215x35x18 good idea or not?

[cheechy]

Thanks mate, It'll look even better once I get the Votex fitted ?

ahem I believe you

Get the finger out ☝

 

[sciroccorrado]

If you want reasonable mpg do not ever think about 18"s. They may look nice but you will loose at least 12mpg from 15" and 8mpg from the se wheels you have. I found the torque steer ridiculous too and only felt extra grip on smooth roads. I would avoid the 17" for the same reason. Look good but expensive on fuel, tyres and bent wheels too.

I would challenge this observation as a little bit ott. If you have a look at the difference between Baby Boomer (16") and JRV (18") I only lost about 1mpg - and that was over a number of fills. I agree with the theory, but the results don't show that.

 

[ICowie]

I would challenge this observation as a little bit ott. If you have a look at the difference between Baby Boomer (16") and JRV (18") I only lost about 1mpg - and that was over a number of fills. I agree with the theory, but the results don't show that.

I'd have to agree with you there, On my Tdi the mpg went down slightly on the DIS by around 7-8mpg but I had it mapped the same week I fitted the wheels so it's hard to say for sure what made the bigger difference (Probably a lot to do with me pressing the loud pedal a bit more than usual)

If you go by what you pay at the pump and the distance you're covering I'd say there's very little difference. I recently managed to go from Kirkcaldy, Scotland down to Stanley. County Durham and back which is roughly a 300ml round trip for around £20-£25 of diesel despite the DIS telling me I was getting just over 50mpg.

 

[oko]

I would challenge this observation as a little bit ott. If you have a look at the difference between Baby Boomer (16") and JRV (18") I only lost about 1mpg - and that was over a number of fills. I agree with the theory, but the results don't show that.

Interesting Jeremy, keep up your fuelly work, wonder what you will find longer term.
I have not analysed my data but will do when(if) time allows. From memory I bought my 2002 AMF new and reckon averaged 60-65 mpg on 15" (175's) wheels. Then 120k miles later bought a two year old ATL 90 at 22k. It had the 17" sport wheels and I only averaged 53ish. So some months later I decided to swap the wheels between the two and found I was back in the mid 60's just like that. 220k later with MYP and remap Im in the
mid 70's ! When I replaced my AMF (wife's on 180k) with a white ATL on 100k and 18" I only got 46mpg (as much as I tried), then bought your winter 15"steels with 195's(thank you), and getting 54ish (short trips).

It would be interesting to hear from others who have experimented with wheel/tyre sizes. I believe it is the most important factor on our A2's fuel consumption after the engine type (and driving style and road type/distance which tend to be fairly constant per driver)

Another disadvantage of 18" wheels is likelyhood of a back injury! Has anyone else noticed torque steer being a problem ? Unless the ET dimension is spot on for the car, I expect the ackerman angle to be wrong and more noticable than it would with narrow wheel/tyres.
Ask any keen cyclist whether they would prefer skinny or wide tyres on a long fast ride, I would love 18" wheels if they were made with a 5J width; wonder if BMW i3 wheels can be fitted ?

Martin