: 255/50/17 on the STS



Vince59
06-24-09, 10:20 PM
I did it, I put the Kumho Ecsta ASX 255/50/17 on my 08 STS4 and I am impressed, the car feels and tracks better, the turn in is outstanding and while attacking a tight on ramp the car no longer feels like it wants to roll over the sidewalls. I would now say the handling of this car is very close to that of my 03 CTS with the FE3 suspension.
I should also get the added benefit of added protection from Chicago's potholed streets.

The other benefit is the car now has tires on it that fit the car, as the tires do increase the height by .39 in and the width by .78 in. over the stock Michelins.

Before and after pics.

amgqmp1
06-26-09, 10:42 PM
I seriously appreciate you sharing your experiences so far. I've been considering this for most of the same reasons.
You're right on that it looks much better too.

Have you noticed much variance in the speedo?

next2pool
06-27-09, 02:03 PM
Two months ago I put original staggered size Kumhos on mine and have been very happy with them except for one issue. Since I don't drive the car everyday, they flat spot after sitting and cause quite a disturbance for the first couple of miles. They smooth out perfectly, but I have almost forgotten what flat spotting was since the advent of radials. Surprisingly, I'm finding that flat spotting is indeed becoming an issue again with modern radials. My new BFG radials on my motorhome do the same thing even though the previous Michelins never did. Others are finding the same problem.

WorkinWoodWheel.TX
06-29-09, 01:52 PM
Did you put those on all 4 tires?

aintmisbehavinn
06-29-09, 07:57 PM
Looks great, really filled up the fender wells..

Vince59
06-30-09, 08:30 PM
I seriously appreciate you sharing your experiences so far. I've been considering this for most of the same reasons.
You're right on that it looks much better too.

Have you noticed much variance in the speedo?
I haven't put it on the GPS yet, but according to the tire calculator my is 2.9% slow. So at 60 mph I should be showing 58.2 mph on the speedo.
http://www.1010tires.com/TireSizeCalculator.asp?action=submit


Did you put those on all 4 tires?
All 4 tires were changed to the 255/50/17

The more I drive the car the happier I am with my decision to make the change, the steering feels faster, it feels like there is less body roll on quick lane changes and while cornering.

I was concerned about trying to out think the engineers who spec'd the tires on this car but this change/upgrade has transformed the car for the better, and most importantly I'm not cringing everytime I see buckled or broken pavement, the 235's were to small for a large car like the STS and were overmatched in all but the smoothest conditions and most sedate driving.

Vince

bass_sts
07-01-09, 01:21 PM
I had the Kuhmos before, I just got the Michellins a/s sport plus, these are quieter. I felt the Kuhmos had less than acceptable grip (specially in the rain). The michs are more expensive but I will should get better wear from them.

Also, anyone (or everyone) else seeing the inside wear on the fronts. I was at the shop changing the tires and another STS was also getting new shoes. Same wear.

megeebee
07-07-09, 01:39 PM
Thank you for posting this. I may do the same thing when my 2005 needs a set of tires.

The size you used certainly addresses one of my pet-peeves in the appearance of the STS. The standard 17" wheels, and the tires specified by the factory, make the car look like a Zeppelin riding a skateboard. The tires you've used fill the wheel-openings much more completely and, as you say, make the car sit higher. This is a great aid in making the car look more like the designers intended.

I went to the expense of buying a set of 18" factory wheels for my car (it has the same 17" that yours does), but now I'm wondering if I shouldn't sell them and simply use the same size tires as you have.