Docile 64 Report post Posted November 22, 2006 hey guys anyone know the mathematics of changing the mags and tire sizes so that it would still have the same circumference?? or better yet a site that does it for you? we bought new shoes for the 7 series and 60 km = 70 on the speedo ( tested on the road side speed laser thingi) mags and wheels before were 16' basketweeve bbs on 235 60 series.. its on 18' 255 all round, 35 series now.. i compared the tyres side by side and the new tyres are a bit shorter.. dumb ass tyre fitters didnt put in the right tyres in !! Quote Share this post Link to post Share on other sites
E30-323ti 66 Report post Posted November 22, 2006 hey guys anyone know the mathematics of changing the mags and tire sizes so that it would still have the same circumference?? or better yet a site that does it for you? we bought new shoes for the 7 series and 60 km = 70 on the speedo ( tested on the road side speed laser thingi) mags and wheels before were 16' basketweeve bbs on 235 60 series.. its on 18' 255 all round, 35 series now.. i compared the tyres side by side and the new tyres are a bit shorter.. dumb ass tyre fitters didnt put in the right tyres in !! LOL 255/35's are tiny on a 7'er Try 255/45 or 275/40 on 18's or 235/50's if you have skinny rims (8") http://www.miata.net/garage/tirecalc.html Quote Share this post Link to post Share on other sites
Docile 64 Report post Posted November 22, 2006 (edited) well we presumed that they knew what they where doing.. after all they were a tyre shop and should know what they where doing.. gonna contact em today and see if they can replace it.. Edited November 22, 2006 by Docile Quote Share this post Link to post Share on other sites
martyyn 2 Report post Posted November 23, 2006 Hahaha never trust a tyre shop to get it right.....of course they should, but always check your numbers first. I currently have 235/50/18 on the front with 255/45/18 on the rear with staggered m-pars, which is BMW standard for 18's on a 7 If you want larger you can have what I used to have (but was a little harsh on NZ roads) which was 255/45/18 on the front and 275/40/18 on the rear. No way should you have 35's on there. You should have a sticker on the car by the drivers door that tells you the correct sizes. Quote Share this post Link to post Share on other sites
martyyn 2 Report post Posted November 23, 2006 Your 7 was probably not designed for 18 inch wheeels, probably handles worse than if you went for a better combination closer to the original tyre sizeAs someone who has driven lots of 7's with 15', 16', 17' and 18' wheels, this has to be one of the funniest things Ive ever heard.What I hope you meant when you said 'not designed for 18 inch wheels' was that it wasnt right to have 35 profiles. Quote Share this post Link to post Share on other sites
Docile 64 Report post Posted November 23, 2006 (edited) so your saying a 7 series wasnt ment to have 18'? thats bull.. if your saying that 18' with 35 profile tyres are bad for the car,yeh it is.. but the ride is pretty much the same.. just a bit lower the car handles quite well now with the bigger tyres.. but its just the speedo atm that was affected by the small profile tyres.. and the rear can still handle a wider set of mags. our 18's are 8.5' wide. the speedo was working fine before the change.. and yes 60 was around 65ish on the speedo.. my bad. Edited November 23, 2006 by Docile Quote Share this post Link to post Share on other sites
Docile 64 Report post Posted November 23, 2006 we've had it aligned and all at shock shop which took them a good 2 and 1/2 hours and all was done.. report was that at the current 16' setup, driving it would lead to tire wear and crap.. they adjusted it to accomodate the new 18' set up.. which i s now all good. they checked all the suspension components as well and was all sweet.. although they told us to go to a $tealer to sort out the ASC calibration or sumthing.. and the steering wheel adjustments done.. all at the cost of 80 bucks Quote Share this post Link to post Share on other sites
Docile 64 Report post Posted November 23, 2006 (edited) Sounds good, What do you mean by steering wheel adjustment? and 80 bucks for 2 and a half hours works out at $32 an hour which is a bit cheap. Did they suggest any suspnesion upgrades to go with the alignment? not that there are a lot of option fopr 7's and you have not mentioned what series the car is the steering wheel angle or sumthing had to be re setted and checked or sumthing like that which required a special tool (which should be done every time wheel alignments are changed, so im told).. cant scan the report coz its in the 7 series and its not here.. yeh i was kinda suprised that IT TOOK THEM 2 HOURZ to finishe the whole thing was thinking about 1 hour or so would do.. that guy is KEWL !! i would recommend him to do your alignments in west auck.. our tyre guy ( not the guy where we bought our new tyres from) recommended that place to have it done, hence we went there and A + service... kinda boring though waiting for 2 hourz... should have taken 2 cars but all worth it they where hecka better from where i got mine done.. (took mine for a joy ride) i didnt even get a report sheet .. crap scum bags.. although it was only 50 bucks.. and nah, he said that the suspension was still in mint condition, even the shocks were in mint condition. Edited November 23, 2006 by Docile Quote Share this post Link to post Share on other sites
