Wwabbit
GT Owner
Are you looking for a nudge? None of this stuff makes sense. And we are all working on other things. Delete away. :wink
Do original oem tires become unsafe after a number of years?
- Thread starter Willrx
- Start date
Are you looking for a nudge? None of this stuff makes sense. And we are all working on other things. Delete away. :wink
OEM Valve Stems
I checked with my local Ford dealer and asked my parts guy if he could get me new oem valve stems since I was changing my tires this week to the Bridgestones. He said there was 400 available for the standard 6 spoke wheels and 200 available for the optional BBS 10 spoke wheels. My question to him was when were these stems manufactured? If rubber tires have a shelf life then do the rubber components built into these rubber and metal stems have a shelf life too? He did not know if the stems were manufactured in the 2005-2006 range or anywhere in between. So do I buy the oem valve stems that were made for my wheels or do I use a generic metal stem from Discount Tire? Anybody have any thoughts on this matter?
I checked with my local Ford dealer and asked my parts guy if he could get me new oem valve stems since I was changing my tires this week to the Bridgestones. He said there was 400 available for the standard 6 spoke wheels and 200 available for the optional BBS 10 spoke wheels. My question to him was when were these stems manufactured? If rubber tires have a shelf life then do the rubber components built into these rubber and metal stems have a shelf life too? He did not know if the stems were manufactured in the 2005-2006 range or anywhere in between. So do I buy the oem valve stems that were made for my wheels or do I use a generic metal stem from Discount Tire? Anybody have any thoughts on this matter?
I've gone through 5 or 6 sets of tires on my original wheels, and never had an OEM valve stem leak over 7 years. Still on the wheels and performing perfectly. Jeff may concur....
I'm afraid some bozo would mark up the wheels installing new ones.
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Wwabbit
GT Owner
When it comes to rubber or latex items, new is better than NOS. Go with new production that meets OEM specs.
Wwabbit
GT Owner
For any particular tire where the Porsche approval (N) applies (tires used on a Porsche), you might want the latest series available for that particular tire, N0, N1.....N3, etc. That is if you even care about what Porsche thinks. Otherwise, get what you want with the latest mfgr date available.
RPM217
2005 white/blue stripe
Why 30 psi RPM217?
Reason I ask is I have Bridgestones with 8,000 miles on them and two track days. Granted the rears are about done but the fronts show very little wear on the overall tread depth and corners. I've gone with 32 psi front and rear.
The difference may be our non-summer air and street temps??
Xcentric
GT Owner
^^^On the rears, what is the tread depth on the edges compared to the center?
At 32, my first set of Eagle rears was down to 2/32 at the center and 5/32 at the edges. I don't think these wide tires will ever wear evenly across, but at 28 (for street only) on my second set, they are wearing better.
At 32, my first set of Eagle rears was down to 2/32 at the center and 5/32 at the edges. I don't think these wide tires will ever wear evenly across, but at 28 (for street only) on my second set, they are wearing better.
Indy GT
Yea, I got one...too
High Speed Tire Certification
Willrx-
Tire age is certainly an important consideration on our car and this thread is very interesting regarding our tire options going forward now that Goodyear has effectively priced themselves out of the market. In the 2008 – 2010 timeframe many of us owners wanted to purchase new OE Goodyears but the only tires remaining for purchase were left over from the 2004 - 2006 production run. With the limited application of our tire sizes, Goodyear did not seem very motivated to produce newer mold date tires. Many owners opined the available stock tires (if they could find any) were getting quite “old” to be qualified as new tires with the 200+ mph characteristics we wanted (and Ford Certified) on our car. Many owners raised Goodyears awareness of producing another batch of F1 tires for the GT which they reluctantly did, but increased the per unit cost 100% so at least they could say the tires were still available, just at a ridiculous price. Enter the Bridgestones.
Not to hijack your thread, but I would like to interject some thoughts on the tire testing Ford did for our vehicle on which some have commented.
To be sure, Ford did a tremendous amount of high speed verification testing on our car. I believe much of this investigative research was conducted on static or moving plane wind tunnels, not necessarily on the track. Although there was high-speed track validation signoff testing done at Nardo, Italy. See below. And I am also sure Ford required of Goodyear to do extensive, let me repeat that, EXTENSIVE 200+ mph testing on their production supplied Formula F1 tires. Liability concerns alone for Ford dictated this safety issue had to be inspected from every possible failure scenario. Remember the Firestone Wilderness tire separation fiasco. This could not be repeated, especially on a halo vehicle.
Our Ford GT “Team History” book indicates Ford took two FGT vehicles over to Nardo, Italy in May 2004 for a week long test “to complete all the high speed sign-off requirements for handling, as well as powertrain, cooling and assorted other systems”. This is where Mr. McGowan clocked the Vmax speed of 211.89 mph. Understand that at Wide Open Throttle (WOT) our vehicle consumes a full load of 17.5 gallons of fuel in about 15 minutes, so this high speed testing was frequently punctuated by either running out of fuel (as one of Mark’s video’s shows) or frequent stops to refuel. Further, the history book states that, “By the time we were done, we had completed more than 500 miles of testing at over 200 mph with no real issues.”
Based on the 500 mile statement that would mean about 2.5 hours (total) of 200+ mph car testing was achieved, at least at Nardo. So it was not really a whole lot of hours of actual production vehicle testing, but I believe a significant amount of component and model testing. Perhaps Mark (or other Team member) can chime in and let us know if any further 200+ mph track testing was done on our car.
Willrx-
Tire age is certainly an important consideration on our car and this thread is very interesting regarding our tire options going forward now that Goodyear has effectively priced themselves out of the market. In the 2008 – 2010 timeframe many of us owners wanted to purchase new OE Goodyears but the only tires remaining for purchase were left over from the 2004 - 2006 production run. With the limited application of our tire sizes, Goodyear did not seem very motivated to produce newer mold date tires. Many owners opined the available stock tires (if they could find any) were getting quite “old” to be qualified as new tires with the 200+ mph characteristics we wanted (and Ford Certified) on our car. Many owners raised Goodyears awareness of producing another batch of F1 tires for the GT which they reluctantly did, but increased the per unit cost 100% so at least they could say the tires were still available, just at a ridiculous price. Enter the Bridgestones.
Not to hijack your thread, but I would like to interject some thoughts on the tire testing Ford did for our vehicle on which some have commented.
To be sure, Ford did a tremendous amount of high speed verification testing on our car. I believe much of this investigative research was conducted on static or moving plane wind tunnels, not necessarily on the track. Although there was high-speed track validation signoff testing done at Nardo, Italy. See below. And I am also sure Ford required of Goodyear to do extensive, let me repeat that, EXTENSIVE 200+ mph testing on their production supplied Formula F1 tires. Liability concerns alone for Ford dictated this safety issue had to be inspected from every possible failure scenario. Remember the Firestone Wilderness tire separation fiasco. This could not be repeated, especially on a halo vehicle.
Our Ford GT “Team History” book indicates Ford took two FGT vehicles over to Nardo, Italy in May 2004 for a week long test “to complete all the high speed sign-off requirements for handling, as well as powertrain, cooling and assorted other systems”. This is where Mr. McGowan clocked the Vmax speed of 211.89 mph. Understand that at Wide Open Throttle (WOT) our vehicle consumes a full load of 17.5 gallons of fuel in about 15 minutes, so this high speed testing was frequently punctuated by either running out of fuel (as one of Mark’s video’s shows) or frequent stops to refuel. Further, the history book states that, “By the time we were done, we had completed more than 500 miles of testing at over 200 mph with no real issues.”
Based on the 500 mile statement that would mean about 2.5 hours (total) of 200+ mph car testing was achieved, at least at Nardo. So it was not really a whole lot of hours of actual production vehicle testing, but I believe a significant amount of component and model testing. Perhaps Mark (or other Team member) can chime in and let us know if any further 200+ mph track testing was done on our car.
Xcentric
GT Owner
Good points. A few things about the testing are unclear. How was the 500+ miles split between the two cars? How many sets of tires were used?
Indy GT
Yea, I got one...too
Very good questions!
I doubt the tires were changed on either of the cars as I would not expect much tire wear from just gong around the track at high speed. But I only guess.
The Nardo group photo shows that in addition to Mr. McGowan, other Forum contributors Denis Breitenbach and Alex Szilagyi were part of the sign-off Team. Perhaps one of them remembers or could comment.
I doubt the tires were changed on either of the cars as I would not expect much tire wear from just gong around the track at high speed. But I only guess.
The Nardo group photo shows that in addition to Mr. McGowan, other Forum contributors Denis Breitenbach and Alex Szilagyi were part of the sign-off Team. Perhaps one of them remembers or could comment.
sahlman
Ford GT Team Alumni
For sure one of the 3 Ford support personnel in Indy’s post will have to answer how many laps per car and per tire set. I don’t recall exactly but it was only a few sets of tires…I think 1 set per car.
I have a few notes on high speed runs on the GT and corresponding testing. Always inflate tires to 40 psi front and rear cold if running above 150 mph as the doorjamb sticker notes! :wink
Nardo was heavily biased toward sign off on high speed stability at Vmax (top speed maneuverability, braking stability,etc). Yes final sign off on tire durability too, but the almost 8 mile circle at Nardo has less than 10 deg of banking so it is pretty low loading (vertical and lateral) compared to all of the 200 mph runs back on our 5 mile ovals with 1mile straights and 30 deg of banking in the top lane. Nardo is so much easier on tires and I believe they looked like new after those runs. It was a none-event from a tire standpoint.
Jeff Walsh ran the first 200 mph runs at the Michigan Proving Grounds (MPG) 5 mile oval in Romeo, MI in CP4. Others including McGowan made runs at MPG. Some of the hardest high speed development for tires was done by McGowan at the identical 5 mile oval at APG in Yucca. We had to push Goodyear a lot to hit all of our targets along with the high speed durability. Easy to hit one or two of our targets, but hitting them all (handling, ride, steering feel, high speed capability, etc) was a challenge. An awful lot of 200 mph runs were made, but I do not know the exact count or mileage. I only got to run 180-190 mph continuous since my run was not preplanned and didn’t have ambulance and safety gear. Still a blast. The sound of expansion cracks at tenths of a second blasting through the corner 180+ is pretty awesome. Corner entry is the only slightly challenging part, but still fairly straight forward because the car is so stable.
And yes, our high speed durability requirements were more difficult than ever because Ford would not budge on some updated and very difficult requirements due to the Firestone Debacle (and hence Bridgsetones were not an option on the car). The separate lab testing by Goodyear on their high speed drums for high speed durability of the tires was significant and constant and part of Ford's normal testing requirements....except much harder than a year earlier.
High speed stability and aero work was also ongoing in which full scale non-moving ground plane tunnels and 40% scale moving ground plane tunnels were used for a great base. All of the high speed runs including large straight away/runway work helped confirm the cars stability.
The FGT had to be truly capable of running at 200 mph continuous (cornering on the big ovals) and not just achieve the number. She is a stable machine and we all worked hard to make it that way.
Scott
I have a few notes on high speed runs on the GT and corresponding testing. Always inflate tires to 40 psi front and rear cold if running above 150 mph as the doorjamb sticker notes! :wink
Nardo was heavily biased toward sign off on high speed stability at Vmax (top speed maneuverability, braking stability,etc). Yes final sign off on tire durability too, but the almost 8 mile circle at Nardo has less than 10 deg of banking so it is pretty low loading (vertical and lateral) compared to all of the 200 mph runs back on our 5 mile ovals with 1mile straights and 30 deg of banking in the top lane. Nardo is so much easier on tires and I believe they looked like new after those runs. It was a none-event from a tire standpoint.
Jeff Walsh ran the first 200 mph runs at the Michigan Proving Grounds (MPG) 5 mile oval in Romeo, MI in CP4. Others including McGowan made runs at MPG. Some of the hardest high speed development for tires was done by McGowan at the identical 5 mile oval at APG in Yucca. We had to push Goodyear a lot to hit all of our targets along with the high speed durability. Easy to hit one or two of our targets, but hitting them all (handling, ride, steering feel, high speed capability, etc) was a challenge. An awful lot of 200 mph runs were made, but I do not know the exact count or mileage. I only got to run 180-190 mph continuous since my run was not preplanned and didn’t have ambulance and safety gear. Still a blast. The sound of expansion cracks at tenths of a second blasting through the corner 180+ is pretty awesome. Corner entry is the only slightly challenging part, but still fairly straight forward because the car is so stable.
And yes, our high speed durability requirements were more difficult than ever because Ford would not budge on some updated and very difficult requirements due to the Firestone Debacle (and hence Bridgsetones were not an option on the car). The separate lab testing by Goodyear on their high speed drums for high speed durability of the tires was significant and constant and part of Ford's normal testing requirements....except much harder than a year earlier.
High speed stability and aero work was also ongoing in which full scale non-moving ground plane tunnels and 40% scale moving ground plane tunnels were used for a great base. All of the high speed runs including large straight away/runway work helped confirm the cars stability.
The FGT had to be truly capable of running at 200 mph continuous (cornering on the big ovals) and not just achieve the number. She is a stable machine and we all worked hard to make it that way.
Scott
Indy GT
Yea, I got one...too
This is what makes this Forum so special.
Sharing input from the actual engineers on the FGT program to us owners.
Thanks very much Scott for sharing your thoughts on this testing aspect!
Sharing input from the actual engineers on the FGT program to us owners.
Thanks very much Scott for sharing your thoughts on this testing aspect!
andymlow
GT Owner
Can anybody compare and contrast the recommended Bridgestones with the new Michelin Super Sports??
sahlman
Ford GT Team Alumni
Sinovac
GT Owner
What size front tires are you using? The 255 or 265, and is your car lowered? The stance of your car is very nice