handling, harsher ride, better looks.

I don't think tyre-profile as such has anything to do with FE.

The lower profile tyres have stronger sidewalls that don't flex during hard cornering. This translates into better handling. The difference is really perceptible.

I don't think lower-profile tyres will affect the suspension, if the tyre-upsizing is done as per formula, keeping the rolling radius the same. However, the slightly increased stress put on the suspension (due to the harsher ride-conditions) may speed-up wear and tear somewhat. Just a common-sense assessment. Don't know this for a fact

[aah78]

lower profile tyres are also more susceptible to aquaplane in the wet - a larger contact patch with the road.

the wider contact patch, however, increases your traction which leads to a drop in fuel efficiency.

as hydrashok says, lower profile tyres will translate to better handling but bad roads lead to a harsh ride which has an adverse effect on suspension in the long run.

they're great for showing off! mega rims and low profile tyres is a popular bling-factor combination.

the tyres your car comes with from the factory are generally selected after extensive tests to attain that "perfect" balance of handling, economy, ride comfort, etc.

[gemithomas]

Originally Posted by aah78

lower profile tyres are also more susceptible to aquaplane in the wet - a larger contact patch with the road.
.

what does that really mean. what is aquaplane

[vid6639]

aqua planing occurs when your driving on wet roads. If the road has a lot of water and the tyre is not capable of displacing the water then a thin film of water is formed between the tyre and the road. When this happens you lose grip as the tyre is not in contact with the road. this is extremely dangerous and a wider tyre is more susceptible to this.

[gemithomas]

ok. The Ford fusion has got 195/60 R15 tyres. I think that is one of the major factors that is spoiling its ride comfort expecially at low speeds. Will there be any difference if i change ot 155/75 R15. If not what would be the appropriate size without affecting the speedometer

[rohan_fonseca]

Wouldn't low profile tires would lead to a decrease in pickup due to higher weight of the rim and greater contact patch? Broader tyres on a light car would increase the chances of auaplaning as well?

[razor4077]

Originally Posted by gemithomas

ok. The Ford fusion has got 195/60 R15 tyres. I think that is one of the major factors that is spoiling its ride comfort expecially at low speeds. Will there be any difference if i change ot 155/75 R15. If not what would be the appropriate size without affecting the speedometer

Speedo will not be affected much by the change in size... BUT...

I would seriously suggest that you do not consider downsizing to 155 from 195!
155 is the width of a stock Santro tyre. Apart from the fact that it will look quite ridiculous on your Fusion, your handling (wet/dry/whatever) and braking will go for a toss too! Furthermore, this would require you to change your rims from the stock ones to thinner ones to accomodate the new tyres.
A Ford Fusion was not designed for tyres that thin. Period.
Haven't come across a case of downsizing from OE before this

To improve your ride, I would suggest you invest in some quality rubber which are designed keeping road comfort in mind. An example would be the Michelin Engery XM1, a tyre that is quite popular on this forum. You'll be surprised at the difference a better tyre can make to the ride (and handling).
You could also consider getting yourself alloy wheels (dunno if you already have them). The reduced unsprung weight (alloys are much lighter than the steel rims) helps the ride factor.