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It should be measured cold. If it’s hot at 32 and 34, then it’s probably 27 and 28 respectively cold temp. 1 psi increase per 8-10 degree increase in temperature is normal for the tire. Measured hot is incorrect.
LOL.

You don't know me very well. I'll just leave it at that.

On the track, its all about hot pressure. You set the cold to get to where you need to be when the tires come up to temp/pressure.
 

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I can definitely vouch for the cup2r tires . My very fast amateur friend in a .2gt3rs went 2 seconds faster then motortrend .1gt3rs test at Laguna Seca. His optimal time was 3 second faster (Into P1 territory).

He was 3 seconds faster then his dunlop and cup2 tire time...

Problem for him is that they are $3,200 for a set and dropped off a cliff after 3 sessions... Me being the smart guy, I didn't line up in front of him until the end of day and he couldn't get around me and my 1:35 Lap time (he was doing 1:30-1:31 in first two sessions and became much slower by the end of day).

He's never spent the big money on those tires again after that day.
hey Unmac, what tire pressure are you running on the 3rs? I run them right about 30psi hot which seems good but the low tire pressure warning gets super annoying during the session
 

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I run them right about 30psi hot which seems good but the low tire pressure warning gets super annoying during the session
That's why I don't put TPMS sensors in my track wheels.

W/o sensors, you get one message when you fire up and then the light just stays on. No annoying alarms.
 

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Discussion Starter #26
Anyone running cup2 on the 720? I was looking at getting a set of those??
The short answer is this... People like to copy the regular track guys who are fast and economical with consumables... At the moment this is: Goodyear 3r tires, giro discs. (the not so regular guys keep the corsas and oem brakes
 

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Discussion Starter #27
hey Unmac, what tire pressure are you running on the 3rs? I run them right about 30psi hot which seems good but the low tire pressure warning gets super annoying during the session
I do 32 psi hot.

It increases about 2 psi per lap at Laguna Seca. Sometimes I don't stay out there long enough for them to even reach 32 psi and sometimes I'm having too much fun and I'm still out there and the pressures are at 38psi.

Someone reported on here that there was a software update or the newer year 720s/600 LT would stop chiming with the tire pressure warnings but still have the warning on the display (Mine is still the same with the chiming but I've learned to tune it out long ago). I also believe that Senna does not have the chiming with tire pressure warnings.
 

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I do 32 psi hot.

It increases about 2 psi per lap at Laguna Seca. Sometimes I don't stay out there long enough for them to even reach 32 psi and sometimes I'm having too much fun and I'm still out there and the pressures are at 38psi.
Friend of mine is a test engineer/driver for Goodyear who did a lot of the work on the SC3R. He says 32-35 hot is the sweet spot, though all of their testing was on Corvettes (C6 & C7).
 

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Discussion Starter #29
Friend of mine is a test engineer/driver for Goodyear who did a lot of the work on the SC3R. He says 32-35 hot is the sweet spot, though all of their testing was on Corvettes (C6 & C7).
Correct. 36 psi is the goodyear 3r street pressure (to support the weight of the ZL1 1LE.

I think people just have to test it for themselves to see. It's a little difficult to assess it by lap time because there is no way that you are going to get 6 to 8 unrestricted laps without traffic.

The recent track days are all sold out (people are itching to get out there), and the fast lap is going to be the second to third lap before you catch up to the back of the pack.
 

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I think people just have to test it for themselves to see. It's a little difficult to assess it by lap time because there is no way that you are going to get 6 to 8 unrestricted laps without traffic.
Unless you are a member at a track that is basically empty each morning during the week. :) That's how I can do legit tire testing for the magazine (GRM).

Of course, it's closed for repaving at the moment, which is killing me.
 

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Discussion Starter #32
I went to the Goodyear website and entered my vehicle and it said the tire did not fit. What am I missing?
Let's just say that AWH stirred the pot when he said 245 mm was now available in the goodyear 3r's. All of the 720s guys were using 235 mm with the 3R's. No one has used the 245 mm fronts because they haven't been available.

I entered 2018 720s on tirerack and they show up (the fronts 245 mm show as being back ordered).

Goodyear website shows 720s but when selecting it the tires show up as not available and go to local goodyear tire shop. If you do it by tire size instead of vehicle then it shows that it is not available to order on-line.

I needed new 3r tires. After Andy posting, I contacted the guys who I order from. Next two postings are the text message.
 
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