I have used the search bar and read the posts etc so plse dont shhot me but wanna b absolutely sure these will fit b 4 shelling out hundreds on sumfin that dont work!

mk1 vrs running stadard spiders so 17"et38 205/50 tyres goin to an 18" et35 runnin 225/40 profile tyres

Is that goin to work?

will also be using weitec springs so sitting maybe 20mm lower all round

Thanks in advance for my asking the question agen

Yes!

I'm assuming the wheels are 8"x18"?

If so, then you've got the tyre size correct at 225/40-18.

But I'm not sure on that offset. Obviously the wider you go on the rim the lower the offset needs to become. By my calculations you need an offset of 25mm with an 8" rim, to maintain the same rim edge to strut clearance that you have with the standard alloys. So with a 35mm offset the inner rim will be 10mm closer to the strut. Doesn't sound much, but worth checking first.

I'm sure someone will have tried this.

But 225/45/18 will give you an almost identical rolling circumference to your current tyres (you will be going 0.26mph faster at 70mph - whereas the 225/40/18's you would be going 2.14mph slower at 70mph, 235/40 and 245/40's will reduce this a bit, but you may then have clearance issues)

Look here for the comparisons

yeah they are 8by18" and that is the correct offset for that wheel size i believe so was reasonably sure they wud fit but just needed to be spot on about it.

cheers for the info on the calculator!!

I have 18x8s with 215/40/18s

But I'm getting 225/40/18s next time.

yes they will work. My previous alloys were 18"x 8j et33 offset. Even though they were pretty wide they didn't catch/rub even with the same Weitec springs that I've got fitted

yes they will work. My previous alloys were 18"x 8j et33 offset. Even though they were pretty wide they didn't catch/rub even with the same Weitec springs that I've got fitted

cheers oggy thats my mind well n truly made up then!!