Porsche - Tire Explodes on the Fwy.
 

I decided to post this in O.T. as it is somewhat non-technical.

Anyway, the rear tire (driver side) on my SC Cab exploded. After my tire blow-out, the car zig-zagged all over the fwy -- scary *****:eek::eek:. Thankfully, it was at 5:00 a.m. and there was almost no traffic.

Upon arriving 4 hours late to work, I coincidently have 2 of my coworkers who knew of friends who died from tire blowout. Now paranoia on my part sets in.

1. Have you experienced a tire blow-out before?
2. For the statisticians, what is the chance of a rollover on a euro-spec-lowered Porsche?
3. On a cabriolet, death is guaranteed on a rollover, correct?:rolleyes:
4. I have 4 brand new tires; lately, I have been thinking about buying run-flats. Are they worth it?

1. Have you experienced a tire blow-out before?

yah, twice one front, one rear
both at 150km/h+
the rear ones are the worst

2. For the statisticians, what is the chance of a rollover on a euro-spec-lowered Porsche?

on tarmac, little chance
when you slide off, your guess is as good as mine
depends on what surface, angle, elevation, etc etc

3. On a cabriolet, death is guaranteed on a rollover, correct?:rolleyes:
nope
you might get launched out of it and walk away with nothing but a scratch
you could also end up fed from tubes talking like Stephen Hawkins or not even talking at all, just blink your eyes or something, or not at all


4. I have 4 brand new tires; lately, I have been thinking about buying run-flats. Are they worth it?[/QUOTE]

i don't have em, i like a little excitement now and then

I had a rear blowout in the Carrera at 90MPH. That was a bit freaky. Had to turn into it a few times to get the car stopped.

I've had a couple fail but only one "blow out". In both cases there was warning (a low-pitched groaning noise that gets higher or lower in response to vehicle speed / tire RPM). In both cases it was a failure of the tread-to-sidewall. One was in extremely hot temperatures, one was at night with cool temperatures. Both involved fairly long distances.

I suspect proper tire inflation pressure might have been a contributing factor (don't know that the pressure was wrong, but even if it was a little, it would have stressed the tread-to-sidewall point especially with many cycles of operation (think of how a severely underinflated tire will fail - lots of flex at that point). Possibly a contributing factor.

In both cases the tires were >3 years old too.

I had my car tires slashed a few weeks ago, I know the feeling.

Have someone look at them to determine the source of failure.

I didn't have a real blowout, but did have a catastrophic flat on the hwy. once. A truck had dropped a bunch of metal on the road and several cars behind me hit it too. My left rear tire went immediately flat at about 60 mph. It wasn't too scary until I got out to change the tire. If you've ever heard of the Springfield Mixing Bowl where 495/95/395 all merge, that's where it happened. I was on the road again in under 8 min. But that was a scary 8 min.

Out of curiousity, what brand of tires and what air pressure.

nope.
probably pretty low, but there are so many factors that could affect it, who knows.
no. I've seen/heard reports of plenty of conv rolling and the people being relatively unscathed.
I'd skip the runflats. Check your air pressure and tires more often. Most blow outs are due to running low pressure. Because the tires on the 911s are usually performance tires with short sidewalls, it's not as obvious when they are really low (short stiff sidewalls don't sound/feel flat the way a tire on a 70's full size chevy would)

Scary. Glad to hear you are okay.

Don't most runflats have worse handling characteristics than conventional tires?

I would think the extra-stiff sidewalls would be the cause. I'd personally rather have good handling tires--and hopefully be able to avoid accidents, than run-flats.

I can't fathom any sportscar flipping from a flat-induced skid on a flat road. As someone else mentioned, if you skid off the road all bets are off.

Go into a huge vacant parking lot in ANY car and try to make it flip. I don't think its possible. Trucks are a different story.

I have the SmartTire tire pressure monitoring system on my 911. $199 at TireRack. Great for peace of mind, alerts you if pressure/temp beyond user-selected limits, nice to look down and see LR tire 120F and 38 psi etc etc.

http://www.tirerack.com/accessories/categories/tpms.jsp

Got this after drove 2 hour in heavy rain at 50-70mph (stupid, won't do again) and then found out had 15psi in LR tire.

I lost a whole front wheel off of a VW rabbit when I was in college doing about 65-70 on a skinny rural road....... man that was a ride, but I kept it straight! The wheel narrowly missed a farm house. I was able to re-mount the wheel with a lug nut borrowed from each of the other three wheels and limped home.

Another vote for the SmartTire system.
Purchased mine after noticing that a rear tire (30 series) might be a tad low. Put the gauge on and it read 15 psi !!
A red light and warning buzzer go off when a pressure drops a predetermined amount from the normal psi (that you also input).

http://forums.pelicanparts.com/uploa...1195503312.jpg

max

We have runflats on the wife's BMW. I don't know what fool came up with that idea. I believe the reason BMW pushes tire/wheel insurance on buyers is because they fail more often than go-flat tires. We'll be putting go-flat tires on the car as soon as the current tires wear out, maybe sooner.

The blown tire was a BF Goodrich GForce model. I am somewhat definite that I hit something on the fway causing the blow-out on the rear and flat in the front.

With my new tires, I am having pulling to the left at acceleration. If you could provide your feedback, I would appreciate it. http://forums.pelicanparts.com/porsche-911-technical-forum/378134-marbles-my-915-tranny.html#post3597033

I will be contacting TireRack to determine if these are unidirectional.

Yep, not much fun - far worse when you have traffic on both sides - far worse on the rear of a 911.

If you stay on the road surface, minimal. Get sideways on the grass and all bets are off. Stay off the brakes - steer straight ahead get the car under control then start applying the brakes to slow - light brake pressure!

No guarantees in life, or death - But not something I would NOT like to experience either.

Nope - The run flats create their own issues. Monitor your tire pressures! They were not Kuhmo 712's were they - I have heard of a few instances where they have had catastrophic tire wall blow out. A few that have resulted in crashes on 911's. If not - give us the brand - please.

I had a tire blow out on an SUV at 80+ mph.

Stopped it on ther side of the highway, stuck the spare on, and drove away. nothing to get freaked about.

I think people who rolled Explorers after tire failures were all poor drivers. I wouldn't worry about a Porsche rolling over unless it's induced by the driver.

Had a bike tire blow out after hitting a pothole. Now THAT was interesting. Prolly not a true blowout as much as a rapid deflation, but oh baby did I ever have a laundry problem after that!

I imagine having one blow out on a motorcycle is pretty exciting as well.

I ride also. Did you land on your butt, and skidded on it....and after a few hundred yards, it flattened your butt ----- heh! heh heh!

Hey Flattbutt1, just kidding!