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Author Topic: Increase tyre height from 225/40/18 to 225/45/18  (Read 7530 times)

Offline Lucky ducky

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Increase tyre height from 225/40/18 to 225/45/18
« on: March 06, 2019, 12:00:49 pm »
Hi have 2005 gti only used at the weekends and find it a little harsh on the the roads so was wondering if anyone had any views on going from a 40 to a 45 tyre there due for a change soon thanks

Offline pudding

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Re: Increase tyre height from 225/40/18 to 225/45/18
« Reply #1 on: March 07, 2019, 02:03:17 pm »
It will look silly and the overall gearing will be taller.

You'd be better off dropping to 17" wheels, or even 16s.  A couple winters ago, I ran 16" steels with winter tyres and the ride quality was phenomenal compared to the 18s!


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Offline Lewo

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Re: Increase tyre height from 225/40/18 to 225/45/18
« Reply #2 on: March 07, 2019, 10:08:24 pm »
Did you use a 50 profile on the 16s pudding?

Offline pudding

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Re: Increase tyre height from 225/40/18 to 225/45/18
« Reply #3 on: March 08, 2019, 09:09:33 am »
I think they were 205/55/16 from memory.   I did look into running 16" steels permanently as they're also lighter than the 18" alloys believe it or not, but 225/50/16 tyres are silly money, being an uncommon size.


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Offline Lucky ducky

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Re: Increase tyre height from 225/40/18 to 225/45/18
« Reply #4 on: March 08, 2019, 12:47:05 pm »
Thanks guys had forgotten about the gearing been higher have now reduced the tyre pressure to 30psi down from 36psi makes a huge difference

Offline pudding

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Re: Increase tyre height from 225/40/18 to 225/45/18
« Reply #5 on: March 08, 2019, 03:02:00 pm »
I always thought 36psi is pretty high but I guess VW found that pressure the best mpg vs handling compromise on the factory fitted tyres, what ever they were in 2007!

Some tyres are just too harsh with that pressure though, so what ever works for you.  I would say 30 is a tad low.  Try 32-33 all round, otherwise you might get under inflation wear.


2007 ED30 | 2009 TDI 140 | 2016 BMW 330D

Offline rich83

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Re: Increase tyre height from 225/40/18 to 225/45/18
« Reply #6 on: March 08, 2019, 08:01:23 pm »
What tyres do you have fitted?

Offline Lucky ducky

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Re: Increase tyre height from 225/40/18 to 225/45/18
« Reply #7 on: March 08, 2019, 09:42:24 pm »
Hi rich
Tyre's on it are Continental SportContactâ„¢ 5 these were on it when i purchased the car before Xmas. There's still a lot of thread all round but there over 7 years old

Offline pudding

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Re: Increase tyre height from 225/40/18 to 225/45/18
« Reply #8 on: March 12, 2019, 10:37:23 am »
ContiSports are normally pretty comfy, so it's probably their age.


2007 ED30 | 2009 TDI 140 | 2016 BMW 330D