tyre size increased

[z4newbie2021]

Hi well i changed my assorted tyres out for Michelin pilot sports and there is a big difference in the handling.
I increased the size from 225 40 r18 to 225 45 r18 and 255 35 t18 to 255 40 r 18.
They fit fine the ride and road noise is much better really pleased.
Included pictures with the first ones with the h r lowered suspension i had put back to standard last week.

 

[z4newbie2021]

I just drove to work and gave the car a bit of a workout i could not be more pleased.
The grip is good the handling is a lot less twitchy.
Its very stable through bumpy corners and uneven roads.
The ride is brilliant its not soft but quiet and compliant and comfortable it still feels like a sports car.
I found this site really helpful with speed readings and fit ect.
https://www.tacomaworld.com/tirecalc?tires=225-40r18-225-45r18
All in all very pleased i changed the size it gave me a sidewall increase of about 1 cm or 10 % the speedo reads about 3% slow so 31 instead of 30 i can live with that.
A big thank you to everyone who gave me advice before i did the change.

 

[mmm-five]

So you've:

• Replaced 4 random tyres of unknown quality/vintage with 4 good, new tyres
• Increased the profile
• Replaced the suspension

I'd suggest it's not just the higher profile that's giving you all the benefits you're feeling

 

[z4newbie2021]

I know what you mean the ride improved immensely when i put the new suspension on. Its now a whole new level of better and that would have happened with new tyres the same size but the side wall increase is helping and it gave the car 10mm more road clearance which is nice.

So you've:

• Replaced 4 random tyres of unknown quality/vintage with 4 good, new tyres
• Increased the profile
• Replaced the suspension

I'd suggest it's not just the higher profile that's giving you all the benefits you're feeling

 

[brillomaster]

sounds like you're one happy customer! glad to hear you're enjoying the car more and more

 

[z4newbie2021]

sounds like you're one happy customer! glad to hear you're enjoying the car more and more

LoL i am a lot happier now i was not happy the first day i took it to work and it scraped ever single speedbump on the way in thirteenin total. The handling was very squirmy the new shocks and springs sorted most of it out and the tyres made a huge difference i am going to replace the pads and discs this weekend to sort the lack of bite breaking and hopefully i wont have to throw any more money at it for a while thanks for the reply

 

[rawpilot]

Interesting. Good to hear that mod improves the comfort.
Definitely something I'd like to try, but it's going to take quite some time for me to wear my current Michelins down enough to justify changing them

 

[DaveD]

I’ve done this too. I think it makes a meaningful difference to rough road dynamics. Less tramlining and takes the edge off square Also looks good as well IMO!

 

[Nicolae]

Hello, I am looking to give this a try, just waiting for my alloys to come, didn't bought the tires yet. Do you think this is going to fit a z4 2010 with adaptive suspension? What pressure do you go for? I am asking this as i do believe that the suspension goes like 10mm down when in sport plus... Anyone can give bit of advice? Much appreciated

 

[z4newbie2021]

I’ve done this too. I think it makes a meaningful difference to rough road dynamics. Less tramlining and takes the edge off square Also looks good as well IMO!

I am very happy with this set up.
Looking at your car i now want black wheels it's just lovely.
Thank you for the reply

 

[z4newbie2021]

Hello, I am looking to give this a try, just waiting for my alloys to come, didn't bought the tires yet. Do you think this is going to fit a z4 2010 with adaptive suspension? What pressure do you go for? I am asking this as i do believe that the suspension goes like 10mm down when in sport plus... Anyone can give bit of advice? Much appreciated

sorry i am no qualified to answer that i have just gotten my z4 and am learning something new every day. But there will be someone on here that will know

 

[True-Blue]

Hello, I am looking to give this a try, just waiting for my alloys to come, didn't bought the tires yet. Do you think this is going to fit a z4 2010 with adaptive suspension? What pressure do you go for? I am asking this as i do believe that the suspension goes like 10mm down when in sport plus... Anyone can give bit of advice? Much appreciated

There’s loads of information in the E89 part of the forum on what works and what doesn’t

 

[Nicolae]

Could not see anything that suggests what working or no on a non M z but with adaptive suspension. A link will be much appreciated if I did miss anything