Changing From 17s To 18s

[marko72]

Seasons greetings.

Santa will be delivering a nice set of 18s this xmas, but I have a few, perhaps basic questions, so hope you folks can help. Currently have my02 wrx with standard 17s and tyres on. Car lowered on Eibach springs.

Hope this doesnt sound too daft but I have read on the interweb that going to 18s can cause a few issues, such as my speedo reading incorrectly?? Also my car tramlining?? what does that actually mean?? Also having had the car lowered I dont want to ' raise the height' with the bigger wheels as such.

I am confident that the set ive chosen, which are popular with scoobs will be ok but just want to check this out.

Thanks and ho ho ho

Mark

Edited December 23, 2009 by marko72

[Phil MC]

Your speedo should be fine so long as you have the correct profile of tyre fitted (Same wheel/tyre diameter as the 17s).

If the tyres are wider than previously I'd maybe consider checking your geometry out to prevent uneven tyre wear and ensure the maximum amount of grip to the road?

I'm no tyre expert, so this is just my opinion.

Hopefully someone more knowledgeable will come along and confirm things 100% for you .

:star:

Edited December 23, 2009 by Phil MC

[C_WRX]

I have an 04 WRX with prodrive springs and 18's.

When I had the springs fitted I got the wheels at the same time. I also had Dunc at Hypertech check the geometry, which was just as well as it was out.

If you've had that done don't think you'll have any issue. If not consider it.

I also have a front splitter on so my car so can no longer visit multi-storey shopping car parks - it's just another plus !!

As said, sure the experts will be along some time soon. This is just my experience of it.

[marko72]

I had the geometry done when getting the springs/ALK fitted by Dunc and all was good. Pretty sure the 18s are wider than my current 17s.

My current tyres are I think 205/45/17 so was assuming I would go for 215/40/18 with the new wheels. The website I was on seemed to suggest 215/35/18 would give the correct readings.

Any thoughts?

Thanks Mark, and cheers for the replys so far.

[Spaceman]

you should be on 215/45/17 with the standard wheels and either 225/40/18 on the 18`s or you could run 225/45/18

but stick with 225/40/18

[iainc]

  marko72 said:

Hope this doesnt sound too daft but I have read on the interweb that going to 18s can cause a few issues, such as my speedo reading incorrectly?? Also my car tramlining?? what does that actually mean?? Also having had the car lowered I dont want to ' raise the height' with the bigger wheels as such.

I've still got the std suspension on mine, but went from 17's to 19's (was originally going to go for 18's but got a good deal on the 19s ) In terms of tramlining, the car was MILES worse on the 225/45/17 RE070s than it was on either the Toyo of Eagle F1s I've on now (235/35/19). I'd say if anything the bigger wheels felt more comfortable than the smaller ones... although potholes become things to avoid at all costs even more as the lower sidewalls mean it's miles easier to get a puncture if you crash thru' one.

[marko72]

  Spaceman said:

you should be on 215/45/17 with the standard wheels and either 225/40/18 on the 18`s or you could run 225/45/18

but stick with 225/40/18

Cheers spaceman, yes they are 215/45/17. 225/40/18 for me then.

thanks.

[marko72]

  IainC said:

I've still got the std suspension on mine, but went from 17's to 19's (was originally going to go for 18's but got a good deal on the 19s ) In terms of tramlining, the car was MILES worse on the 225/45/17 RE070s than it was on either the Toyo of Eagle F1s I've on now (235/35/19). I'd say if anything the bigger wheels felt more comfortable than the smaller ones... although potholes become things to avoid at all costs even more as the lower sidewalls mean it's miles easier to get a puncture if you crash thru' one.

cheers, sounds good. Hate potholes, worst one I ever hit broke my front wheel, instant deflation and came to a halt on the wrong side of the road. Once the car was of the road, I took pictures of the offending hole and noticed the pile of different style broken wheel trims lying around, took pics of them , pics off to the local council with letter. Hey presto, hole filled in one week later and cheque in post to cover my losses. Power to the people

[iainc]

  marko72 said:

cheers, sounds good. Hate potholes, worst one I ever hit broke my front wheel, instant deflation and came to a halt on the wrong side of the road. Once the car was of the road, I took pictures of the offending hole and noticed the pile of different style broken wheel trims lying around, took pics of them , pics off to the local council with letter. Hey presto, hole filled in one week later and cheque in post to cover my losses. Power to the people

Yeah, I hit a pothole with the 19s and although it wasn't as severe as yours, it started a slow puncture. Was stopping in less than a mile anyway. When I had the tyre changed I checked out the rip in the tyre and it was a fairly long cut, so looked like the rim of the wheel had chopped thru' the sidewall as it had hit the pothole. Would have been bad enough if the tyre had been old, but it was about 3 months old at most... worse still in the period between buying the original set, the price per tyre had gone up about £15-20