Tyres and fuel economy ?

[jimgallaher]

Finally this weekend I got time to get 4 new tyres fitted, Falken 452's, replacing a set of re040's on front, and Autogrip f109's on rears, these tyres were on the car when I bought it. What a difference, cabin noise is much reduced, the car is so much more sure footed, I feel I can go hard into a corner now, previously the car felt like it was gonna let go in a spectacular fashion anytime I went too hard, even on a gradual bend. But enough of my wittering, my question is, now I've changed tyres my economy has dropped from 21-22mpg to 18-19mpg in one weekend, this is possibly due to the fact that I am driving the car harder than before, but do different tyres have differing mpgs ? I'm not complaining, just curious a 15 to 20% drop in economy is nothing when compared to the fun I'm now having with my new zed.

[Neilp]

They can do but nothing that dramatic. I'd check the tyre pressures. I really think it's u having fun with the happy pedal with all the extra grip though

[bronzee]

Tyre pressure can definitely have an effect on fuel economy.

[Chris`I]

As the others have said, check the tyre pressures - 35psi when cold. Some like them a little harder too, upto 37psi. If tyre pressures are fine, its your right foots fault I had no discernible difference in MPG changing my tyres from PS2s to Falkens on the 350z.

[bronzee]

Possibly too, your new tyres may have a marginally different rolling radius so that may throw the per mile, per what's used out even very marginally. Theory, but possible.

[dsapsfo1]

Always run 35psi all round on mine and noticed no difference in fuel economy in going from Bridgestones to Falkens.....

[350ash]

Different tyres can have a different rolling resistance which will affect fuel economy but I'd be surprised if it makes that much difference. I think cars like the Prius come with special economy tires which means that they have a very low rolling resistance but probably low grip levels as well.

[rtbiscuit]

Different tyres can have a different rolling resistance which will affect fuel economy but I'd be surprised if it makes that much difference. I think cars like the Prius come with special economy tires which means that they have a very low rolling resistance but probably low grip levels as well.

 

not grip, but a narrower tyre. if you put prius wheels on a zed then yes you would have less grip. but th ebiggest thing for economy is to run small narrow tyres,

 

compound and tread will play a part but the size of the wheel will have the biggest impact. the bigger the wheel the more power is needed to get it turning and to stop it. more power = Less MPG.

 

other methods are making the wheels lighter and also having a large surface area covering the wheel. bit like the bikes in the velodrome. to improve wind resistance round the wheel and reduce drag.