i was lookin at a tire sizing program -- http://members.aol.com/agspeed/tiresize.htm -- and it said that the tire height is off when ya go from 215/45-17s to 225/40-18s .. but its a size thats offered on the RS1.0 ... and other tCs that have 18s as the aftermarket package from the factory .. says that the stock tire height is 24.61 inches .. and the 225/40-18 tire height is 25.08 inches .. which to me seems like a lot off .. i did the calculating for the 215/40-18s and the tire height is a more comparable 24.77 inches .. which to me helps ya have a more correct speedometer .. so when i get 18s im gonna go w/ the 215/40-18s .. even tho i may loose a half inch on width .. ill be more correct on my speedometer .. and i guess if no one cares .. oh well .. i also heard that if u put taller tires on the car you actually loose a little in torque ..

yeah I have seen quater mile times with the tC on 17 and then to 18 and the car lost almost 2 tenths of a sec. Its a whole inertia thing... but who cares your ride will look nice.

I went with 225/40-18's on my new wheels. I'm putting them on this weekend I'll let ya know how big of a difference it makes. Here's is the info about going from 215/45/17 to 225/40/18 from the site I got my wheel/tire package from http://www.whalentire.com/tiresize.cfm?tiresize=2254018&manu=&vehicle=10379&finish=&sorttype=1&onhandlimit=1&boltpattern=0&diameter=0&smallwidth=0&largewidth=0&npp=0&crn=0&alt=no

instead of 225/40/18 get 225/35/18 DURR its almost perfect with stock

moved

yeah I have seen quater mile times with the tC on 17 and then to 18 and the car lost almost 2 tenths of a sec. Its a whole inertia thing... but who cares your ride will look nice.

That's pretty hard to attribute just to the tire size.....sooo many other variables:
reaction time, launch rpm's, engine temp, driver skill, the list is endless.

Something like a full second, I could see that, but 2/10ths....hell, many people wouldn't even be able to run back to back with only 2/10ths difference on the same car, same setup.

instead of 225/40/18 get 225/35/18 DURR its almost perfect with stock

says that the tire height will be 24.2 inches compared to the stock height of 24.6 .. still a little low i think .. id say stick w/ the 215/40-18s .. you will only be a 10th off of the stock height .. and its not a big deal to be the same width ..

moved

i meant to put it in this section .. sorry

I understand what your saying but they had the same driver for each trial and they did more than 2 runs... It was done by some magazine and it showed a consistent range of about .2 slower than stock 17's.. just what I read... but it makes sense. I saw on speed channel when they upgraded this RSX's brakes to a big brake kit and even though the brakes were lighter they still lost horsepower. Its all physics bud...

I'd have to see the article, to truly believe it. But this post makes it sound a lot more believable than the first one you posted :)

But yes, if you just took a larger diameter rim, then yes, you could see slower times.

However, when smart people upgrade rim sizes, they typically use a rim that *weighs* less, as well as move to a lower profile tire. This way, you get a lighter weight rim, better looking tire that also weighs less (lower profile tire) and same overall height. There fore, inertia is not an issue.

Go with 225/40/18, I have NO problem with them, I even lowered my car with TRD springs. Many scions have lowered and put on 225/40/18 or even 215/35/19. Dont worry!

Just ordered 18's for my xb. They should be in by next week. I went with the 225/40/18 myself. My buddy works at a local Toyota dealer and he is ordering me the TRD springs. If anyone has any pictures of an xb dropped with TRD springs, that is sitting on 18's, I'd like to see it.

Just ordered 18's for my xb. They should be in by next week. I went with the 225/40/18 myself. My buddy works at a local Toyota dealer and he is ordering me the TRD springs. If anyone has any pictures of an xb dropped with TRD springs, that is sitting on 18's, I'd like to see it.

Go to Tread & Butter under Technical, that would give you instant pictures rather than wait here for replies! Or you can do a search! But they are all mainly in Tread and Butter!

I'm running 235/40r18s.
I think they ride great. a little rubbing on hard dips, but nothing bad. I'll take that over sacrificing the ride quality

I have TRD springs with 225/40/18 and i havew no rubbing and the ride is a lot smoother that with 17's. I love this tire size its perfect. I live in an area with a lot of bad roads so i can use the extra tire....any smaller and i could be risking my rims being bent.

wow 235 would look nice

I'm running 235/40r18s.


that tire size is dramatically bigger then stock .. yer goin from 24.6" to 25.4" .. yikes .. if ya go 235/35-18s .. its 24.47", only about 0.1" shorter ... much more reasonable .. little lower profile tire .. and ya get the width of the 235 .. and ya shouldnt have too much problems rubbing .. technically thats a plus 0 size from the 215/40-18s ..

GO WITH 44" SUPER SWAMPERS WITH SOME AR WHEELS. YEEEEEAAAAAHHHHHHHHAAAAAAAAA THEN ADD UP SOME DUAL EXHAUST WITH GLASSPACKS, AND A BULL BAR :rofl: :rofl: :rofl: :eyebrow: :eyebrow: :lalala: :lalala: :doh:

hahaha

HEy guys looks like im going with 18" 225/40 tires and trd springs... just wondering whats the offset on your rims? cause i don't want to have any rubbing issues with my TC....

Mine are 18x8 +40 offset
http://www.scionlife.com/gallery/data/500/221991_101_full.jpg

and the 235 series tires are perfect (for me).. I don't like sacraficing ride for looks (anymore)

Nuespeed introduced a forged 18x8 +35 in a 5x100 pattern this year.
I'd like to see how those fit.
http://www.namotorsports.net/detail.cfm/part_cd/NSRS101880355100BLK
cost start around 550/wheel

your 235s wont rub?