Toyo R 2nd day fail
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Joined: Dec 2016
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Toyo R 2nd day fail
I posted a 2:16 Sebring lap time on the 295/30/19 & 354/30/19 Toyo R. That lap was set on the tires 5th heat cycle.
Well, they went downhill fast from there.
2nd day out tires were terrible, best I could muster was a 2:19
So the search for a more affordable and longer lasting tire that the car is happy with, continues:
Well, they went downhill fast from there.
2nd day out tires were terrible, best I could muster was a 2:19
So the search for a more affordable and longer lasting tire that the car is happy with, continues:
Burning Brakes
Joined: Jan 2011
Posts: 972
Likes: 242
From: San Jose CA
Yeah, the PS4S is an amazingly grippy tire (more like a 200TW rated tire grip wise) and is perfect for the street when it is 60 degrees out, but I can get them out of their optimal zone even on the street on a 70+ degree day.
Sr.Random input generator
Joined: Jan 2008
Posts: 7,779
Likes: 2,211
From: Sammamish, WA
I was also underwhelmed with my Toyo R tires when I tried them. It was just never fast enough for me (I was expecting them to be significantly faster than RRs, and they did not feel so), but surpised that they are likelyheat cycled out in your case. Toyo tires are famouse for their consistency.
There was a podcast where they mentioned first batch of Toyo R tires were not good, and Phil's tire returned them (and Toyo replaced them). I wonder if you've run into a set like that (but I know, the otdds are you didn't since it was during the early times of when this tire was introduced).
There was a podcast where they mentioned first batch of Toyo R tires were not good, and Phil's tire returned them (and Toyo replaced them). I wonder if you've run into a set like that (but I know, the otdds are you didn't since it was during the early times of when this tire was introduced).
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Joined: Dec 2016
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I was also underwhelmed with my Toyo R tires when I tried them. It was just never fast enough for me (I was expecting them to be significantly faster than RRs, and they did not feel so), but surpised that they are likelyheat cycled out in your case. Toyo tires are famouse for their consistency.
There was a podcast where they mentioned first batch of Toyo R tires were not good, and Phil's tire returned them (and Toyo replaced them). I wonder if you've run into a set like that (but I know, the otdds are you didn't since it was during the early times of when this tire was introduced).
There was a podcast where they mentioned first batch of Toyo R tires were not good, and Phil's tire returned them (and Toyo replaced them). I wonder if you've run into a set like that (but I know, the otdds are you didn't since it was during the early times of when this tire was introduced).
Hmmm… didn’t know about this.
I already disposed of them so I guess we will never know.
Heel & Toe
Joined: Jul 2025
Posts: 15
Likes: 16
Had a code brown experience with my Toyo R's. To be fair, that was on me as it I just didn't give the tires enough time to warm up.
Started with fairly high hot pressures (36 - 37), dropped them during the day and they seemed to work better around 32 - 33. Turned a PB, although I was driving pretty conservative after my morning mishap. I will drop the pressures to ~30 next time I'm out on them to see how they work.
Started with fairly high hot pressures (36 - 37), dropped them during the day and they seemed to work better around 32 - 33. Turned a PB, although I was driving pretty conservative after my morning mishap. I will drop the pressures to ~30 next time I'm out on them to see how they work.
Thread Starter
Pro
Joined: Dec 2016
Posts: 601
Likes: 134
Had a code brown experience with my Toyo R's. To be fair, that was on me as it I just didn't give the tires enough time to warm up.
Started with fairly high hot pressures (36 - 37), dropped them during the day and they seemed to work better around 32 - 33. Turned a PB, although I was driving pretty conservative after my morning mishap. I will drop the pressures to ~30 next time I'm out on them to see how they work.
https://www.youtube.com/watch?v=O5vY9G0lWi4
Started with fairly high hot pressures (36 - 37), dropped them during the day and they seemed to work better around 32 - 33. Turned a PB, although I was driving pretty conservative after my morning mishap. I will drop the pressures to ~30 next time I'm out on them to see how they work.
https://www.youtube.com/watch?v=O5vY9G0lWi4
Le Mans Master
Joined: Jul 1999
Posts: 5,007
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From: Cincinnati Ohio
Burning Brakes
Joined: May 2025
Posts: 788
Likes: 598
From: Bucks County, PA
Had a code brown experience with my Toyo R's. To be fair, that was on me as it I just didn't give the tires enough time to warm up.
Started with fairly high hot pressures (36 - 37), dropped them during the day and they seemed to work better around 32 - 33. Turned a PB, although I was driving pretty conservative after my morning mishap. I will drop the pressures to ~30 next time I'm out on them to see how they work.
https://www.youtube.com/watch?v=O5vY9G0lWi4
Started with fairly high hot pressures (36 - 37), dropped them during the day and they seemed to work better around 32 - 33. Turned a PB, although I was driving pretty conservative after my morning mishap. I will drop the pressures to ~30 next time I'm out on them to see how they work.
https://www.youtube.com/watch?v=O5vY9G0lWi4
I don’t know much about Toyos, but the Michelin engineers told me 26 PSI on the cup 2s every time you roll onto the track. It has worked out well for me.
Racer
Joined: Oct 2021
Posts: 325
Likes: 230
Had a code brown experience with my Toyo R's. To be fair, that was on me as it I just didn't give the tires enough time to warm up.
Started with fairly high hot pressures (36 - 37), dropped them during the day and they seemed to work better around 32 - 33. Turned a PB, although I was driving pretty conservative after my morning mishap. I will drop the pressures to ~30 next time I'm out on them to see how they work.
https://www.youtube.com/watch?v=O5vY9G0lWi4
Started with fairly high hot pressures (36 - 37), dropped them during the day and they seemed to work better around 32 - 33. Turned a PB, although I was driving pretty conservative after my morning mishap. I will drop the pressures to ~30 next time I'm out on them to see how they work.
https://www.youtube.com/watch?v=O5vY9G0lWi4
sorry if I missed it, which PTM mode was this in?
Last edited by MikeR397; Yesterday at 11:47 AM.
Heel & Toe
Joined: Jul 2025
Posts: 15
Likes: 16
To clarify, that was the hot pressure coming off the track. Started at 27 - 28 cold. Kept dropping down during the day.
Toyo recommends high 20's hot for lighter cars, higher pressures for heavier cars. I wasn't sure what it should be on the C8, would love to hear what others have found works well.
That said, these might be the last Toyo R's for me!
Toyo recommends high 20's hot for lighter cars, higher pressures for heavier cars. I wasn't sure what it should be on the C8, would love to hear what others have found works well.
That said, these might be the last Toyo R's for me!
Sr.Random input generator
Joined: Jan 2008
Posts: 7,779
Likes: 2,211
From: Sammamish, WA
To clarify, that was the hot pressure coming off the track. Started at 27 - 28 cold. Kept dropping down during the day.
Toyo recommends high 20's hot for lighter cars, higher pressures for heavier cars. I wasn't sure what it should be on the C8, would love to hear what others have found works well.
That said, these might be the last Toyo R's for me!
Toyo recommends high 20's hot for lighter cars, higher pressures for heavier cars. I wasn't sure what it should be on the C8, would love to hear what others have found works well.
That said, these might be the last Toyo R's for me!
https://www.corvetteforum.com/forums...post1592335627
30 HOT guys, I'm a tire trainer and train with many pro race car drivers.
My R8 with R7s at COTA, I start at 23 cold. There are so many factors at play.... Temps, Type of asphalt, track, driving style blah blah blah.
For example, my front right tire at my local track is always 2psi higher, so I start that tire 2psi lower than the others. Whatever you gotta do to get to 30 hot for a semi slick. 32 hot for a street tire. 30 or below for a real slick.
Straight line braking will heat up your tire the quickest and don't force the heat, heat up
the brakes and tires equally.
My R8 with R7s at COTA, I start at 23 cold. There are so many factors at play.... Temps, Type of asphalt, track, driving style blah blah blah.
For example, my front right tire at my local track is always 2psi higher, so I start that tire 2psi lower than the others. Whatever you gotta do to get to 30 hot for a semi slick. 32 hot for a street tire. 30 or below for a real slick.
Straight line braking will heat up your tire the quickest and don't force the heat, heat up
the brakes and tires equally.
https://www.corvetteforum.com/forums...post1599431991
TL;DR: We use much wider tires than OEM, which (GM) in turn likely uses wider than dictated for load specs for better performance. As such, Hoosier's recommendations are very likely overkill.
As far as I know, Hoosier's recommendation with that formula is actually COLD, not HOT. Yes, that would mean Hoosier wants you to run 37 COLD, possibly hitting 45+ HOT, and they are OK with it exceeding 44 PSI (the max cold pressure listed on the tire), since that limit is for cold, and accounts for pressure increases that happen as the tire gets hot.
https://trackdaytire.com/wp-content/...re_And_Use.pdf
Anyway, we all know (or at least think) that this tire won't work well at those pressures. The reasoning for Hoosier to go with those recommendations is the fact that these tires have much lower load rating than other tires in the same size. However, we actually do not run tires in stock sizes; we run much wider.
Case of C7 Z06 / GS:
Above is all I can say as a fact, but outside Z06/GS, Z51 actually comes with 245/35/19 MPSS ZP tire, a car that is only 150 lbs lighter, which is only rated 89 (1279 lbs), less than 91 (1356 lbs) rated front R7 tire. As such, we're likely safer than we probably think : )
I've been using 25/26 PSI cold with my 315/345 setup, but I also think that it's probably higher than ideal.
As far as I know, Hoosier's recommendation with that formula is actually COLD, not HOT. Yes, that would mean Hoosier wants you to run 37 COLD, possibly hitting 45+ HOT, and they are OK with it exceeding 44 PSI (the max cold pressure listed on the tire), since that limit is for cold, and accounts for pressure increases that happen as the tire gets hot.
https://trackdaytire.com/wp-content/...re_And_Use.pdf
Anyway, we all know (or at least think) that this tire won't work well at those pressures. The reasoning for Hoosier to go with those recommendations is the fact that these tires have much lower load rating than other tires in the same size. However, we actually do not run tires in stock sizes; we run much wider.
Case of C7 Z06 / GS:
- We don't know what GM needs in terms of minimum load rating of the tires used. GM almost certainly didn't choose wider tires for load rating, but for better performance, so more than likely GM's OEM tire choices come with load ratings much more than we need.
- Anyhow, besides speculation, we only know for a fact that the front tires have the lowest rating of the system. For MPSS ZP, it's 94 (1477 lbs).
- A comparable (but a bit wider) R7 at 295/30/19 is only rated at 89 (1279 lbs). However, most track users use 315/30/18, rated at 91 (1356 lbs), which is much closer to OEM tires' rating.
- I don't think we need to talk much about rears, since 345/30/19 is at 98 (1653 lbs), and 345/35/18 is at 100 (1764 lbs).
Above is all I can say as a fact, but outside Z06/GS, Z51 actually comes with 245/35/19 MPSS ZP tire, a car that is only 150 lbs lighter, which is only rated 89 (1279 lbs), less than 91 (1356 lbs) rated front R7 tire. As such, we're likely safer than we probably think : )
I've been using 25/26 PSI cold with my 315/345 setup, but I also think that it's probably higher than ideal.