Some useless Information!!!!!!

[Richard]

Hi.All I have a Bravo HGT to which I have fitted 17" Rims with 215x45 Tyres. I was curious to find out how much the tyres would affect my Speedo Readings. Fitted with the standard tyres, 195x55x15", the speedo would read 'fast' by approx 10%, ie at an indicated 80mph -- true speed 72(approx). With oversized tyres the speedo would read 'slow' by approx 10%. So using a GPS (Sat Nav) I carried out a series of speed runs. (I normally use the GPS on my Boat where I find that it is pretty accurate), anyway this is what I found :-
Speed MPH(on Speedo) / Speed MPH(on GPS)
40 39.8
60 59.7
80 79.5
100 98.8
So although my Test was not very 'Scientific' it would appear that my larger tyres have almost cancelled the normal 10% Speedo error!!!
Cheers,
Richard

 

[Steve D]

Do your 215's rub?

If they don't then I may consider going for the 215/35/18's next!! instead of the 205/40/17's.

 

[Sid]

Untitled

It'll have more to do with the width of the wheel - 195s & 205s were standard (If I remember right) - that means you can expect a half inch on each side to cater for snow chains. However if you were to slap on 8x18s then the tyes rim guard at least would probably foul the arch.

Places like Xtreme and Elite will roll your arches - its fairly painless unless your car has hidden filler!!

Sid