Blow-out at a track
#1
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Blow-out at a track
My today at Laguna Seca was ruined. I'll start from the beginning - it's a short story anyway.
I was late to the grid because of a bit of a delay with the sound suppressor installation (Laguna Seca limits sound to 90db, as compared to 95db limit for public roads in California - each 3dB is doubling the sound volume), so I ended up in the back of the grid. After the warm up lap, I start making my way to the front and get to a dark blue Corvette, that was going noticeably slower. It was just the first lap after warm up, so I did not attribute slow speed to lack of experience. Anyway, I follow him at a safe distance through corkscrew, planning to pass after Turn 10. As I power out from apex to start closing the gap, and all of the sudden he slams on brakes - he was probably running wide and got scared.
I made a split-second decision to lift and apply brakes while straightening the wheel to avoid spin-out (the car was loaded making of-camber left turn). I slowed down enough to avoid contact, but the maneuver made my car go wide and drop front outside wheel in dirt just before the track out curb started. The wheel then jumped on the curb and went pop. I had steering straight, so there was no spin, and I just pulled back on the track in 10 yards or so. I was a bit shocked because I hit the curb rather moderately - the suspension did not even bottom out.
So I pulled into the pits and saw that the tire was completely flat. So I ran less than one lap.
But here is the twist - it was a blessing in disguise. When I did a walk-around, I realized that the sound suppressor was scorching my rear bumper. The plate deflecting exhaust away from the car was a bit too small, so even one lap at 7/10 was enough to burn off a spot of paint. If I went for the entire session, the car could have caught on fire...
So the day was done.
I examined the wheel - looks completely fine, just a tiny rubber imprint where the wheel pinched the sidewall. The car seems fine too, other than the bumper issue.
I am very disappointed that 1) there was a car in open passing group that did such a dangerous thing (slamming brakes in the middle of acceleration out of a turn); 2) I was too eager to get to the clear track and left less safety space than I normally do; 3) most importantly, that the freaking tire burst like a balloon without much of an impact - if the tire had not burst, it would have been just a very minor two-wheels-off non-event.
I ran wide on other tires a number of times before, and more than once had a wheel jump on a leading edge of curbing, once I almost bit off my own tongue from the impact, and never had a tire burst. Track tire sidewalls are stiff enough to prevent pinched sidewalls in most cases. There was no force in the impact, no "boom" from suspension bottoming out, just a moderate jolt and pop. Either it was a very unlucky hit or the sidewalls of MPSC2 are not tough enough.
It's also another reason to think about running 19" wheels with taller profile tires. In fact, I had to borrow 19" fronts from 997.2 RS to get home (HUGE thanks to the owner!), and they worked really well - fit just fine, no codes, car drove fine. Not sure if rears would work just as well though.
I will now seriously think about getting a set of 19" wheels and probably using tires that I know can handle a moderate curb.
I was late to the grid because of a bit of a delay with the sound suppressor installation (Laguna Seca limits sound to 90db, as compared to 95db limit for public roads in California - each 3dB is doubling the sound volume), so I ended up in the back of the grid. After the warm up lap, I start making my way to the front and get to a dark blue Corvette, that was going noticeably slower. It was just the first lap after warm up, so I did not attribute slow speed to lack of experience. Anyway, I follow him at a safe distance through corkscrew, planning to pass after Turn 10. As I power out from apex to start closing the gap, and all of the sudden he slams on brakes - he was probably running wide and got scared.
I made a split-second decision to lift and apply brakes while straightening the wheel to avoid spin-out (the car was loaded making of-camber left turn). I slowed down enough to avoid contact, but the maneuver made my car go wide and drop front outside wheel in dirt just before the track out curb started. The wheel then jumped on the curb and went pop. I had steering straight, so there was no spin, and I just pulled back on the track in 10 yards or so. I was a bit shocked because I hit the curb rather moderately - the suspension did not even bottom out.
So I pulled into the pits and saw that the tire was completely flat. So I ran less than one lap.
But here is the twist - it was a blessing in disguise. When I did a walk-around, I realized that the sound suppressor was scorching my rear bumper. The plate deflecting exhaust away from the car was a bit too small, so even one lap at 7/10 was enough to burn off a spot of paint. If I went for the entire session, the car could have caught on fire...
So the day was done.
I examined the wheel - looks completely fine, just a tiny rubber imprint where the wheel pinched the sidewall. The car seems fine too, other than the bumper issue.
I am very disappointed that 1) there was a car in open passing group that did such a dangerous thing (slamming brakes in the middle of acceleration out of a turn); 2) I was too eager to get to the clear track and left less safety space than I normally do; 3) most importantly, that the freaking tire burst like a balloon without much of an impact - if the tire had not burst, it would have been just a very minor two-wheels-off non-event.
I ran wide on other tires a number of times before, and more than once had a wheel jump on a leading edge of curbing, once I almost bit off my own tongue from the impact, and never had a tire burst. Track tire sidewalls are stiff enough to prevent pinched sidewalls in most cases. There was no force in the impact, no "boom" from suspension bottoming out, just a moderate jolt and pop. Either it was a very unlucky hit or the sidewalls of MPSC2 are not tough enough.
It's also another reason to think about running 19" wheels with taller profile tires. In fact, I had to borrow 19" fronts from 997.2 RS to get home (HUGE thanks to the owner!), and they worked really well - fit just fine, no codes, car drove fine. Not sure if rears would work just as well though.
I will now seriously think about getting a set of 19" wheels and probably using tires that I know can handle a moderate curb.
Last edited by MaxLTV; 08-01-2014 at 11:56 PM.
#2
Glad to hear you're ok and the car is (relatively) fine, including not catching fire! Interesting feedback about the tires and that the 19s fit so well on the front. What rims and tires did you borrow (i.e. stock 997.2 RS rims, or aftermarket)?
Last edited by <3mph; 08-01-2014 at 11:15 PM. Reason: clarification
#3
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If 19's fit, the car must not have pccb's - pretty sure those fill the 20's completely.
#5
Yikes! Glad you are OK and the car didn't get ruined. So the 997 wheels fit? I thought they didn't. Good to know. As you said, a blessing in disguise you didn't stay out long enough for fire issues.
#6
Race Director
It's amazing, you single handedly answered one of the biggest gripes, and wrong predictions of a lot of guys on here.. So 19" DO fit with the stock rotors on the 991 gt3... Do you realize how many people you just made happy?
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#9
Why don't you think the rears will fit BTW? Maybe worth a try just in case...
EDIT: just saw your post above. Still worth a try maybe?
EDIT: just saw your post above. Still worth a try maybe?
Last edited by <3mph; 08-01-2014 at 11:47 PM. Reason: late
#11
Rennlist Member
^ that's what I recall
#13
Nordschleife Master
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!
#14
GT3 player par excellence
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max run 19" oem 997.2RS wheels
the rear has the RWS arm, i dont know if it will fit 19" or not. we can take a look next week. but my guess it that it wont.
max has steel brakes.
glad you made it back ok.
there were many ppl who shouldn't be in open group for sure.
the rear has the RWS arm, i dont know if it will fit 19" or not. we can take a look next week. but my guess it that it wont.
max has steel brakes.
glad you made it back ok.
there were many ppl who shouldn't be in open group for sure.
#15
Rennlist Member
Sorry to hear about the issues. What organizer was running this??