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Anyone running 18 inch wheels
Posted: Wed Sep 14, 2011 2:07 pm
by rustyp
Anyone running18 inch wheels as I am consideringbuyingsome - does it raise the gearing much? Does it affect the ride quality?
Any opinions - cheers Russ
Re: Anyone running 18 inch wheels
Posted: Wed Sep 14, 2011 3:22 pm
by borntobag
Hi Russ
I am running a set of 18” BBS wheels and have been for about 2 years now.
I have shod them with 235/55/18 tyres as the 235/45’s that where on them gave a really harsh ride.
I find the extra height in the tyre wall gives a much softer ride, however they aren’t cheap new, so I made a set up from Ebay and a local part worn dealer, they worked out at about £40 each plus a fiver each to fit and balance them.
Also I had to trim about 3/4 of an inch off the inside edge of the front bumper to accommodate them on full lock.
Ratio wise, the speedo is more or less spot on now 70 indicated and 68 on the GPS, it was 8 mph out before.
There are plenty of tyre calculator sites on the net if you want to Google them to find out diameters and rolling circumferences etc.. and a lot say don’t go over a 5% increase, I think mine worked out at about 11%..oops , with no adverse effects, even the braking is fine.
Just make sure all the tyres are the same size if running an AWD and that includes the spare. Make sure you are aware of the bore diameter of the wheels as spigots may be required to take up the difference, if not they will wobble like a hell and can be dangerous and cause damage.
I have no regrets fitting them, I prefer the ride and yes it might be a bit slower of the mark but it cruses at a slightly lower rpm which might help with consumption if i hadn’t fitted a K&N filter and a stainless zorst.
At the end of the day 114.3 x 5 x 18 wheels are easy to get hold of and sell on, give it a go if you don’t like them put the originals back on.
Re: Anyone running 18 inch wheels
Posted: Wed Sep 14, 2011 5:10 pm
by rustyp
Thanks for the advice particularly for the sizes and the ride quality.
My speedo is virtually spot on checked with a GPS app on my phone (I'm running a 626 MPH speedo) so may well under-read
If I can get them cheap enough I may go for them - cheers, Russ
Re: Anyone running 18 inch wheels
Posted: Sun Jan 01, 2012 12:44 pm
by A1tony
I am looking at getting rid of my 225/45/18's as they are too hard And only 95 load index. 235/55/18 might be just the trick. The front end on mine is slightly lower than stock so should I worry..? Shaving a bit off the bumper doesn't worry me as the extra ride height might help over speed bumps that are a pain. My speedo is also out by about 9% high reading so should bring it back into line and also improve cruising economy.
Any views other than ones posted here ?
Cheers
Tony
Re: Anyone running 18 inch wheels
Posted: Sun Jan 01, 2012 12:51 pm
by francophile1947
rustyp wrote:Anyone running18 inch wheels as I am consideringbuyingsome - does it raise the gearing much? Does it affect the ride quality?
Any opinions - cheers Russ
The wheel size only affects the gearing if you fit the wrong size tyres - you can use this site
http://www.tyresave.co.uk/tyresize.html to check the sizes required.
I have 17 inch wheels and the tyres are much easier to find at reasonable prices

Plus you can fit higher profile tyres for comfort
