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Old 08-10-2005, 03:34 AM   #1
hilfiger4you
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Default Will 18in rims on STI affect alignment

Hey guys, just got a 05 sti. I am thinking about getting some 18inch rims. Just wondering if thats a bad idea in terms of affecting the alignment, I am not looking to mod the car, and the rims are for show. The car handles great so I would;nt do anything if it compromises the proformance.
thanks
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Old 08-10-2005, 04:29 AM   #2
ripvw
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Your STI comes with some very strong, very light 17x8 BBS rims and 225/45x17 Bridgestone RE070 tires. There are not very many tires that will perform as well as the RE070's in the dry, so you would need to be careful which 18" tires you choose to maintain performance. The Falken ST615, Yokohama Neova AD07 and the Hankook Ventus RS2 Z212 tires are all equal to or better than the RE070's in the dry and would offer a performance alternative in the 225/40x18 size. They are all at least a pound or two lighter than the 27lb RE070's so that won't hurt performance either.

The BBS wheels are great - but expensive to replace. An 18x8.5 alternative that I would recommend is the SSR GT2. At 17lbs they are almost as light as the BBS wheels and are a 1/2" wider to help increase the width of the contact patch and improve dry cornering. Of course, you may already have some other wheels in mind, but from a performance perspective the 18x8.5 size is a good option to consider to allow you to maintain performance when going with 18" wheels.

a real performance enhancement could come from rolling the fenders and going with 18x9" wheels and 265/35x18 tires. it would look way cool too...

changing wheels and tires does not usually affect alignment, but it does give you an opportunity to improve upon the factory alignment settings and get even better handling. The strut suspensions on the Imprezas tend to gain camber when cornering, causing the tires to roll inwards exactly when you don't want them to. To compensate, we add more static negative camber both front and rear - making the tires look like this: / \. Adding some front and rear camber bolts for $20 to $30 per pair will allow you to adjust the front camber to about -2 degress and the rear to -1.5. This will give you more front grip - reducing the built-in factory understeer - and allow the car to handle better when cornering. To prevent the extra camber from eating up your tires, make sure the alignment tech sets the toe to 0 degrees front and rear.

If you really want to improve the STI's handling, add larger front and rear swaybars - 22/22 minimium, 24/24 even better. This will help to control body roll and even more importantly help to maintain camber when cornering. I know that you don't want to mod the car, but tests have shown that the STI really benefits from the larger bars. compared to most other suspension mods they offer a real bang for the buck improvement in performance.

having said all this, if it was my STI I would go with 17x8.5 wheels and 255/40x17 tires - best performance combination for the STI in my mind. But for running on the street it really won't make that much difference, so get the 18's if you want them - just get good wheels and tires since you already have one helluva car
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Old 08-10-2005, 08:35 AM   #3
STiyiyi
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Default

Nice post. I have a question regarding the proposal of going the 18X9" route. If I did do that and roll the fenders, would there still be any projection of the wheel/tire beyond the fenderwells? If not, all I need to do is find a competent person to do the rolling. Are there many manufacturers that make a 18X9" wheel for the '05 STi?
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Old 08-10-2005, 02:45 PM   #4
hilfiger4you
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Wow thank you RIP. that was great info. I was thinking 18x8 wheels. So if I get 18x8 wheels and 225 tires. would the alignment be off some what to wear the tires ? I mean do I have to get at least alignment check?
thanks
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Old 08-10-2005, 05:55 PM   #5
bsbg
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Quote:
Originally Posted by hilfiger4you
Wow thank you RIP. that was great info. I was thinking 18x8 wheels. So if I get 18x8 wheels and 225 tires. would the alignment be off some what to wear the tires ? I mean do I have to get at least alignment check?
thanks
Changing tires will not affect your alignment.

That said, you should have it checked and set because most factory set ups are not perfect.
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Old 08-10-2005, 06:51 PM   #6
eqlized_aero
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Old 08-10-2005, 08:33 PM   #7
dchou
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On the 05 STi you cannot roll the rear fender, there is nothing to roll. Unlike the 04's. The 05 STi has more room in back stock. You should search to see if anyone has put a 18x9 wheel successfully.
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Old 08-10-2005, 09:11 PM   #8
kcook
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dude.. u have 17x8... thats plenty dude... it sux enough the 05 wrx's come with 16x6.5.. and 04 sti with 17x7.5... , but hey
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Old 08-11-2005, 01:33 AM   #9
ripvw
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Quote:
Originally Posted by dchou
On the 05 STi you cannot roll the rear fender, there is nothing to roll.
umm - never heard that before...

Quote:
Originally Posted by dchou
The 05 STi has more room in back stock.
now that I've heard - but I still think that any 9" wheel will be tight

Quote:
Originally Posted by dchou
You should search to see if anyone has put a 18x9 wheel successfully.
ok:

http://forums.nasioc.com/forums/show...highlight=18x9

http://forums.nasioc.com/forums/show...highlight=18x9

http://forums.nasioc.com/forums/show...highlight=18x9

looks like at least 1 running 18x9, a couple of others who are thinking about it and someone else running 19x9!!!
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