[sniff]

Hello everyone,

I am new to the forum and looking for some insight on plus sizing. I want to upgrade the wheels and tires on my 03 G35 sedan 6MT to 18x7.5s instead of the OE 17x7s. The Tire rack recommends 225/45/18 rubber and Discount tire Direct recommends 245/45/18. Why the difference?? They both keep the overall diameter constant, but one gives more ground contact. Which one won't screw up the VDC system?

Any input is much appreciated!

Sniff

 

[struan87]

225/45/18 and 245/45/18 won't give you the same diameter. The first would be 652.5 mm and the second would be 670.5 mm (I think). I'm not sure how much that would confuse the computer. I'm looking at the same kind of upgrade, and I'm also curious about how that would work, since I can't find another tire size that's equal to 215/55/17. Has anyone else done this?

2003 Sedan 6MT | Sport/Aero/Premium | Desert Platinum/Willow | Fuzzy dice | Pictures

 

[lead_foot]

Here you go guys:

http://www.6mt.net/forum/topic.asp?TOPIC_ID=1017&SearchTerms=shoes

This is a handy tool to use for tire sizing:
http://www.miata.net/garage/tirecalc.html

The ones I got, as well as the 245/45/17's are a good match for the 17's.

As far as 18's go, the best match looks like 245/45/18's which gives you a lot of choices.

<font size="1">'03 AT Sedan | Brilliant Silver | Willow Leather | Sport | Premium | Aerokit w/Spoiler | Nav</font id="size1">

 

[sniff]

Thanks Lead for the sizing link I can see how 255/45/17 fit on your ride. However the best fit for the 18 are 235/45/18 but I'm limited in the choice of tires. The 245/45/18 make my speedometer slower, and the 225/45/18 make it faster.
As for the 255 on your car does it affect the VDC??