Blow-out at a track
08-02-2014, 03:59 AM
#16
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Max. Glad to hear all is ok. Could have been much worse with that exhaust thing burning your rear bumper.
Did you go out with low tire pressures? If this was your first proper lap of the day and you had let the tires down to 20 psi to accommodate hot pressures this may have helped cause the issue. I say that only because I tried similar once on my first session and a more experienced racer buddy saw me do it and told me that it was not advisable and to only run small psi out of them for first lap and let them overheat a bit and then lower them substantially for second session as the damage to sidewall running them too low and the potential issues of a cold under inflated tire on the track outweighed having them too hot for half a session. Just a thought here thats all...
P.S. My tech is pretty certain 19" will work fine front and rear and doesnt believe RWS arm will be a problem for the rear at all....
Did you go out with low tire pressures? If this was your first proper lap of the day and you had let the tires down to 20 psi to accommodate hot pressures this may have helped cause the issue. I say that only because I tried similar once on my first session and a more experienced racer buddy saw me do it and told me that it was not advisable and to only run small psi out of them for first lap and let them overheat a bit and then lower them substantially for second session as the damage to sidewall running them too low and the potential issues of a cold under inflated tire on the track outweighed having them too hot for half a session. Just a thought here thats all...
P.S. My tech is pretty certain 19" will work fine front and rear and doesnt believe RWS arm will be a problem for the rear at all....
08-02-2014, 10:36 AM
#17
Nordschleife Master
08-02-2014, 11:12 AM
#18
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Cannot confirm experience with MPSC2 but Macca may have a point reg. cold tire pressure! Never hit the curbs with cold low PSI tires!!
Did 3 track days (sort of open pit lane style) and I am doing tons of kerbs and never hat an issue (so far). Was in Spa and Hockenheim and you ahve to do lots of kerbs to be quick. Especially one left hand kink in Hockenheim after the "Sachskurve" is pretty nasty. Also Spa the bus stop chicane but there the speed is quite low .... just saying
P
Did 3 track days (sort of open pit lane style) and I am doing tons of kerbs and never hat an issue (so far). Was in Spa and Hockenheim and you ahve to do lots of kerbs to be quick. Especially one left hand kink in Hockenheim after the "Sachskurve" is pretty nasty. Also Spa the bus stop chicane but there the speed is quite low .... just saying
P
08-02-2014, 11:43 AM
#19
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To the OP that sucks but I'm not sure you can judge the tire sidewalls weak or the blowout due entirely to the decreased sidewall relative to other cars. These cars are said to really do well at soaking up big hits. . . but that doesn't mean that those big hits are. . . .big.
Anyway, not sure if that makes any sense. But I'm with you about the desirabililty of tracking with 19's.
Forgeline is already building 19's. Only issue that it'll mess with your gearing a bit b/c the OD of currently available track 19's don't replicate the OD of OEM 20's. I haven't looked at 19" tire selections but R6s are an option but I'd prefer a 19" tire that can be street driven to the track.
Anyway, not sure if that makes any sense. But I'm with you about the desirabililty of tracking with 19's.
Forgeline is already building 19's. Only issue that it'll mess with your gearing a bit b/c the OD of currently available track 19's don't replicate the OD of OEM 20's. I haven't looked at 19" tire selections but R6s are an option but I'd prefer a 19" tire that can be street driven to the track.
08-02-2014, 01:29 PM
#20
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It was a bad day for a bunch of people. Unusual amount of carnage on track today. :-(
I always worry a bit about 'sold out' events. It usually means that people are shoehorning themselves into inappropriate run groups so they can still get a track day.
Glad you and the car are still ok. Hope to see you out there again soon, my friend!
I always worry a bit about 'sold out' events. It usually means that people are shoehorning themselves into inappropriate run groups so they can still get a track day.
Glad you and the car are still ok. Hope to see you out there again soon, my friend!
The tire was at 30psi (per dash meter) by the time this happened, low psi is not a factor here.
Just to clarify, I did not hit the curb the way it's meant to be hit. The wheel was going in the dirt parallel to the edge of track and jumped on the curb from dirt. Attacking curbs normally never caused any issues. Still, I had much stronger impacts in other cars/tires, without sidewall damage. I think taller sidewall might have helped or sidewall like in AD08R - they are pretty much run-flats.
I'm experimenting with the sound suppression already, so I'll let someone else to figure out 19" wheels and tires and copy then.
Losing a track day feels like getting a bloody nose without returning a punch - now want to pick up another fight ASAP.
08-02-2014, 02:18 PM
#22
GT3 player par excellence
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08-02-2014, 03:03 PM
#23
Nordschleife Master
08-02-2014, 08:55 PM
#24
Burning Brakes
That completely sucks. I also can agree that track days are such a complete **** show.
I must say, just because the "warm up lap" is over doesn't mean GAME ON as in the green flag is waving. Guys and tires warm up times differ. I use extra caution for the first five laps and let anyone up my *** for the first few laps pass immediately. I catch them later anyway.
Good luck with the tire. Elite track days would be awesome.
I must say, just because the "warm up lap" is over doesn't mean GAME ON as in the green flag is waving. Guys and tires warm up times differ. I use extra caution for the first five laps and let anyone up my *** for the first few laps pass immediately. I catch them later anyway.
Good luck with the tire. Elite track days would be awesome.
08-02-2014, 11:36 PM
#25
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i saw MAX's blown tire. its right on the sidewall. i am surprised to. the bead didn't come off, the wheel was not bent.... could it be sidewall is too soft? but how, the sidwall was short, should not be soft....
i would like to know more on that issue.
and at least for the very near future, 991 GT guys should have spare tires either in trailer or at home b/c i doubt these are rubbers you can find quickly, even from dealers.
08-02-2014, 11:59 PM
#27
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That completely sucks. I also can agree that track days are such a complete **** show.
I must say, just because the "warm up lap" is over doesn't mean GAME ON as in the green flag is waving. Guys and tires warm up times differ. I use extra caution for the first five laps and let anyone up my *** for the first few laps pass immediately. I catch them later anyway.
Good luck with the tire. Elite track days would be awesome.
I must say, just because the "warm up lap" is over doesn't mean GAME ON as in the green flag is waving. Guys and tires warm up times differ. I use extra caution for the first five laps and let anyone up my *** for the first few laps pass immediately. I catch them later anyway.
Good luck with the tire. Elite track days would be awesome.
08-03-2014, 12:13 AM
#30
Nordschleife Master
yah, u can scare Wa, hahahah.
i saw MAX's blown tire. its right on the sidewall. i am surprised to. the bead didn't come off, the wheel was not bent.... could it be sidewall is too soft? but how, the sidwall was short, should not be soft....
i would like to know more on that issue.
and at least for the very near future, 991 GT guys should have spare tires either in trailer or at home b/c i doubt these are rubbers you can find quickly, even from dealers.
i saw MAX's blown tire. its right on the sidewall. i am surprised to. the bead didn't come off, the wheel was not bent.... could it be sidewall is too soft? but how, the sidwall was short, should not be soft....
i would like to know more on that issue.
and at least for the very near future, 991 GT guys should have spare tires either in trailer or at home b/c i doubt these are rubbers you can find quickly, even from dealers.
Just had a thought: Maybe this 'velvet' lettering technology on the mpsc2 sidewalls is to blame?
http://www.complex.com/sports/2013/0...s-black-series
