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Model specific boards => Golf mk4 => Topic started by: l4v15 on 27 February 2008, 23:11

Title: speedo with 18's
Post by: l4v15 on 27 February 2008, 23:11

hi. how far out will it put your speedo if you have 18's on the gti t? just wanted to know how far out mine will be. Also, when you lower the mk4 does it put the tracking, wheel alinement, camber etc out by much?

Title: Re: speedo with 18's
Post by: richw911 on 27 February 2008, 23:34

Quote from: l4v15 on 27 February 2008, 23:11

hi. how far out will it put your speedo if you have 18's on the gti t? just wanted to know how far out mine will be. Also, when you lower the mk4 does it put the tracking, wheel alinement, camber etc out by much?

You will have lower profile tyres on the 18's prob (225/40/18) so the amout you have gained on the rim you will lose on the prifile of the tyre.
The radius will be the same - So it will not put the speedo out  :wink:

As for camber etc that will depend on how low you go TBH. Always a good idea to get it all checked after lowering tho :afro:

Title: Re: speedo with 18's
Post by: Chris 'N' Jen on 28 February 2008, 08:43

18's with 225/40/18 tyres shows you go slower by about 1 mph i think.

heres a handy little converter
http://www.dakota-truck.net/TIRECALC/tirecalc.html

type your standard tyre in A and you intended tyre in B and say submit, then click on full analysis.

 :smiley:

Title: Re: speedo with 18's
Post by: topher on 28 February 2008, 09:11

tbh the inaccuracy of your speedo probably gives more deviation than the very slight change in rolling radius. Above 30mph mine was constantly 4 - 5 mph out according to gps.

Title: Re: speedo with 18's
Post by: l4v15 on 28 February 2008, 20:43

yea good stuff. thanks.