: Does changing rim size require programming?



zzzasy
03-23-07, 09:04 AM
Hi all, spring is coming or here and its time to replace the factory rims. It came with 17s and going to replace with 18s or if I can find a nice set of 19s I may go with them. Is there a consensus that the 20s are a little too much? Now, the real question, if I went from the 17s to 18s would the computer need to be recalibred? or 19s. If the computer does need to be recaled, who, where, etc.

thank you,

zzzasy
'05 STS

997tt
03-23-07, 04:24 PM
20's is big, but not too much. That's what i went with.

You don't have to recalibrate anything unless you mind your spedometre being a couple mph off at high speeds. When my spedo says im driving 57-58mph, im actually already at 60mph. No big deal for me... get's worse if you go to 100mph, and you barely feel any difference around town.

Of course, make sure diametres look the same. Pm me once your ready to buy and i'll refer you too someone that knows what hes talking about.

i'll have pics of my car on 20's in a week if you want to wait and see how it turns out :)

997tt
03-23-07, 04:39 PM
heres a great tool.

http://www.miata.net/garage/tirecalcold.html

scroll down. Put down the size your running now and the size your planning to run. Same ammount of revs means your spedo should be displaying the exact same way it was prior to the wheel swap.

zzzasy
03-30-07, 02:50 PM
thanks for the info. I saw your ride. Awesome!!!!!!!!!!!!

zzzasy
'05 STS

997tt
03-30-07, 03:28 PM
thanks for the info. I saw your ride. Awesome!!!!!!!!!!!!

zzzasy
'05 STS

np

post pics when the new wheels are in.. members here don't share enough :thepan:

thx for the comment too :thumbsup:

caddycruiser
03-30-07, 03:37 PM
It's all about getting the proper tire size in conjunction so your overall wheel/tire diameter is as close to the stock setup as possible--hence, why sidewalls are usually thinner as the wheel size increases.