Higher tyre wall ride improvement .

funksta · Post by **funksta** » Sat Mar 06, 2021 9:09 pm

I was thinking of putting higher walled tyres on the rears . From 255/35 18 to 255/45 18 on the rears . Just to improve the ride if possible . Has anyone tried this . Will it affect handling? . Will it fill the wheel arch more , or just raise the ride height ? . I'll be using the same make of tyre, front and rear.

rawpilot · Post by **rawpilot** » Sat Mar 06, 2021 9:35 pm

I was having similar thoughts.
But would the TPMS get confused if the rear tyres spun at a different speed to the front ?

This is a useful comparison site:

https://www.tacomaworld.com/tirecalc?ti ... 255-45r18

I presume the speedo comes from the rear wheel speed ?

Mr Tidy · Post by **Mr Tidy** » Sat Mar 06, 2021 9:38 pm

I suppose it will affect handling.

It'll definitely fill the arches more as well as raising the ride height, but it will also affect the accuracy of your speedo.

Put the details in here to see by how much:- https://www.willtheyfit.com/

funksta · Post by **funksta** » Sat Mar 06, 2021 10:01 pm

Thanks for your help . I think they will fit ok . As for speedo readings , judging by my sat nav , the car reading is generally about 3mph slower than the nav reading . The nav is usually correct when passing speed reading displays on approach . Just my in my mind but i think there must be more absorption in a higher wall .

brillomaster · Post by **brillomaster** » Sun Mar 07, 2021 1:10 am

Going from 35 to 45 profile is a big change, over 7%. I personally wouldnt change things up that much.

If i was looking for better ride comfort, id drop to 17s. And maybe go for 245 45 r17s.

Presume youve already ditched the run flats? Thatll make a big difference.

funksta · Post by **funksta** » Sun Mar 07, 2021 1:56 am

Yeah ditched the runflats . I'll look into a 40 tyre wall as well . Still contemplating because I need to change the rears. I dont really want to go to 17s. Cheers

mr wilks · Post by **mr wilks** » Sun Mar 07, 2021 8:11 am

funksta wrote: ↑Sun Mar 07, 2021 1:56 am Yeah ditched the runflats . I'll look into a 40 tyre wall as well . Still contemplating because I need to change the rears. I dont really want to go to 17s. Cheers

255 45 on a 8.5j rear is too much , 245 40 18 is the perfect rear tyre size on 8.5j factory rears , better comfort , reduces arch gap , more protection for the rim & should make the speedo more accurate . You could also fit a 215 45 18 to the front though generally the 225 40 is ok

rawpilot · Post by **rawpilot** » Sun Mar 07, 2021 9:56 am

Are all the factory 18" 108 wheels width 8.5J rear and 8J front ?

Big Andra · Post by **Big Andra** » Sun Mar 07, 2021 10:04 am

rawpilot wrote: ↑Sun Mar 07, 2021 9:56 am Are all the factory 18" 108 wheels width 8.5J rear and 8J front ?

Yes.

funksta · Post by **funksta** » Sun Mar 07, 2021 12:37 pm

Thanks for the reply Mr Wilks. Good info for me. I going with vredstien ultrac vorti, already have them on . They have great grip in the dry ok in the wet . https://youtu.be/4NcenJ0zmAY . Have a look at this test .

thetenksi · Post by **thetenksi** » Sat Apr 03, 2021 2:40 am

a bit late but here's mine after going up a size for the side wall, 255, 40, 18 rear and 225, 45, 18 front. I can't say i feel much difference in the ride quality but I much prefer the look of it now with less of an arch gap

https://imgur.com/gallery/sx1AawP

funksta · Post by **funksta** » Sat Apr 03, 2021 8:56 pm

Thanks for the reply . I had to stick to the 255 35 18s , as my wheel arch gap was too tight in the end . My springs have gradually lowered a bit since fitment 3 months ago . Your stance looks better on your zed now

HU51A_FU · Post by **HU51A_FU** » Fri Apr 09, 2021 3:24 pm

I run 8j front 215/45ZR18 on the front and 9j rear 235/40zr18. Comfort wise its lovely!

lmacmil · Post by **lmacmil** » Wed Apr 14, 2021 11:57 pm

mr wilks wrote: ↑Sun Mar 07, 2021 8:11 am 255 45 on a 8.5j rear is too much , 245 40 18 is the perfect rear tyre size on 8.5j factory rears , better comfort , reduces arch gap , more protection for the rim & should make the speedo more accurate . You could also fit a 215 45 18 to the front though generally the 225 40 is ok

I'm thinking of going this route on my 2006 3.0Si which will allow me to get a Grand Touring All-Season tire (Vredestein). I'm hoping that between the higher aspect ratio and the tire style (currently have summer tires) that the ride will improve somewhat. We shall see!

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