Can l change tyre profile size...?

Peter Peter

Registered User
Does it look any different?
I don't know yet, had them fitted this evening..
When I had that mix 245 with 235 ones, the car was bit shaking when I was driving from 80mph, but that could be of few reasons ; I might have shocker damaged after massive bang into a pothole, or alignment went off. So they fitted and balanced new two 245 ones and removed rear 245 ones, which I got last week and rebalanced them too... All nice 0:00 balanced.
Total I paid for tyres : 2x used tyres with 6.5 tread total with shipping £95 and 2x brand new ones for £140 becuse couldn't get same brand used ones.
And I paid £55 for fitting only becuse I used 3 different fitting places.. I know crazy .. First, they charged me £25 for removing tyres and fitting 2x 245s last week.
Next day I had to go other fitter, as I tried to air all tyres at tesco pump but i couldn't remove metal valve cap on one old tyre. I purchased metal caps from aliexpress so they got all rusty. So he had to remove the wheel and flattened tyre to remove and replace new valve that cost me £10 and today fitting two new tyres and balancing all 4 £20 So total I paid £290 .... rip off..
Tyre prices went up.. every business now making excuses of corona ... And fitting went up too
In summer 2019 I purchased 4x 235 brand new ones for £200 of ebay and fitting was only £30 all 4. If the fkin roads would be repaired i would save 300 bucks :shrug::sorry:
 

AlS3BE

Registered User
Next day I had to go other fitter, as I tried to air all tyres at tesco pump but i couldn't remove metal valve cap on one old tyre. I purchased metal caps from aliexpress so they got all rusty.

The problem with metal valve caps is the different metals used in the valve is different to the metal caps and the metal start corroding at different rates and fuse together somehow. Even expensive ones do this.
Had fancy looking caps in my younger days. Never again. Good old black plastic ones are fine.
 

Rjw76

Registered User
If you change the aspect ratio of your tyres you will directly affect your gearing by changing the rolling radius. Going from 35 - 40 % aspect ratio (not width !!! this is NOTHING to do with your wheel size!) will increase your rolling radius therefore lower your gear ratio, whilst for your mother this may not be a bad thing it will definitely involve slipping the clutch more on take off but lower the rpm at cruising speeds , again for your mum maybe not a bad thing!

There are many web pages which will calculate this for you and draw images of the changes for you, but at the end of the day it all comes down to feel.

One good thing, is that a higher side wall will protect the rims a little.

In my experience the ride in all A1's is go-kart like.
It will also make your speedo inaccurate I would have thought as the amount of wheel rotation would now equate to a different distance moved.
 

matthewobiah

New Member
I unfortunately went through massive pot hole and it destroyed my tyre and maybe even shocker? It was quite massive bang with front left wheel :(
So, I have purchased used 2x 245 35 R19 tyres, but I have 2x 235 35 R19 ones. And now, I mold removal Bloomfield michigan don't know which size should I put on the back and which in the front ??
 

jay_wax

New Member
Hi guys need some advice got an A3 8P Sline black edition quattro sportback (that's a mouthful lol) with 225/40/18, on standard suspension
I need to change all 4 tyres
can I go 225/45 all around?
Also planning to put spacers on would it all be ok thanks

Sent from my SM-N976B using Tapatalk
 

Potterswheel

Well-Known Member
Gold Supporter
welcome aboard :welcome!:
The dimensions for the 2 tyres are :-
1647773989125.png


Why would you want to do this?
have you got some cheap tyres? do you want to protect your wheels?
You need to consider:- handling changes, speedo errors, gearing ratios, clutch life, TPSM settings. the increase you are considering is outside the normally recommended 3% increase.

Have a look here : https://www.parkers.co.uk/what-is/tyre-sizes/
or here : https://www.tyresizecalculator.com/

Put your car in your signature then you wont have to say it every time you post :welcoming:
 
Last edited:

jaymond.jedrie

New Member
Quick question my wee mums A1 has 225/35/18 fitted to it but Speed Test needs the 2 front tyres replaced asap l am in the train of thought to change them to 225/40/18
Reasons being

The ride quality is intolerable with a 35 profile
The price of 225/35/18 are a rip off they are actually the same price as my S3's 235/35/19 and in some cases brand dependent even more expensive car has only covered 6700 miles in 3 years and the Conti's are ******** already dreadful tyres had them on my previous S3
You will either have to see if your friendly tyre dealer will have them back - 0r buy two more for the the other end.
 

Gazwould

Registered User
welcome aboard :welcome!:
The dimensions for the 2 tyres are :-
View attachment 251527

Why would you want to do this?
have you got some cheap tyres? do you want to protect your wheels?
You need to consider:- handling changes, speedo errors, gearing ratios, clutch life, TPSM settings. the increase you are considering is outside the normally recommended 3% increase.

Have a look here : https://www.parkers.co.uk/what-is/tyre-sizes/
or here : https://www.tyresizecalculator.com/

Put your car in your signature then you wont have to say it every time you post :welcoming:

Throw that lot in the bin , in the real world tyres don't conform to maths .
 
Top