Subaru WRX Forum banner
1 - 18 of 18 Posts

·
Registered
Joined
·
237 Posts
Discussion Starter · #1 ·
The WRX comes w/ the factory tire size of 205/55/16 however how much would it change the cars looks, performance, readings, by just switching to the lower sidewall number of 50 from 55? My car is off by 2mph at 70mph from the factory tire.

Pros:
Lower & stiffer sidewall thus better handling
Less wheels to move thus faster 1/4s & 0-60s

Cons
Odometer is actually more than what was driven
Speedometer is reading higher than actual speed
Looks

Bsacially are there any real negative benefits from using the 50 vs. 55 in the performance sector? Also does it look bad because I'd still be using the stock rims on a lower profile tire so would it look like crap w/ not alot of rubber? I'll be getting the RE730s in any case but I can pick from the 2 different sizes. I really want the best handling tires ( less roll ) and can deal w/ the "increase in mileage and off odometer." Any ideas? Thanks. :)
 

·
Registered
Joined
·
126 Posts
chuglobal said:
The WRX comes w/ the factory tire size of 205/55/16 however how much would it change the cars looks, performance, readings, by just switching to the lower sidewall number of 50 from 55? My car is off by 2mph at 70mph from the factory tire.

Pros:
Lower & stiffer sidewall thus better handling
Less wheels to move thus faster 1/4s & 0-60s

Cons
Odometer is actually more than what was driven
Speedometer is reading higher than actual speed
Looks

Bsacially are there any real negative benefits from using the 50 vs. 55 in the performance sector? Also does it look bad because I'd still be using the stock rims on a lower profile tire so would it look like crap w/ not alot of rubber? I'll be getting the RE730s in any case but I can pick from the 2 different sizes. I really want the best handling tires ( less roll ) and can deal w/ the "increase in mileage and off odometer." Any ideas? Thanks. :)

We get 17inch rims as standard (same design as yours) and we have 215/45/r17's. brigdestone RE011's
 

·
Registered
Joined
·
310 Posts
I love Bridgestone RE's . I burned thru a few sets of RE71's back in
the autox days.

Chuglobal, using a smaller tire will of course lower your 1/4 but kill
some of your top end. Also you will be revving higher on the
highway. Small price to pay to go QUICK :D
 

·
Registered
Joined
·
237 Posts
Discussion Starter · #4 ·
Humm ...

I didn't know that :(.
 

·
Registered
Joined
·
310 Posts
Let see, when you reduce the diameter of the tire by going from 50
to 55. You can see the height of the tire/rim is lowered. Your actual
diameter is reduced and with that also is your revolution. It is
almost like using a lower gear on the bike.

The way to go is to get 17 inch rim and go 55 which will allow you
to retain the factory tire/rim height. Since we don't have traction
problem with the rex, wider tire will only help in corner hugging but
might slow down your ET.

As I remebered on F1 and Nascar , narrow tire gives top end but
less grip for the turns and visa versa. Remeber roll resistance
matters.

Since you are not running Solo 2 or canyon runs, you should stay
with oem size and get a summer tire like the BS REs or Kuhom.

btw my brother with the auto rex was shocked how fast mine rex
is with the MBC. Now he wants one :D
 

·
Moderating on the run!
Joined
·
7,322 Posts
Reducing tire diameter effectively reduces your overall gearing. You will be shifting sooner (reaching redline quicker), not necessarily a bad thing depending on what the situation is. You will lose very top end- although how often are we going 140mph?

Tire construction will have more to do w/ sidewall stiffness than reducing your sidewalls less than a 1/4 " (5mm).

Just a couple of things to consider.

Big Sky
 

·
Registered
Joined
·
42 Posts
My thoughts are that a 205/50 tire will look small on your WRX. If you like the 50 series, maybe go with wider tire like a 225/50. You will get that stiffer sidewall and the tire will still look very "meaty". It's been said that 225 on a 6.5" rim is not ideal, but there are a few who are happy with that size. There is also the KDW that comes in an in-between 215/50 size. When I replace the tires on my stock wheels I plan to go with the stock 205/55 and just get a good Z rated performance tire. :D
 

·
Registered
Joined
·
424 Posts
I agree with NOSS on this. However everyone else has a valid point as well.

Personally, I think it would look funny if you JUST lowered the profile. I think it would be better to get like a 215/50/16, this SHOULD be close to the current diameter of the wheels so you shouldn't have to worry about your speedo/odo. I think a 225 is too wide for the rim, but not sure.

I don't think the lower profile will help very much in 1/4mi times (maybe a little, but so does taking a crap before you run). But for sidewall handling, the 215/50 would work better.
 

·
Moderator
Joined
·
1,377 Posts
jmussetter said:
I don't think the lower profile will help very much in 1/4mi times (maybe a little, but so does taking a crap before you run).
Dude, you had me cracking up at work. =)
 

·
Premium Member
Joined
·
6,750 Posts
I'm running 225/50/16s on the stock wheels and they seem to work just fine. I haven't noticed any problems at all.
 

·
Registered
Joined
·
310 Posts
Verdugo said:
I'm running 225/50/16s on the stock wheels and they seem to work just fine. I haven't noticed any problems at all.
Great thx for the info. Is that +2 setting ? If it fits the oem rim and
doesn't hit the fender then I am in heaven. I am a corner hugger,
I love fat tires and shocks and springs and sway bars :D

Now that the engine mod is half way done, time for some corning
mod :D
 

·
Premium Member
Joined
·
6,750 Posts

·
Moderating on the run!
Joined
·
7,322 Posts
Plus (or negative for that matter) sizing is increasing (or decreasing) rim size by one inch w/o effecting overall tire diameter. Thus +1, +2 or -1 etc.

Big Sky
 

·
Registered
Joined
·
14 Posts
Correst re the definition ont he plus sizing. Going to 225/50/16 is not considered a lus sizing as you are still in the same rim diameter. I have the 225/50/16 Bridgestone s03's. They are recommended for rims of 6 inch to 8 inch width. Our stock rims are 6.5 inch, therfore no problem. By the way the s03's are SOOOOOO sticky it is sick
 

·
Registered
Joined
·
310 Posts
Hmm, from what I read, plus size have something to do with replacing
the oem tire to a wider or narroer tire without changing the actual
height of the wheel.

So if stock is 195 then 205 should be +1, 225 might be +2. I think
they have a right up on tire rack also.
 
1 - 18 of 18 Posts
Top