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      08-03-2019, 05:15 PM   #1
eggman51
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Michelin Pilot Sport Cup 2 Tires - could use some guidance

I have Apex ARC-8 wheels in 18 x 9 x ET30 and 18 x 10 x ET25.

I had to use a 5mm space on the fronts to clear my AP Racing BBK (only needed 3mm but could only track down a 5mm spacer at the time).

Suspension is stock.
I plan to do a coilover upgrade in the future.
Fenders are not rolled.

I currently have Michelin Pilot Sport 4S tires with 245/35 and 275/35. The 275/35 rubs on the rear slightly under cornering load.

I had 2 um... incidents.. in may last track day and unseated the bead on the front tires. Twice A bit silly but I'm still figuring this beast out. I ended up driving about 300m and 1km on the unseated front tire to get back to the pits. I was advised by a trustworthy source that these tires should not be used on the track after this as the sidewall damage could make them prone to failure.

I need tires I can drive to and from the track, but I am planning to buy a second set of wheels so I can swap track specific tires on before heading to the track.

I am looking at buying some Michelin Cup 2 tires. Am considering:
245/40
265/35

What I wondered about was:
265/35
285/30
w rolled fenders

Also was wondering if the 245/40 will rub, and should I be considering 245/35 on the fronts?

Thanks in advance for any help you can provide.

Cheers,
Eamonn
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      08-03-2019, 08:33 PM   #2
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245/40 won’t rub and that’s what you should’ve run to begin with. 245/35 is way too short... (1.3” shorter than stock)

But I wouldn’t bother switching to cup 2’s until you’re ready to dial in some camber or you’ll chew up those fronts really fast.

And for the price not sure how much value you’ll get. I’d look at RS4 or Z3’s first unless you really think you need r-comp grip (and honestly the hankook and Dunlop’s won’t be that much slower).
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      08-04-2019, 03:25 PM   #3
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I believe current front camber is -3 degrees, and rear is -2 degrees. I used a Turner shim kit to accomplish this. Should there be more than that? Tough to get there without after market parts as I think I am out of adjustability at this stage.

I find the car to be pretty neutral in handling, but does exhibit a bit more medium speed under steer than I like. Note that I am still really early in learning to drive the car properly.

The 245/40 size for the fronts sounds good. I went with the 245/35 based on advice from Apex when I bought the wheels. Should I be considering a 255 front tire?

For the rears, given there is some rubbing should I be looking at 265 or get a fender roll and go with 275 or even 285?

I will definitely look at the other tire suggestions - much appreciated.

Also.. just wondering if you think there is in fact cause for concern with the tires having been driven for about 1300 meters / yards with the front bead unseated.

Thanks so much - your advice is much appreciated.

Cheers,
Eamonn
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      08-04-2019, 04:21 PM   #4
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Quote:
Originally Posted by eggman51 View Post
I believe current front camber is -3 degrees, and rear is -2 degrees. I used a Turner shim kit to accomplish this. Should there be more than that? Tough to get there without after market parts as I think I am out of adjustability at this stage.

I find the car to be pretty neutral in handling, but does exhibit a bit more medium speed under steer than I like. Note that I am still really early in learning to drive the car properly.

The 245/40 size for the fronts sounds good. I went with the 245/35 based on advice from Apex when I bought the wheels. Should I be considering a 255 front tire?

For the rears, given there is some rubbing should I be looking at 265 or get a fender roll and go with 275 or even 285?

I will definitely look at the other tire suggestions - much appreciated.

Also.. just wondering if you think there is in fact cause for concern with the tires having been driven for about 1300 meters / yards with the front bead unseated.

Thanks so much - your advice is much appreciated.

Cheers,
Eamonn
Sorry man but your post in general seems to be all over the place (and it's not clear to me at least) what's wrong with your current setup and what you're trying to accomplish. Basic questions...

1. Why are you looking at the Cup 2s (as opposed to other brand/models)? What's wrong with the PSS you have now (if its just a matter of replacing the fronts)?

2. Why are you looking to change fitments? What's wrong with what you have now (other than the fronts running an undersized sidewall)? If you find the car to be pretty neutral with a hint of understeer, upsizing your rears will only exacerbate the issue.

3. If you know coilovers are coming, that will affect your tire fitments so would you rather buy for what you have now or plan to do later?

4. How'd the front tire get unseated to begin with? Going two off and picking up dirt is very different from sliding sideways. If the former, I'd see if a shop can just rebead using sealant and pay attention to pressures. If it's not 'fixable', then I wouldn't run them at all.

If you’re “still figuring out this beast” as you say, I would think you’d want to continue running street tires before looking at more aggressive compounds where incidents can become more costly? Plus by then you’ll know what suspension you’re running do you can optimize everything together.
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      08-04-2019, 06:38 PM   #5
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Quote:
Originally Posted by 3002 tii View Post
1. Why are you looking at the Cup 2s (as opposed to other brand/models)? What's wrong with the PSS you have now (if its just a matter of replacing the fronts)?
I've always thought Michelin made great tires, and the Cup 2s seem to be considered very good (albeit quite pricey).

I have been considering purchasing a second set of wheels, and swapping out track day tires for the drive to, and at, the track. The thinking being that the PS4S tires become my street tires, with something more track specific on another set of wheels for track days.

You bring up a good point, maybe I will just replace the fronts with another pair of PS4S tires. I had always though all 4 tires should be replaced at the same time if there is reasonable wear on any of the axles??


Quote:
Originally Posted by 3002 tii View Post
3. If you know coilovers are coming, that will affect your tire fitments so would you rather buy for what you have now or plan to do later?
How much would this affect tire size and choice? Would it affect wheel choice or just possible spacer requirements?

Quote:
Originally Posted by 3002 tii View Post
4. How'd the front tire get unseated to begin with? Going two off and picking up dirt is very different from sliding sideways. If the former, I'd see if a shop can just rebead using sealant and pay attention to pressures. If it's not 'fixable', then I wouldn't run them at all.
It was a spin and 4 wheels off excursion that unseated the left front bead. I have to drive about 300m back to the pits. It was re-seated it at the track and I kept going. Then uh.. the next day I had another 4 wheels off excursion.. I had to drive about 1km back to tbe pits, and the left front had been unseated again. It was re-seated at the track and I drive it ~500km home without issue.

I was advised the fronts should not be used as track day tires after this much driving flat / damage to the sidewall.

I realize two 4 wheel excursions in two days is a bit daft, but one was (an over-reaction) to avoid a spin in front of me, and the other.. welp.. I thought I could take a particular bend flat out, but the laws of physics disagreed.

Quote:
Originally Posted by 3002 tii View Post
If you’re “still figuring out this beast” as you say, I would think you’d want to continue running street tires before looking at more aggressive compounds where incidents can become more costly? Plus by then you’ll know what suspension you’re running do you can optimize everything together.
Yeah, this does make sense, and I very much appreciated the words of wisdom!

At this point I am thinking to get a set of PS4S fronts in 245/40/18, then next season get another set of track day tires and wheels at some point.

Cheers,
Eamonn
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      08-04-2019, 09:17 PM   #6
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Quote:
Originally Posted by eggman51 View Post
I've always thought Michelin made great tires, and the Cup 2s seem to be considered very good (albeit quite pricey).

I have been considering purchasing a second set of wheels, and swapping out track day tires for the drive to, and at, the track. The thinking being that the PS4S tires become my street tires, with something more track specific on another set of wheels for track days.

You bring up a good point, maybe I will just replace the fronts with another pair of PS4S tires. I had always though all 4 tires should be replaced at the same time if there is reasonable wear on any of the axles??




How much would this affect tire size and choice? Would it affect wheel choice or just possible spacer requirements?



It was a spin and 4 wheels off excursion that unseated the left front bead. I have to drive about 300m back to the pits. It was re-seated it at the track and I kept going. Then uh.. the next day I had another 4 wheels off excursion.. I had to drive about 1km back to tbe pits, and the left front had been unseated again. It was re-seated at the track and I drive it ~500km home without issue.

I was advised the fronts should not be used as track day tires after this much driving flat / damage to the sidewall.

I realize two 4 wheel excursions in two days is a bit daft, but one was (an over-reaction) to avoid a spin in front of me, and the other.. welp.. I thought I could take a particular bend flat out, but the laws of physics disagreed.



Yeah, this does make sense, and I very much appreciated the words of wisdom!

At this point I am thinking to get a set of PS4S fronts in 245/40/18, then next season get another set of track day tires and wheels at some point.

Cheers,
Eamonn
I run cup 2's and they're decent but not worth their sticker price. I got mine on discount but would not buy them at MSRP. I would much rather stick to a 200tw tire for same price (e.g. RS4 or RE71R).

If you're still figuring out the car and finding yourself caught in "oh shit" moments on track, I would think you'd want to stick to a sticky street even longer. R-comps will break traction w/ less warning. You should be thinking of moving to a grippier tire when you've outdriven your current tire but doesn't sound like that's the case with PS4S. Plus nowadays, most of those 200tw "cheater" tires are within close distance of R-comps but offer better wet traction anyway.

Coilovers will likely offer more strut side clearance meaning you can stuff wider rims and wider tires. It's surprising that Apex would even suggest a 245/35-18. I've seen them recommend 245/40 and 255/35-18 for front but never a 245/35.

Re the rears, keep in mind a 265 in one compound maybe equal to (or even greater) than 275 in another so you shouldn't focus on certain #. Figure out your rim size, tire compound, suspension settings (ride height, camber, caster), and then worry bout what's the most you can stuff. 265 square works well for everyone but if you're sticking to staggered, then 245/265 and 255/275 are popular choices but again you really need to figure out those other limiting factors first.
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      08-04-2019, 10:39 PM   #7
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Agree with all the comments already posted. One thing that I would emphasize is moving to a square setup. Doing so will give you a better balanced car and also allow you to extend the life of whatever tires you decide to buy.
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      08-04-2019, 10:51 PM   #8
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Great feedback - thanks!

I have ordered a replacement set of PS4S fronts only in 245/40. This is the cheapest and most sensible solution for now - thanks for helping me realize that!

I went back through my emails with Apex, and confirmed they recommended 18 x 9 - 245/35 and 18 x 10 - 275/35, which contradicts their advice on their fitment guide for the Z4.

I've read up some more on suspension options and wheel / tire choices, so I better understand that now - thanks!

WRT still learning, this is definitely the case, but I've been able to turn some good lap times (1.59.8 at The Ridge - 2 flat is a good time in a Z4 there) after 4 track days, and getting into the 2.03s at Oregon Raceway Park CCW after 1 track day (2.01 is a good lap time here in the CCW config). Not trying to brag at all, just saying that "oh shit" moments are happening at a reasonable pace.

Quote:
Originally Posted by Azeka1 View Post
One thing that I would emphasize is moving to a square setup. Doing so will give you a better balanced car and also allow you to extend the life of whatever tires you decide to buy.
Regards square setups, can you do that with different width wheels, but even up the tire sizes? Or must you use the same size wheels?

Thanks again for your patience and help - much appreciated - I hope I can buy you a beer or ten someday!!!
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      08-05-2019, 12:13 AM   #9
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Quote:
Originally Posted by eggman51 View Post
Great feedback - thanks!

I have ordered a replacement set of PS4S fronts only in 245/40. This is the cheapest and most sensible solution for now - thanks for helping me realize that!

I went back through my emails with Apex, and confirmed they recommended 18 x 9 - 245/35 and 18 x 10 - 275/35, which contradicts their advice on their fitment guide for the Z4.

I've read up some more on suspension options and wheel / tire choices, so I better understand that now - thanks!

WRT still learning, this is definitely the case, but I've been able to turn some good lap times (1.59.8 at The Ridge - 2 flat is a good time in a Z4 there) after 4 track days, and getting into the 2.03s at Oregon Raceway Park CCW after 1 track day (2.01 is a good lap time here in the CCW config). Not trying to brag at all, just saying that "oh shit" moments are happening at a reasonable pace.

Quote:
Originally Posted by Azeka1 View Post
One thing that I would emphasize is moving to a square setup. Doing so will give you a better balanced car and also allow you to extend the life of whatever tires you decide to buy.
Regards square setups, can you do that with different width wheels, but even up the tire sizes? Or must you use the same size wheels?

Thanks again for your patience and help - much appreciated - I hope I can buy you a beer or ten someday!!!
I have moved to a square setup of 265/35-18 w 200tw tires. 18x9.5 et35 square is a common setup which is what I have. With 5mm and 12mm spacer and stud conversion, it's pretty good setup with wet traction to drive to and from the track.

I chose Falken RT615+ when it first came out with $95/tire to try my first 200tw square setup. So far so good drive to Ridge in the rain. White knuckle moments of driving NT01 in the rain in the past on hwy 101 can't be the said the same.

The clearance is also a limitation when choosing your coilover setup specially on the front. The progressive spring limited the 9.5 width and 265/35 tire combo so KW V3 was out of the question hence I chose the Status coilover as an experiment.

You can definitely ride in it when we meet up.
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      08-05-2019, 08:04 PM   #10
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For now I am just replacing the fronts to be cautious and staying with a staggered setup.

I think I have an idea what I will do to preserve my existing investment in wheels, but make the switch to a square setup.

My car is a daily driver, and I drove it all through the winter last year. If it snows heavily, I can borrow a family members car (they are all 4 wheel drive) or just work from home.

My current wheels are Apex ARC-8
18 x 9 ET30
18 x 10 ET25

What I think I will do is go:
WINTER: 18 x 9 ET30 with Pirelli Sottozero 3 255/35 [or 245/40] winter tires on all 4 corners
SUMMER: 18 x 10 ET25 with Michelin PS4S 275/35 tires on all 4 corners

I realize the summer setup will require rolled fenders, camber plates, aftermarket suspension, and possibly 5mm spacers up front. I was planning to do the suspension anyways, and I arelady needed the spacers to clear my BBK.

This way I get to keep my existing wheels, buy another set like it, and split them into 2 squared up sets.

If I continue to find throwing money out the window of a moving vehicle compelling, one day I might get a 3rd set of tires and wheels more dedicated to track use.

Thanks for all the help - so much appreciated!

Cheers,
Eamonn
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      08-06-2019, 02:12 AM   #11
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Quote:
Originally Posted by eggman51 View Post
For now I am just replacing the fronts to be cautious and staying with a staggered setup.

I think I have an idea what I will do to preserve my existing investment in wheels, but make the switch to a square setup.

My car is a daily driver, and I drove it all through the winter last year. If it snows heavily, I can borrow a family members car (they are all 4 wheel drive) or just work from home.

My current wheels are Apex ARC-8
18 x 9 ET30
18 x 10 ET25

What I think I will do is go:
WINTER: 18 x 9 ET30 with Pirelli Sottozero 3 255/35 [or 245/40] winter tires on all 4 corners
SUMMER: 18 x 10 ET25 with Michelin PS4S 275/35 tires on all 4 corners

I realize the summer setup will require rolled fenders, camber plates, aftermarket suspension, and possibly 5mm spacers up front. I was planning to do the suspension anyways, and I arelady needed the spacers to clear my BBK.


Eamonn

255 square is a very poor choice for snows. I’d go 235 square on 8.5 or 245 if you’re trying to preserve your 9s. Heck you can even run factory 225/255 snows on the oe wheels and sell your pair of 9’s if you’re trying to stay within a budget
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      08-06-2019, 10:56 AM   #12
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Good to know - thought that might be the case - will go 245/40 so I can use my 9 inch ARC-8s. That's actually a lot cheaper for those size tires.

I don't have the factory wheels, it came with aftermarket 19s which look great, but I prefer the 18s for several reasons.

I think this thread saved my a couple grand

Cheers,
Eamonn
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