Goodyear tires and the 2005 Ford GT


dbk

The Favor Factory™
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Jul 30, 2005
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Xcentric

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Jul 9, 2012
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This forum is so cool.
 

Cobraguy

GT Owner
Yet another very clear and informative bit of info from Scott. Thanks Dave.
 

PL510*Jeff

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Nice write up Scott….good to learn a little more science about tire selection for the GT.
 

Brombear

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Thank you very much for that informative article.
 

Cobrar

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Scott review spoils us with a nice blend of the technical, albeit with a user-friendly style. How many iterations of the F1 tire did it take to make you guys happy?

Appreciate the comparative with the available Bridgestones that many are using on the GT. Good information!

Great work, as always Scott - thanks!
 

GTJack

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Yeah, buddy. This kind of information is part of why this Forum is the BEST! Great folks, and the designers/builders/testers all love the car and stay plugged into the user community.
 

Vince H

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Straight forward, no nonsense. Thanks Scott.

Vince H
 

THamonGT

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You said it all Scott, Thank You Very Much For A Very Informative article on a very important subject. Thanks Dave for posting this.
 

twobjshelbys

GT Owner
Jul 26, 2010
6,060
Las Vegas, NV
That is so cool! I know of no other "thing" that has explained design tradeoffs outside of the company. It is amazing that we are party to this.

So, now that this is out, it seemed like the Ford GT led the way with Goodyear tires. Was it this work that also led to the same tires (although in different sizes but otherwise sharing common design/compounds) to be used on the GT500?
 

GKW05GT

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May 28, 2011
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Yeah, buddy. This kind of information is part of why this Forum is the BEST! Great folks, and the designers/builders/testers all love the car and stay plugged into the user community.

+1 with Jack
 

jcthorne

GT Owner
Aug 30, 2011
792
Houston
Let me just chip in with my +1 as well. Thanks Scott and Dave. Love these articles.
 
A very informative and useful article. It actually gives reasons for selecting which tire you need based on your driving habits and GT use! First class!
 

jbyrnes

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Louisville CO
The higher horse increase for a SC engine vs a turbo'd motor as temps decrease is an interesting phenomenon. Why is this? Also then, shouldn't the GT be especially responsive to water injection?
 

Indy GT

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Jan 14, 2006
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Scott, Another fantastic technical article. Very, very good and as you can see from the comments, the technical content is appreciated by our owners. Glad you could capture all this information in one location for the owners to appreciate all the variables the Team considered as you came to consensus for the OE tire.:thumbsup

Scott review spoils us with a nice blend of the technical, albeit with a user-friendly style. How many iterations of the F1 tire did it take to make you guys happy?
Great work, as always Scott - thanks!

With a nod of appreciation to Mr. McGowan with whom I have had a number of discussions on this topic (and parenthetically was quite instrumental in the final Goodyear, Formula 1 tire construction for our FGT which is another story), I believe the FGT suspension Team engineers “went through the alphabet twice.” Decrypted, every tire submittal put forth by a tire manufacturer for OE evaluation is given a letter designator. Believe Goodyear went through about 52 different tire submittals to the FGT team to finally arrive at what characteristics the Team wanted out of the tire. Deduction- Goodyear really wanted to be the OE tire on this halo car and the FGT Team really pushed Goodyear to get just about every tire characteristic they wanted for our car. Win/win.:biggrin

The higher horse increase for a SC engine vs a turbo'd motor as temps decrease is an interesting phenomenon. Why is this? Also then, shouldn't the GT be especially responsive to water injection?
Air density. More dense charge at lower temperature. Perfect Gas Law. If you have an interest in aviation it is like density altitude and why planes take off in a shorter distance in cold weather. High, hot and humid increase takeoff distance because the wing is not as effective in creating lift nor does the normally aspirated engine make as much power. And SC engine makes power more quickly (directly with rpm) than a turbo setup (turbocharger lag due to exhaust mass flow). Thus more care is needed with an SC powered car with tires in "glass transition".

Sorry just cannot comment on the water injection. Why???
 
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jbyrnes

FORD GT OWNER
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Jun 13, 2006
224
Louisville CO
Indy,
(don’t want to derail the Tire thread here, but just to respond) I see why cooler air allows a denser charge for added HP, but unless the charge from the SC is cooler than the charge from a turbo’d motor the reaction to cooler air should be the same. Since water injection effectively adds HP by allowing either higher boost or ignition advance before detonation occurs it seems that adding it even to boosted-charge motors that already have an intercooler would be worth it for those trying to get every bit of available HP.
 

Kingman

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Aug 11, 2006
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Air density. More dense charge at lower temperature. Perfect Gas Law. If you have an interest in aviation it is like density altitude and why planes take off in a shorter distance in cold weather. High, hot and humid increase takeoff distance because the wing is not as effective in creating lift nor does the normally aspirated engine make as much power.

Real world example: PHX shuts down take-offs during high heat days (I think when it gets over 105/115 degrees) because they can't generate enough lift.
 

sahlman

Ford GT Team Alumni
Jul 21, 2011
329
Verona, WI
Hey All, glad the article was useful/informative and hopefully interesting. Thank you for the kudos.

Scott
 

sahlman

Ford GT Team Alumni
Jul 21, 2011
329
Verona, WI
The higher horse increase for a SC engine vs a turbo'd motor as temps decrease is an interesting phenomenon. Why is this? Also then, shouldn't the GT be especially responsive to water injection?

I will work to answer this coming weekend. I meant S/C versus naturally aspirated, but S/C's also tend to be more sensitive to ambient air temp than turbo charged engines as well. Will try to write a balance of practical and theory.

And yes, a few doing big mods to their engines have discussed water injection in their plans.

Scott
 

sahlman

Ford GT Team Alumni
Jul 21, 2011
329
Verona, WI
How many iterations of the F1 tire did it take to make you guys happy?

Yes, as Indy noted, we went deep into the alphabet a second time...at both ends of the car. That is a lot of tires.

Scott