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      07-26-2012, 01:19 PM   #67
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Quote:
Originally Posted by beta View Post
The Star Specs are known for running wide even though they have the same spec width. That's probably why they rub and the PSS don't.
.......
The other intangible factor is the shoulder profile.
Some tires (starspec) have a more squared off shoulder & others are more rounded; with the same section width.
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      09-04-2012, 11:20 PM   #68
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I just put stock size 225/255 PSSs on my stock //M wheels.
The sidewalls look funny on the fronts. The rear sidewalls are pretty much straight vertical. The front sidewalls curve in toward the car from the rim to the road, like they had to be stretched to fit the wheel width.
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      09-05-2012, 01:47 AM   #69
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Stickmon, what tires were you running before? And what is the full size (sidewall profile) of the 225 front?

The PSS doesn't have the square sidewall of, say, a Star Spec. But it shouldn't have the stretched tire look IMO.
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      09-05-2012, 12:47 PM   #70
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Stock size 225/45-18 front 255/40-18 rear.
Had Hankook V12s on it before.

Front:

Name:  Photo-0009.jpg
Views: 999
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Rear:

Name:  Photo-0012.jpg
Views: 878
Size:  128.6 KB

Last edited by StickMon; 09-05-2012 at 03:47 PM..
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      09-05-2012, 02:42 PM   #71
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Quote:
Originally Posted by StickMon View Post
Stock size 225/45-18 front 255/40-18 rear.
Had Hankook V12s on it before.
Post up a pic. Sounds odd.
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      09-07-2012, 11:41 PM   #72
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Looks about what I'm seeing with my PSSs. The sidewall is more rounded. I think it's more pronounced with the 225/45 vs. 255/40. Guess we'd need more folks with stock size tires to comment on what they see to know for sure. But it doesn't look too far off from what I'm seeing.
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      09-07-2012, 11:57 PM   #73
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Thanks for the confirmation. I think that funky ridge just off of the bead makes it look stranger than it is.
Next time around I might do 245/40 front and 275/35 rear, just to see how I like it.
Word from others is that there's no rub if not lowered.
Some have done 265/35 rear, but I think that deviates a little too far from stock diameter.
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      09-13-2012, 07:46 PM   #74
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Quote:
Originally Posted by StickMon View Post
Stock size 225/45-18 front 255/40-18 rear.
Had Hankook V12s on it before.

Front:

Attachment 746272

Rear:

Attachment 746269
Quote:
Originally Posted by Finnegan View Post
Guess we'd need more folks with stock size tires to comment on what they see to know for sure. But it doesn't look too far off from what I'm seeing.
Yep, i checked mine closely tonight and the curvature difference is the same on mine as well. i have the stock sizes. I dont even need to take a pic of it, its the same i see in your pics.
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      09-22-2012, 06:06 AM   #75
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I went with 265/40/18 rears for the PSS.
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      09-22-2012, 05:58 PM   #76
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Just put a set on the back at 265/35-18. Noticably more grip than the outgoing NT-05s in the corners. Very impressive so far.
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      09-26-2012, 03:32 AM   #77
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It is finally about that time... On stock wheels and suspension I have narrowed it down to these options..

1. 245/40 (front) 275/35 (rear)
2. 235/40 (front) 265/35 (rear)


My gut tells me to go with #1 as long as there will be no rubbing issues..

Thanks for all the info on these tires.. I am sooooooo looking forward to getting those contis off my ride.. This forum rocks!!
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      09-26-2012, 11:45 AM   #78
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I'm running #1, and lowered about 0.5" I have no rubbing. However for a stock m I might recommend you go with a third option:

245/265

The reason is with the 275s I don't often break traction on acceleration. Additional grip can actually slow you down.

After I put in the 3.91 r&p in I'll decide If I stay with 275 rears or bump it down next time I need tires. If you plan on supercharging and/or 4.10s then stick with option #1.
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      09-26-2012, 03:00 PM   #79
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I'll add a little feedback on running the 245/40 275/35 (vs. old Star Spec 235/40 265/35 combo on stock wheels.

As Kgolf (and The Hack, and others) pointed out, this is may be too wide for the stock wheels, especially on track (and maybe more so with Michelins given the rounded vs. Star Spec square design). Technically it's within the recommended rim size range, but there were issues for me. And this may be more of a track-use related thing vs. a street use thing.Confounding Factors
Lower profile sidewall on Star Specs
~700 miles on the PSS, maybe not fully "broken in".
Results
Significantly less grip in braking, in, and out of corners
DSC was very active. ( I usually run with it on for the first lap, maybe the first session, but had to leave it on this day.)
DSC active in corners (no traction rolling on to throttle at apex) where I roll on full throttle and never have issues.
More front end slip--understeer
Understeer in, oversteer out
No confidence!
Lap time off by 7 seconds (same alignment settings as usual too)
Temp on the middle of the tire tread was 30+ degrees hotter than the inside or outside readings on all 4 tires using an IR gun (my friend had an IR gun, but no pyrometer). Contrast that with my friend's even temps across the tire, and Skelekitty's more even tire temps.
Notes
For those thinking it might have been an "off" day, I took out Skelekitty's car, with 2.5 year old Star Specs that have seen 7 track days and 15,000 miles (pretty heat-cycled and hard) and was 1 second off my usual time. Our cars are identical, same suspension, alignment, mods.
I really didn't notice much difference on the street (I don't drive anywhere near how I do on track), but there's a big difference on the track.
Plans
I'm going to mount these on wider wheels (9/10) and give that a shot. I had planned to do this before my track day, but life got in the way.

Last edited by Finnegan; 09-30-2012 at 02:06 PM..
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      09-26-2012, 09:17 PM   #80
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A lot of good info here.. Thanks guys.. I still don't know what I am going to do....

Last edited by MHeavNC; 09-27-2012 at 08:20 AM..
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      09-28-2012, 01:03 AM   #81
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Mine's a DD. I drive at least 3 hours/day and manage to make a light and throw it around a corner once or twice a day.
Just put the stock size on, so it'll be a little while. I'm thinking about the 245/40 275/35 PSSs on the stock wheels just as a hoot and for the look.
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      10-29-2012, 11:10 AM   #82
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Discount Tire and Michelin were running a $70 rebate on Michelin tires this past Friday and Saturday so I got a set of Pilot Super Sports on Saturday afternoon. I went with 245/40-18 front and 275/35-18 rear since they're closer in circumference to the stock tires than the 235/265 combo and are within the Michelin specs for rim width.

I asked them to test fit the rear tires first since my car has H&R Sport Springs. The previous owner had 19" wheels with tires that were too large and rubbed the inner fender wells on both sides and actually wore through the fender liner just inside the left fender arch. He put the original wheels and tires back on the car when he traded it in to the dealer I bought it from. The original tires were 6.5 years old. I calculated that total mileage on the tires is only about 3300 miles, but I'd rather be safe than sorry.

The installer said clearance would be no problem and I can't really see that the clearance in the rear is any less.

Our local BMW CCA chapter had an autocross yesterday that I ran in. It was my first timed autocross in this car, so hard to draw any comparisons with the original tires. During a hard right hand turn in one portion of the course I thought I heard some rubbing on the left rear, but I don't expect to experience this kind of braking, acceleration and turning on the street.

Other than that, I only drove a few miles home from the tire store and was mostly on the freeway to and from the autocross. I'll check back in with more feedback in a few weeks.
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