New tyres and fuel consumption

[philthy]

I agree, tyre pressures could be way out. You are right, tyre fitters get some weird ideas.

but

F=ma
When you are spinning the wheel with your finger, how fast are you accelerating the wheel? ie: push it slowly & it's quite easy, now try & push it really fast.

I'm not just talking theory on this. My latest wheel tyre combo is 2kg heavier & in variable speed traffic it has really hit my economy. If I can maintain aconstant speed on the run home, I can manage <6L/100 but if it's varying between 60-120 then I'm up near 7L/100. It's also taken the edge off my acceleration.

Haha... fair enough.. I may just have to take some time out to have a crack at doing the calcs in a bit more detail when I'm supposed to be working tomorrow.

[noone]

My TT's are 25 pounds a piece. Brutal... But they look good

[instigator]

i'm searching for light tyres that provide enough grip.
i know potenza's are verry good in grip levels, but they have a hard tyrewall on the side wich makes them heavy.
not ideal foy Superleggera's :-s

there are many things that have influence on the car etc, with only tyres.
thats why searching it out is not easy, not much info can be fund on these things.
my best fuel economy is 5.0L/100Km with my GTI with the use of cruise control and constant speed.

[brad]

Have a look at ContiSportContact3. The sidewalls are quite thin. All the others are about the same weight AFAIK.

or, go down to the tyre shop with some scales

[kangfu]

Im definitely noticing a difference going from the stock 16" wheels and 205/45/16 Toyo T1-R tyres, to 17" wheels with 215/40/17 Bridgestone RE001's.

MUCH better grip though, the extra width puts power down much better i feel. Out of corners ESP isnt going off at me like a nutter anymore.

Prefer it, even with the slightly higher fuel economy.