Hi all, I have a 2013 ISF (completely stock) and it's time for replacement tires. I've searched and read through the hundreds of posts on ISF tire sizes. A lot of the threads were older and covered mostly to '08'-11' models, so now that folks have tried out more tires/sizes, I was hoping to see if there's any updated info/consensus.

I'm partial to Michelin tires (PS4s) and was thinking of upsizing. I typically like a less floaty car feeling and would like to maximize handling. This is my DD. My questions are:

1. Is 245/35/19 and 275/30/19 still the recommended size to move to?
2. Will turn-in/handling feel looser or more precise?
3. I'm in the Los Angeles area -- has anyone had issues running these size tires in the area (potholes, etc.)?
4. Any downsides to moving to 245/35/19 and 275/30/19 that I should know about?
5. What would be different if I moved to a 255/35/19 front?

Thanks in advance!

 

1. yes
2. more grip but since its wider probably not noticeably less precise since the width of tires are okay for the rim widths. stock is undersized
3. no issues, you can run slightly taller than OEM sizing which will help with potholes if you want.
4. they're more expensive than stock tires sizes but that's mostly it. most people move to these sizes after stock
5. you would get less understeer with more front grip, but turn in might be a bit slower since 255 on 8.5" is slightly bulge (more floaty)

 

After a few sets of 30’s on the rear, I moved them up to 35’s

No regerts…!! and it’s definitely more comfortable on LA roads and fwys.

Joe Z

 

I run 255/35/19 front and have run both 275/39 and 275/35 PS4S on 2014 wheels. I also have the latest steering ECU, and it makes a significant difference. You already have this in your 2013, so that part is done. This setup does not feel floaty, and turn in is more crisp than the OE sizes. I run PS A/S3+ in the winter in stock sizes on my 2008 wheels, so I have a pretty direct comparison twice a year. The car unquestionably brakes better with 255s in front and the difference is substantial.

 

Thanks for the feedback so far! Sounds like 255/35/19 and 275/30/19 might be the way to go. (Leaning towards 275/30 since I'm in a suburb of Los Angeles, so the roads aren't quite as bad as when I used to be in downtown). Would this setup look okay on stock suspension?

 

It looks like this:

 

That looks amazing (and like my exact car, except for your coated rims). I'm reading in one of your prior posts that if Michelin made 285/30/19's you would try them out - it looks like on TireRack that Michelin now has that size (although backordered). Did you ever get a chance to try out the 285s?

 

No, but if they make them now I'll try them out.

 

I have an 2008 on 2008 OEM wheels (I believe they narrower than the 12-14 OEM wheels) and oem suspension - I run Michelin PS4S 245/35ZR19 Extra Load on front and 255/35ZR19 Extra Load on the rear.

Upgrading the front tires to a wider size really helped on this heavy car - I did not upgrade the rear as I did not want the car to keep understeering.

 

Mine oversteers just fine with 255/275 combo. I did it just today in the rain for fun.

 

For comparisons sake here is (a photo) the 255/35 and 275/35 set up slightly lowered on coilovers..

the thicker rear sidewall helps the overall comfortable ride for ME




Joe Z

 

One more question - how should I think about reconciling the 245/275 and 255/285 recommendations with the below (from another thread)? At 255/285 (the current size I'm leaning towards) on the Indy 500s, it looks like tread width is 9.1"/10.3", which is wider than my stock wheel widths by .6"/.8". Thanks!

 

Any rubbing?

 

All good info there, but keep in mind, we have very heavy cars here. 3800+ pounds in stock form is far from light. The OE tires (I know this from experience) get greasy on the last two or three laps of a 20 minute session requiring the driver to slow down. Our biggest problem is available wheel widths without going full custom. I've been told by Supra track guys they run best with 315s on all corners and those are 3400 pound cars. While there's a lot of useful analysis in the article, a whole lot of it is academic for our application because we have wheel width limitations and wheel well size limitations far below what we would ideally have for a car this weight. As an example - I had an '05 Scion tC, it weighs about 3100 lbs, and when I put Toyo 245s with 8 1/2" rims on it, I was cornering 6 mph faster than my Supra on the OE sized Michelins specifically made for the Supra. Supras came with slightly stretched tires - 9 1/2" rear rims with a 255/40/17, so Toyota figured out what was going to best work on that car and it follows the MotoIQ article's premise.

Also, most importantly, you're not going to get the tires up to temperature on the street. You can get the rears up to temp by spinning them, but you'll never see all four tires at ideal operating temperature on a street drive. The discussion points in the article are most applicable to track driving. On the street, as you can see by the hellaflush picture in the article, you can get away with a lot of things for fashion that would not survive even a few laps at the track.

 

Thank you, lobux, for the extremely helpful thoughts. I'll give the 255/285's a shot!