Rolling Diamter of Standard Tyres

[Kitty's VR4]

Can anyone confirm what the standard rolling diameter of our car's tyres were when they left the factory, I've ordered New Yokohama 235/45/ZR17's ADVAN Sports V103, just wanting to double check on what effect they'll have on speedo accuracy

 

[steveP]

oi ill get around to hosting my CarCalculator tonite, that does this.. and many other useful car calculations.

in the mean time ill give u some specs:

factory tyre size: 225/50/16 = 63.14 cms
ur size: 235/45/17 = 64.33 cms

difference in size = 1.19 cms increase

@ 60 ur speedo will read - 61.13 km/h
@ 100 ur speedo will read - 101.88 km/h


EDIT: heres the link
http://www.importjap.com/downloads/

but yeah appears to be down atm, ill sort it out 2nite after work/gym.

 

[Kitty's VR4]

Steve,

Thanks

If the rolling diameter is increased doesn't that equate to faster actual speed, the way your post reads it appears the opposite way round.

But thanks for the actual info...... excellent

 

[steveP]

yes ur correct..

ie, @ 60 ur speedo will read - 61.13 km/h

ur speed will read 60 when really doing 61.13.

 

[Kitty's VR4]

Cool, Thanks so much... I can live with a 1.88% speedo error.....

 

[bradc]

235/45/17 is a common size a lot of us run. I actually found that my speedo was always slightly optimistic when I had the stock 16" tyres on. When I changed to 235/45/17 I found that my speedo became 100% accurate.

 

[Kitty's VR4]

Even Better thanks Brad

 

[bradc]

pm me your email addy if you have excel, I'll send you an excel spreadsheet I created.

 

[Kitty's VR4]

Thanks Brad

PM sent

 

[Guest]

Go to www.carbibles.com and go to the Wheels and Tyres section.

They have a few calculators, the one of most interest is on the second page. You can compare any two tyres by punching in the width, profile and rim size then go click click click. VERY useful even though it talks in MPH

 

[steveP]

pfft excel spread sheets and online calculators that kinda sorta do what u want lol. wait till u see my calculator i wrote a few years back, *in my best Habib voice from fat pizza* OMG u'll be impressed uleh!

 

[Kitty's VR4]

LOL, I'm in imformation overload heaven....

But anything that helps members answer this question is good

Guys your all awesome

 

[bradc]

Steve - mine is probably similar to what you did, in mine you enter in the size and it automatically calculates everything for you. I just programmed it in Excel You probably used Java or something?

(yes I know excel isn't programming, it is just a long formula, don't shoot me)

 

[Guest]

I found this really helpful.

[thread=1788]Stock Wheel Sizes and Offsets[/thread]

I think one of the mods should make it a Sticky Post

 

[bradc]

Done it, bloody good idea!

 

[SiliconAngel]

Brad stop making stickies all over the damn place, ya muppet!! >.<

Guys we're working on a solution for keeping all the useful info we've collected over the past couple of years in a simple, easy to use reference - it will solve the issue of stickies and old, lost info for everyone who's not so crash-hot with Friendly Mr Search Button

 

[Guest]

Brad stop making stickies all over the damn place, ya muppet!! >.<

Guys we're working on a solution for keeping all the useful info we've collected over the past couple of years in a simple, easy to use reference - it will solve the issue of stickies and old, lost info for everyone who's not so crash-hot with Friendly Mr Search Button

Sorry, that was probably a little my fault. I PM'ed you but never heard anything back so i went over your head

 

[SiliconAngel]

Sorry Brock, I should have gotten back to you. We've been discussing that (and a lot of similar info) in the mod forum for a while now - rest assured I wasn't just ignoring you

And you two, try to keep it clean, willya?

 

[Kitty's VR4]

Ouwwwwww, my first post deletion(s), I must have been a really bad kitty...............

 

[mookers]

Bad Kitty! Go to my room!