Hey. Basically my Ford Fiesta 2013 came with 15 inch Steel wheels and I just bought 17 inch alloys to replace them with. However I don't know what size of tyres I will need to meet the same diameter or how changing them will affect my car. Yes I am an idiotic impulse buyer but could anyone help me out?

I have an image of my current wheel size on my 15 inch wheels.

Depends what width the new alloys you've bought are.

The Mk7 Fiesta normally runs 17" wheels on 205/40/R17, but that's with the OEM 17 x 7 wheels.

Ideally you'll need to get the car re-programmed so it can adjust the speedo, ABS, etc for the new rolling circumference. You can use online tools to see how far out it will be otherwise.

Also don't forget to tell your insurance company.

The alloys are OEM I didn't want aftermarket Alloys. 

So how would I go about calculating what size tyres I need based on the size of my alloys? 

 

sorry if this is all very annoying but I want to learn and appreciate your help.

As they are OEM, then I'd stick with 205/40/R17 tyres.

Thank you!

Just remember if you don't get the car re-programmed your speedo will be 3.47% out. (http://www.tyresave.co.uk/tyre-size-calculator/)

Who would you suggest to re-program it?

Any Ford dealer can do it, make sure they don't try and quote you more than half an hours rate though.

It might be possible for a local garage to do it, just depends if they have the right equipment.

if I go to my Local Evans Halshaw or Arnold Clark will they fit the tyres onto the alloys for me and fit them aswell as re-program it?

Yeah should do, they might want a kidney for it though, lol.

Just get a fixed price from them first and query if it's any more than 1-2hrs work.

Forgive me if this is taboo but could halford do it as they sell the tyres and fit alloys aswell as wheel alignment and all that jazz?

You'd have to ask them if they have the equipment to re-calibrate the tyre size for the speedo to be correct. It's the same as a local garage in that respect.

Halfords?   You said a naughty word.

Forgive me! 😂

On 10/08/2017 at 4:28 PM, Zektic said:

The alloys are OEM I didn't want aftermarket Alloys. 

So how would I go about calculating what size tyres I need based on the size of my alloys? 

 

sorry if this is all very annoying but I want to learn and appreciate your help.

205/40s are correct, will give the right overall circumference. These were available as a factory upgrade, interestingly the aftermarket upgrade makes note of steering rack limiter, nothing of any re-calibration though.

@Wiggy!

Steering rack limiter what does that mean?

 

Nice fiesta btw 😉

26 minutes ago, Zektic said:

@Wiggy!

Steering rack limiter what does that mean?

 

Nice fiesta btw 😉

Correct, steering rack limiter should be fitted with 17's. 

Essentially means your full lock isn't quite as far round as with smaller wheels. 

It's intended to prevent the inside of the tyre running on the arch liner.

They were about £15 as far as I can remember, should be a 5 minute job to fit, just a case of pulling back rubber boot and clipping them on.

Most people don't bother. I have upgraded to 17s and haven't used limiters, no problems with clearancr. I think they are for when you have heavy loads so the car sits lower, therefore closer to the wheel where it can rub.