Orthojoe's track build journal
11-09-2015, 10:20 AM
#1501
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With Cup 2, my current targets are 32 F and 34 R.
11-09-2015, 11:07 AM
#1502
Nordschleife Master
Thread Starter
I looked through my owner's manual as well as on the Michelin site for that recommended pressure and could not find anything. Would you be able to point me in the right direction? From this I take it those very used, take off tires then? Could the front wear be corrected by lowering the hot pressure at the expense of more understeer?
https://rennlist.com/forums/991-gt3-...endations.html
Yes, the dunlops were takeoffs. However, they only had 100 street miles on them. They still looked and smelled brand new when I got them.
I thought about tire pressure being too high, but the outer blocks are less bulky than the cup2, which is why I think they need more pressure than cup2. Also, the outer edges still have increased wear. You could be right, though.
The cup2 center tread seem to wear like this as well, but not as pronounced.
11-09-2015, 11:09 AM
#1503
Nordschleife Master
Thread Starter
Originally Posted by hlvg
Great videos, very smooth driving!
The guy in the Lotus took his time to move awayÂ…
It'd be great if you could point the outside camera towards the back to get an idea of how fast you pull away from some of those carsÂ…
The guy in the Lotus took his time to move awayÂ…
It'd be great if you could point the outside camera towards the back to get an idea of how fast you pull away from some of those carsÂ…
11-09-2015, 12:00 PM
#1504
Three Wheelin'
This is where the info came from:
https://rennlist.com/forums/991-gt3-...endations.html
The cup2 center tread seem to wear like this as well, but not as pronounced.
https://rennlist.com/forums/991-gt3-...endations.html
The cup2 center tread seem to wear like this as well, but not as pronounced.
Agree on this Joe. The Cup2 have a similar center tread block design, which I assume is for wet performance (2 center channels). This wear is likely from trail braking at turn in, the center blocks squish over and show much more wear on one side. The treadwear rating of the Cup2s makes this seemingly wear closer to the same rate as the outer shoulders, and with the Dunlops, it shows a significant inner block asymmetrical wear pattern. The TrofeoR and old Cups didn't have this design pattern, and they are not so great in the wet.
11-09-2015, 12:25 PM
#1505
Looks like Michelin removed that info from their site. It now has a place holder:
INFLATION PRESSURE ADVICES
Information will be updated soon.
I found similar heading, wording on the German and US site.
11-09-2015, 09:00 PM
#1506
Nordschleife Master
Thread Starter
2) slicks/r7/r6/etc aren't available in the sizes you would need for stock wheels
===> you just need more wheels
3) 19" wheels require some small modifications and the clearance between the wheel and the rear LCA is uncomfortably small to me
===> small mod that takes a plier to do, i have 19" with plenty clearance. i fitted them no the car, not just based on calculations.
4) If I do run slicks, I won't go back
===> hahahaha, you know it.
5) Higher stress on the car, brakes, and my wallet
===> tell ben and chris that the price of slick is 2x actual price. let them stress out. you be fine.
u are an MD and i enable you as i am a drug dealer... erh.. drug rep...
===> you just need more wheels
3) 19" wheels require some small modifications and the clearance between the wheel and the rear LCA is uncomfortably small to me
===> small mod that takes a plier to do, i have 19" with plenty clearance. i fitted them no the car, not just based on calculations.
4) If I do run slicks, I won't go back
===> hahahaha, you know it.
5) Higher stress on the car, brakes, and my wallet
===> tell ben and chris that the price of slick is 2x actual price. let them stress out. you be fine.
u are an MD and i enable you as i am a drug dealer... erh.. drug rep...
11-10-2015, 06:54 AM
#1507
Rennlist Member
As previously discussed, Im with Joe & Manifold preferring 32 F and 34/35 R although Im ok as high as 33/36 but definitely they go off for me after 36.
Michelin actually recommend the below when the tire was launched...
Michelin actually recommend the below when the tire was launched...
11-10-2015, 07:13 AM
#1508
We just spent 3 days racing on the MPSC2 tyre and learnt that the sweet spot in the dry seems to be about 35 psi hot F and R. They were ok right up to 38 psi where they then suddenly "leave the building".
In the cold and wet, we struggled for grip until over 33 psi, and learnt the hard way we needed to pump them up another 4 psi to achieve this.
In the cold and wet, we struggled for grip until over 33 psi, and learnt the hard way we needed to pump them up another 4 psi to achieve this.
11-10-2015, 08:29 AM
#1510
Rennlist Member
On the RS the sweet spot was 30-33 all around.
To me drop off felt about to be 34 but this was on cool days about 10-15c.
Over 34 on warmer days overdriving the car they simply overheat and not psi will give grip.
I will say that they need some time to build heat and you can feel (and see on display) the temp and psi go down on cold days on long straights.
So pay attention the first couple laps at the end of the long straights.
To me drop off felt about to be 34 but this was on cool days about 10-15c.
Over 34 on warmer days overdriving the car they simply overheat and not psi will give grip.
I will say that they need some time to build heat and you can feel (and see on display) the temp and psi go down on cold days on long straights.
So pay attention the first couple laps at the end of the long straights.
11-10-2015, 08:39 AM
#1511
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Regarding tires losing grip during sessions, we need to remember that it's a function of both tire pressure and tire temp. Even if the pressure is optimal, grip can drop if the tire gets too hot. If driving hard, I find that my grip falls off after 10-20 minutes, regardless of tire pressure.
And of course another confounding factor is heat cycles. When my rear tires have apparently cycled out, they refuse to dig in and don't seem to care much what pressures I'm running.
And of course another confounding factor is heat cycles. When my rear tires have apparently cycled out, they refuse to dig in and don't seem to care much what pressures I'm running.
11-13-2015, 11:34 AM
#1513
Rennlist Member
11-13-2015, 06:11 PM
#1514
11-13-2015, 06:24 PM
#1515
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With decent tread, I haven't had any problem with the Cup 2 on wet roads. On the wet tracks, they're pretty good ... until they're not, at which point you can be glad stability control was on, if it was. If you decide to run wet tracks with stability control off, either have stellar car control skilz and good insurance, or hope your luck doesn't run out.