225 vs 235 tires

[09bluewrx]

I have an 09 WRX that came stock with 225 45 17 tires , I noticed that the newer WRX's come with 235 /45 /17 tires ...
my question is : can I mount these bigger tires on my car ? I think the slightly bigger tires will look better ...anybody done this ?
Does it effect the computer or anti -skid ?

[wrx1234]

Yes you can mount slightly wider tires but you would be better off adding sways if you want to improve traction. Slightly wider tires wont grip much more... not enough for you to notice unless you got stickier tires. As for looking better they will balloon out a tad but they wont look much different.

[09bluewrx]

I would be adding only for looks , the car handles like it's on rails already .

[DemonWRX]

the 235/45 will be 1.4% bigger....so when your speedo reads 100, you are actually going 101.4....so no real change to any of that. It might ever so slightly effect your alignment, so you might want to have that done for even wear....though if you are on stock alignment currently, that would be an improvement mod as well

[Anub1s]

I would be adding only for looks , the car handles like it's on rails already .

That makes absolutely no sense.

[A265]

I think 235's on a 7 inch wheel might be pushing it. Did you change your wheels or are you planning on buying new ones?

[Mf645]

Look at the specific brand and model tire. Should be no problem with a 235/45/17 or a 235/40/17. I went from 235/45/17 on the wifes car to a 245/40/17 and the car looked better and the tire was 2% shorter

[Annihilator817]

I'd defintely go with the 235/40/17 over the 235/45/17.

235/45/17's (and even 225/45/17) are really tall tires. They will REDUCE the amount of torque you are able to put to the ground. And on the WRX with it's rediculously long second gear, a little gearing reduction via the tires works wonders.

You can definitely fit 235/40/17's on a 7" wheel. You can even fit 245/40/17's on a 7" wheel without the tread deforming.

[09bluewrx]

That makes absolutely no sense.

I would like to fill out the wheel wells a little ...

[DemonWRX]

going from 225 to 235 makes the tread 10mm wider. With an aspect ratio of 45, that willmake your sidewalls about 3mm or so taller, which means you will likely not notice just looking at it.

If you want to fill outthe wheel wells, you would want to go to 18" wheels with 235/45R18 tires. This will, however throw your speedo off by 5.4%....meaning when your speedo reads 60mph you will really be going 63mph. This will be fine as long as you adjust your driving accordingly and realize you will be falsifying your odometer (which may or may not be a legal issue)

[Venom351R]

If you want to fill outthe wheel wells, you would want to go to 18" wheels with 235/45R18 tires. This will, however throw your speedo off by 5.4%....meaning when your speedo reads 60mph you will really be going 63mph. This will be fine as long as you adjust your driving accordingly and realize you will be falsifying your odometer (which may or may not be a legal issue)

Can that be adjusted with a Cobb AP? I was wanting to go up to 18's but was unsure what it would do MPH wise or actual mileage driven.

[DemonWRX]

No, it can not.

Subaru is one of the only car manufaturers with a cult enthusiast following that does not give you access to change this. I have been around and around with not only my local dealer, but 3 different SOA reps about this. No way to change it.

According to SOA, that is handeled by the BCM (body control module) which can not be accessed. There is a slight chance that you could swap your WRX BCM for an STI BCM to correct this, but I have no way of validating that....just a theory I have....as far as I know, no one has done that as of yet.

[mangostick]

I found that my 2010 read slightly high on the factory wheels/tires (a couple mph or so depending on speed) so when I switched to the '11 wheels and tires (factory set) It read dead on. Now, by gps its also dead on@ highway speeds. Again to reiterate.. this was a factory wheel/tire combo from 2010 and a factory wheel/tire combo from a 2011 fitted to my 2010 car.

FYI, there are no set standards for overall width on tires. One mfr 235 can be up to 245 wide and vice versa. If you're going to put a wider tire on the car, get wider wheels that properly match the new tire width. Its safer that way and maintains proper handling characteristics. Sure it might not distort the "tread" but a wide tire on a narrow wheel does really interesting things to the sidewall. Just like a narrow tire on a wide wheel is also a bad Idea. Even though its stupidly (as well as just plain stupid) popular right now.

[DiRty Impreza]

don't do 235/40/17, your car will ride a lot rougher. you'll feel it in the suspension more, and more likely to bend a rim. Specially if you live in Ohio you won't feel, or barley notice a difference from 225 to 235. If your going for looks buy a wider and taller rim, that will fill your wheel well, and allow you to put wider tires on without a problem. 18x8 is a good choice, 18x8.5 = perfection.

[Venom351R]

No, it can not.

Subaru is one of the only car manufaturers with a cult enthusiast following that does not give you access to change this. I have been around and around with not only my local dealer, but 3 different SOA reps about this. No way to change it.

According to SOA, that is handeled by the BCM (body control module) which can not be accessed. There is a slight chance that you could swap your WRX BCM for an STI BCM to correct this, but I have no way of validating that....just a theory I have....as far as I know, no one has done that as of yet.

I already have an STI, how does that change things?