Tires Blowing Out?!

agreed I would suspect tire pressure issues, on a run like they did they should check pressures very often

 

It's interesting to note that on TRs F owned up to the need to run higher tire pressures at sustained high speed and spec'd that directly in the OM. Has this conveniently "faded away" for the newer F models?

 

After looking at Brian's pictures in the main forum, you can tell that there were drives through the mountains and some snowy areas as well. Elevation changes and weather changes drastically change the pressures of the tires. Having something too low, will put extra force on the sidewalls. Those sidewalls can be strong, but can be a weak link if they are being driven on. There's many factors here, especially because with cars that have a lot of downforce, you are putting pressure on the tires as well. Best thing to do - check pressures in changing conditions with every fill up for the Players Run/Gumball type of events.

 

I also think that the importance of tires is highly underestimated by many drivers.

I read tests about tires on a regular basis. Naturally a review in a "normal" car magazine will apply other criteria than a test in a magazine dedicated to sports cars. This is why I normally rely on the tests in "Sport Auto".

As to the ranking of brands: With the rapid development of ever new tires the ranking changes from year to year. And the ranking is also slightly affected by tire size. This is why I always try to get the latest reviews whenever I am about to buy new tires.

As a general figure one can say that the top positions are normally held by

- Continental,
- Pirelli,
- Michelin and
- Dunlop.

Other renowned brands like Bridgestone or Goodyear normally fall apart. But sometimes there are excellent tires from other brands, too, e.g. last winter I bought snow tires from Goodyear for our family van as they had an excellent evaluation in a car magazine.

"Good" or "bad" is also depending on your demand profile. I personally prefer predictability of a tire over sheer performance. And stopping distances on wet roads are more important to me than those on dry roads. There ALWAYS is a trade-off.

At a good dealership they should have the latest reviews from US car magazines available. Then YOU decide which tire is best

 

Randam mutterings and IMHO's.....I believe in Porsche's quality control and rigorous testing of its road cars is unparalleled. Its OEM tires are Pirelli. I have recently, however, had a big bulge develop in a Pirelli Asimmetrico N3 (OEM on Porsche Turbo). Before blowout (which never occurred), I detected a vibration. I have also handled, as a lawyer, a few tire blowout cases from a product liability perspective, and don't think it is very common to have an instantaneous failure/blowout unless you encouter road debris. That is probably your most serious threat, and any tire hitting a piece of debris at 150+ can fail. But get real, how many miles are you going to be driving at 150 and are you going to be doing it blindly? I wouldn't suggest it at night, or if your car has the slightest vibration. Also, get your tires Road Force balanced, the best method, which tests for vibration at speed with force applied to the tire. Then get them rechecked every 2500 miles or so (about 25% of tire life) as the tire will change with normal wear.

 

Goodyear is #1 in Racing...........



HTH

 

Are you sure that's not the MAXIMUM rated pressure. That's not necessarily what it needs to be set at.

 

I participated in the players run.
My fiancee was driving when we had a blow out at 110. (passenger rear)
Nothing happened to the car and the trie actually protected the rim pretty perfectly.
My tires were checked prior to doing the run and there was a lot of tred remaining.
Because of the long long high speed driving that we did, and the tires being slightly over inflated for the conditions, the center of the rear tires were wearing out quicker.
we hit 160-170 every day.
We thought we could make it back to LA before changing tires but 60 miles outside of Vegas the tire blew. It looks like we hit a little nail/plastic in the center and that started the tearing and shreading of the tire.
I was running Bridgestone S01 ZR.
The only tire that we could find was a BF Goodrich ZR about 87 miles a way.
So thats what I ahve now- do not know if I will keep them or not.

 

The pressure on the side wall IS the max. pressure, this is why the figure has a "max." written in front of it.

But I also like to overinflate the tires a little, I have the impression that this provides a slightly improved handling.

 

I had a vette with Goodyear Eagles. I had this experience around 1998. One time on a straight road (BW Prkwy) going no faster then 75 the rear left tire blew out and actually caused a hole in the wheel well. The car handled ok and I was able to get to the side of the road. After changing the tires, (2 rear) and months later I was on the 495 Beltway and the passenger side rear tire tread seperated from the sidewall. I actually saw the tire rolling behind me until I slowed and watched it pass me then hit the median. What a sight... the cars behind me slowed, I had about 100 yds clear in my rear view mirror with the cars stopping. If you know the Beltway, you know this isn't normal. I only felt a slight yaw when it happened. The car handled ok and I was able to drive her to the shoulder. I wasn't going over 70mph with the traffic. So, I switched to Michelins and never had another problem. They are also on my other cars.

I really appreciate your stories. I think we need to find out the best tires for our vehicles. We trust a lot to our tires. I'm still trying to decide what to put on the 355.

 

The recommendations from Goodyear booklet may apply to most cars but I can tell you the numbers are off in case of Modenas. Owners manual recommends tire pressure to be checked cold or less than 2 miles of driving (let's say you want to get it to a gas station). I check my tires every time I am driving out of the garage and check them again when I come back. I have noticed when hot the pressure could be at least 8 PSI higher than cold. I have also investigated and found since Modenas come OEM with Pilot Sports, P0s, or S02-As OEM, Ferrari recommends totally different tire pressures at cold for each tire manufacturer. The other important factor is the Max loading on the tires at a specified max pressure. You probably won't exceed that in an F-car but it is something to be aware of.

I have gone through a set of Pilot Sports and now a set of P0s on my car. Overall, I would say P0s have a stronger sidewall and the grip is fantastic after a few minutes of warming them up, but treadwear is somewhat less desirable. Corss my fingers, I do over 150/160 regularly and tires have held up very well. I am getting new tires and opted to get P0s again.

 

Players is a non-speed event I thought but if they are doing 100+ on public roads it is both dumb and risky to life and limb. You see racers solve the tire pressure problem by doing testing on the road circuit in question and setting empirical tire pressures then altering them by tire pyrometer readings at several points over the tread on each tire. Checking your pressures is for street driving and is designed to be a factory compromise based on testing done for a specific tire and speciic weight etc of car to meet the average condition. The average condition is not 150mph. Race tires are a special compund designed for the higher speeds. Street tires while they say can do 150+ the testing for these is under strict lab conditions and not under the conditions of real street use at 150mph. On the street you have variable road conditions that pop up infront of you like pot holes, scrape the tire sidewalls on curbs, hit ladders on the freeway etc. Engineering a tire to survive These highly variable issues make make designing a race tire seem easy. So if guys in the Plyaers are blowing out street tires at 100mph I'm not surprized. You have a bunch of guys that really have never done any testing and probably none have a tire pyrometer and no-one has driven the circuit to test the road conditions inwhich the tires will heat or know the ambiant temperature that will effect the tire pressures etc. etc... So IMO street tries are street tires and race tires are race tires and each have a respective place. You can treat a street tire like a race tire and it will work well up to its adhesion limits but you have to adheare to the same testing and runn that racers do with race tires and use the tire pyrometer. Most real racers also believe in the probe pyrometer over the IR ones just incase you guys want to run out and by some guages. The botom line is the factory street recommendation is absoultely perfect for USA roads at 0-65mph.

YMMV