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Questions on changing wheel size

14K views 13 replies 9 participants last post by  dnguyen5739  
Hi, I have a base model with 16" wheels. I'm installing a lift because I keep scraping stuff, and I'll definitely have room for larger wheels.

I know that others impreza trims come with 17" wheels, but if I put 17" wheels my speedometer won't be accurate. Also, since the whole thing is computerized, won't it get confused as far as RPM and gears? Plus, it won't report accurate mileage.

Is there an understanding available for dealing with these issues? Or is that simply unavoidable downside when having larger wheels?
The size of the wheel won't matter as long as you get a tire with a smaller sidewall to compensate and keep the height of the tire the same. Personally, and what a lot of people end up doing after they lift their car is switch to a 15 or 16 in wheel so that they are able to get a tire with a larger sidewall. The stock tires are about 25 in tall, so if you want to gain a lift by switching tires I would suggest going to a tire that is 27 in tall maximum. I have 215 65 r16s on mine and they give me an extra inch of ground clearance over stock. Add that on top of whatever lift you plan on installing and you should have all the ground clearance you need for around town and some mild off-roading. You have an advantage by already having 16s, as long as you like them that is.
As far as the gearing goes I've had no issues with drivability and shift points, but my car is noticeably slower especially off of the line since taller tires are effectively gearing you up. Nothing you can do about the mileage unfortunately. It's just something you have to accept as a side effect. Your speedometer will read slow as well. 40 mph for me is about 42, and 64 mph is about 70. The difference becomes greater the faster you go. Can I ask which lift kit you plan on going with? I know a lot of people go with the ADF kit, but if you want maximum safe height I suggest the 2/2.5in kit from Subieliftoz. it's about the same price as other quality kits and the strut tower spacers in the front have the top holes staggered from the bottom to help keep your alignment in check. The wait time is a little long, about 6 weeks for me but shipping was free from Australia and Matt throws in an adorable koala bear with your order. Totally worth it just for this 😁
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More pics please

I’ve been debating what wheels to get and these are at the top of my list. That’s the color of my car.
Thanks!
Bottom two pictures are before the lift. Just thought the comparison would be interesting. Was almost tucking tire in the rear. First time I took it off road with the new wheels and tires I was still belly scraping down most of the trails. Couldn't imagine not having a lift now.
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Here is my old Crosstrek with its street tires, 235/55/18, the mudders I had for the weekends, 215/75/15s and the new one with 235/60/17s. And a pic of what they look like next to the stock 225/60/17s it came with.


This will show you what folks are talking about when it comes to rim size and sidewall height.

Me? After three years of using the 15s, I'll never use them again. They caught all sorts of rocks in between the caliper and the wheel and caused screeching that would wake the dead. All four wheels had several gouges inside. Pic below to show what I mean.

(pics loaded backwards, but you can figure it out. :) )
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Funny you mention the gouges, happened to my 16x7 Sparco Terras. Killed two of em in less than a month.
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The lift is not what affects the speedometer, it's the larger diameter of the tires. Height wise the stock tires are 25 in tall versus the ones that I have which are 215 65-16s equal about 27 inches tall. You end up gaining about an inch ride height just with the tires.
As far as the lift goes there are many options available since our cars have been out for a few years now.
I ended up going with the Subieliftoz kit which gives a 2-in lift in the front and two and a half inch in the back. It's the only kit that I found that gives a higher lift in the back. The advantage of that is to counteract the Subaru saggy butt and keep the lift level.
The lift install wasn't too bad if you're familiar with taking off struts and springs. The hardest part was dropping the rear subframe to add the spacers.