Speed differences on bigger wheels

[clone]

obviously bigger wheels and tyres give you a longer track with 1 rotation compared to little rims and tyres.

have people noticed any slight difference with 18inch wheels?

im prepared to put on 215 35 18s instead of the 215 45 18s that are on the wheels atm.

any ideas?

 

[ONPSI]

Put in standard wheel size then what you want and it will tell you how far out it will be either side from stock.

http://www.1010tires.com/tiresizecalculator.asp

 

[4piknup]

Is roughly 10% smaller wheel, so will make the speedo out by similar

 

[evo-gsr]

+1 ^

 

[EVO-00X]

Manufacturer Overall Outside Diameter measurements as per tyre placards on Lancer Evolution
195/65/15 = 634.5mm
205/60/15 = 627mm
205/55/15 = 605.5mm

Therefore the wheel and tyre combinations allowable under VSB14 would include, but not be limited to, the following which fall within manufacturer overall diameter specifications +/- 15mm (to be within 8% speedometer accuracy):
205/45/16 = 591mm
205/50/16 = 611mm
215/50/16 = 621mm
205/40/17 = 596mm
215/40/17 = 604mm
205/45/17 = 616mm
215/45/17 = 625mm
205/40/18 = 621mm
215/40/18 = 629mm
215/35/18 = 608mm
215/30/19 = 611mm
215/35/19 = 633mm

 

[clone]

cheers guys big thanks . been ratting my brain abit. and that link is saved forever

 

[4piknup]

But would a recalibrated speedo get you around the the vsb thing?
Because you could run a auto speedo drive gear and a set of say 245/35-18 (not calculated) and the speedo and odo would be correct

 

[EVO-00X]

Man, whatever the speedo needle says on our cars is incorrect anyway and they can be way off the true speed.
The VSB info above is just one way of proving to the authorities in black and white that you have maintained +/- 15mm overall diameter and at least some degree of speedo accuracy allowable under the rules.
You can use whatever rolling combination and speedo drive you want, but they only allow +/- 15mm overall diameter change over the largest and smallest combo available for that car from factory.
It gives you a lot of room to play with. You dont need to prove speedo accuracy as long as your new combo is within those specs.
Personally you'd want to get your speedo as accurate as possible so you dont fuk up on the road and get booked lol

 

[7zark7]

Thank you from me as well.
I'm going from a 205 50 R16 to a 215 45 R17 so it looks like the car will perform better on a long track but a short track will need lower a profile tire to aid acceleration.

 

[4piknup]

Thank you from me as well.
I'm going from a 205 50 R16 to a 215 45 R17 so it looks like the car will perform better on a long track but a short track will need lower a profile tire to aid acceleration.

That is a 2% change. Not enough to notice any difference IMO.

 

[clone]

Okay question again running my te 37s 5 stud with 205 40 17's. I obviously have to change my spare now. Was going to use FTO spare wheel with a 195/50R16 tyre which has a speed difference of 0.93% will this effect the car at all obviously now having different rolling diameters but 1%? will i do anything at all as ive seen some bound up diffs from idiots on commys using 20 inch and a 16 inch spare with a difference of 7%

 

[4piknup]

Okay question again running my te 37s 5 stud with 205 40 17's. I obviously have to change my spare now. Was going to use FTO spare wheel with a 195/50R16 tyre which has a speed difference of 0.93% will this effect the car at all obviously now having different rolling diameters but 1%? will i do anything at all as ive seen some bound up diffs from idiots on commys using 20 inch and a 16 inch spare with a difference of 7%

close enough boss. you could over or under inflate spare by 5 psi, if you want closer.

 

[cheeks]

Should pin that chart..

 

[Hypo]

Get a EVO VI spare

 

[clone]

you recon? are they a space saver one or normal wheel?

 

[EVOCPE]

Space saver, i dont think you can fit a normal size wheel in the wheel well

 

[Hypo]

That is what I have. It only goes on the back though with brembos. So if you get a front flat you need to move the wheels around. You could also try a s14 spare as well.

 

[clone]

lol evo 6 spare.. easier said then done i recon. In townsville i have trouble finding anything

 

[khubner1]

what i'd so is find a nice narrow alloy something similar to the steelie found stock on the coupe 195 wide and get a tyre to match 195 wide fitt nice and snug. std gsr alloy fit but sits alil high up as i've just found out my. spare is a std gsr alloy wheel and the cover plate sit about 5cm off the deck