Proxes R888R

[911 Rod]

Hello,

I bought a set of R888R's for my 86 in 245/45/16 and 225/45/16 as these were the only brand available in these sizes.

I've been tracking my RS-3's but I think they are toast after about 40 track days.

Any advice on tracking the new R888R's? Tire pressure? Will driving them on the street and track be problematic for tire life?

Thanks

[bdonally]

Hi Rod
I put on a set of 888R's last spring, so have a season on them.
As far as street/track, they are a bit noisy, and there aren't many grooves so you have to be a bit careful if there is much water.
But then we all drive conservatively off the track, right.

On my car I use 35 front/37 rear hot. I prefer a little understeer and the slightly lower front pressure suits me.
My car is set up with 2 degrees negative camber on the front and 2.5 degrees on the rear.
I had a chance to fool around with a tire pyrometer at an track day and I found that the temperatures were within 5-10 degrees F across the face of any tire.
The fronts were 180-185 (left) and 170-175 (right)
Rears 195-200 left and 185-190 right.
From this, I decided that the camber setup is about right, and the pressures are OK as the temperatures are around the middle of the range recommended by Toyo.

https://www.toyotires.ca/tires/proxes-r888r-dot-competition-tire

I haven't used them extensively on the street but with previous tires I found that the inside wear due to camber in street driving sort of evened out the outside wear from the track.
There has been some discussions about the aging effect of street driving; for us DE guys with old cars I think the following chart is the best determinant of tire life:

[Elombard]

Love that chart!

[WP0ZZZ]

There is nice setup advice from Toyo in the link that bdonally provided. I paste it here for convenience:

SETUP GUIDELINES
Operating Temperature: 71°c to 104°c (160°F to 220°F)

VEHICLE WEIGHT
COLD INFLATION PRESSURES
HOT INFLATION PRESSURES

Less than 800 kg.
17 - 22 psi
22 – 29 psi

800 kg. – 1000 kg.
20 – 26 psi
24 – 32 psi

1000 kg. – 1400 kg.
23 – 27 psi
28 – 40 psi

More than 1400 kg.
27 – 35 psi
37 – 42 psi

Camber: -1.0° to -3.0° (the Proxes R888 generally requires less negative camber than the Proxes RA1)

Caster: As much positive as possible

Shaving: 4/32” is recommended for competition (grooves remain until 2/32”)

Rim width: a tire size that falls within the range of midpoint to maximum rim widths is recommended

Wet conditions: increase tire inflation pressure by 6-10 PSI to reduce the possibility of hydroplaning

Driving style with less slip angle is recommended (when compared with the RA1)

Break-in procedure for new R888 at full tread depth: scrub the tire clean of any mold release chemical. Bring new tires (full tread or shaved) up to operating temperature gradually over the course of a few laps to minimize graining


PROXES R888 SAFETY ADVISORY

The tread compound is specifically designed to operate under racing conditions making it difficult to achieve optimum adhesion levels under normal street driving.
The shallower tread depth of 6/32nds limits the tire’s performance capabilities under normal street driving conditions.
Performance limitations are particularly evident in low ambient temperatures or during the spring and fall when ambient temperatures fluctuate significantly.
Wet performance is limited when operating outside the optimum temperature range, and when the tire is at less than full tread depth.
Do not use the tire if it has cracked.

[juanbenae]

I never ran them, but was racing a spec911 with prc when they 1st came out and the RA1 was to be phased out with their introduction. full disclosure the RA1's we ran were always shaved where as the R888 was not suppose to be according to toyo.

what a number of drivers that tested them the off season before they were to become an and/or tire for the SP911 class they were hated. not the warning the RA1's would provide at the limit, they got greasy quickly, got dangerous and slowing would not help in getting them back & cool from the reports shared. worse yet after just a few heat cycles they were junk compared to the RA1. as it turned out the spec miatas din't necessary care for them and the RA1 was thankfully not discontinued.


I suppose they might be fine as a DE tire, but under race conditions with #2400 pound 911s they were less than effective.

[danco_]

Did you test the R888 or the new R888R?


I can't imagine Toyo changed the composition in them, but I'm still curious.

Thanks

Originally Posted by juanbenae

I never ran them, but was racing a spec911 with prc when they 1st came out and the RA1 was to be phased out with their introduction. full disclosure the RA1's we ran were always shaved where as the R888 was not suppose to be according to toyo.

what a number of drivers that tested them the off season before they were to become an and/or tire for the SP911 class they were hated. not the warning the RA1's would provide at the limit, they got greasy quickly, got dangerous and slowing would not help in getting them back & cool from the reports shared. worse yet after just a few heat cycles they were junk compared to the RA1. as it turned out the spec miatas din't necessary care for them and the RA1 was thankfully not discontinued.


I suppose they might be fine as a DE tire, but under race conditions with #2400 pound 911s they were less than effective.

[911 Rod]

Thanks for the info gents.

Please confirm you are talking about the new R888R and not the old R888.

I have the R888R. My understanding is that the composition is quite different.

[Mr. Merk]

I put a brand new set of these (same sizes) on my 8" & 9" wheels before driving to Luft5 from Arkansas via Colorado, Utah and SF.

When I got home 12 days later we had put about 5200 miles on them. The rears were starting to show secondary rubber in the middle. I assume the pressures increased at high elevation and also while driving across Utah & New Mexico at 115mph.

The tires are really loud now due to some bad alignment cupping in the front but still have plenty of grip although the balding rears are getting a little slippery

Performance wise they did fine in a little wet weather. We even encountered some snow at Donner pass, which was terrifying and the most stressful driving experience of my life. We REALLY pushed them while driving the canyons north of LA and the grip was mind blowing in my mostly stock and heavy Carrera, always two passengers and often fully loaded with luggage. Driving through Vegas, we had an emergency stop at highway speeds and I felt like I was peeling up the concrete. The tires stopped the car very quickly.

I'll probably put another set on in October before going to Targa Carolina.

[WP0ZZZ]

What's your impression of the R888R on the road? Is it hard to get them warm enough?

[juanbenae]

Originally Posted by danco_

Did you test the R888 or the new R888R?


I can't imagine Toyo changed the composition in them, but I'm still curious.

Thanks

as I'd stated I never did run them, and the reports I note were from the original R888. I was not aware there was a second version so my example may be less than relevant with the S version.

[911 Rod]

2 days on the track and I found 34 all around worked. Any more in the back and I found things a little squirly going through the es's.

[Mr. Merk]

Originally Posted by WP0ZZZ

What's your impression of the R888R on the road? Is it hard to get them warm enough?

Not at all, when driving to work I hit a round-about about 4 minutes from my house and there is plenty of grip!

[911 Rod]

I do not find them noisy at all.

[911SauCy]

Originally Posted by 911 Rod

Thanks for the info gents.

Please confirm you are talking about the new R888R and not the old R888.

I have the R888R. My understanding is that the composition is quite different.

I'm friendly with a local shop owner who advised against the 888s...until the Rs were released. Almost all of his customers use them and he was explaining the night/day difference versus the earlier comps.

I'm picking up a set this week

[safe]

Originally Posted by 911 Rod

2 days on the track and I found 34 all around worked. Any more in the back and I found things a little squirly going through the es's.

That equals my experience with the old R888, so maybe not that big difference.
I keep them around 32 in the rear and 30-32 in the front.
34-35 that gets really greasy...

But I think these numbers are the same for most r-compounds.

[puddy]

I've been using R888's for the last 3 years, and have just went to R888R on my rears. I'm looking forward to trying the new tires.

One thing i've never had a problem with but i've heard other people complain about tire noise on the R888s. My hotrod is loud enough that tire noise is not a problem.

[Helix8]

Originally Posted by safe

That equals my experience with the old R888, so maybe not that big difference.
I keep them around 32 in the rear and 30-32 in the front.
34-35 that gets really greasy...

But I think these numbers are the same for most r-compounds.

Are these hot values or cold? Thank you

[manbridge 74]

Haven’t used them much below 60F but they grip well. Getting them to slide on the streets would surely get you into higher traffic citation probability.

[safe]

Originally Posted by Helix8

Are these hot values or cold? Thank you

Hot.
But its the same for "cold", when drivning on the street.