Tire Tests: Toyo Proxes RR And Proxes R888R On Track And Autocross

When you are trying to improve your car’s performance, the first thing you should be looking at is the tires. Those four black donuts on your wheels are what translates everything you want to do with your car to the reality of the road. You say you want to run a sub-two-minute lap around Buttonwillow Raceway? It’s not going to happen unless you have some very sticky tires. Good news: Toyo Tires makes sticky tires.

Toyo Proxes RR

The Toyo Proxes RR is the go-to tire for road racing and has earned numerous championships. Currently, it is the spec tire for NASA Camaro-Mustang Challenge, Honda Challenge, Spec E30, and Spec Miata. (Lead Photo above: Jane Absalom. All other photos: Shawn Brereton)

When it comes to track duty, the Toyo Proxes RR has proven itself over and over again, bringing home wins for numerous race teams and many championships. Drivers who use the RR, and have Toyo Tires stickers on their car, can earn Toyo Bucks, which helps buy tires for the next event.

The RR tire is essentially a racing slick with two adjacent grooves in the tire to make it DOT compliant (a requirement for many racing sanctioning bodies). Regardless of the two grooves, one look at this tire and you can see it was built for dry track conditions. For wet conditions, you would want to switch to the Toyo Proxes RA1 or R888R, which we will discuss here shortly.

The sidewall construction of the Toyo Proxes RR is what really delivers the performance and responsiveness for which the Toyo RR is known.

Toyo Proxes RR Specs:

DOT Legal: Yes
Treadwear: 40
Weight (205/50R15): 20 pounds
Maximum Pressure: 51 pounds

Toyo says these tires do not need to be shaved. However, they do prefer them to be heat-cycled once and scuffed-in before racing use. Senior Manager of Motorsports at Toyo Tires, Marc Sanzenbacher, provided recommendations for tire pressure for the RR, “This tire likes to be between 32 and 38 pounds, hot.”

Track tests have shown these tires will be a bit slippery when cold, but the heat comes in quickly (within one lap) and then remains consistent. When temperatures get too hot for the tire, beyond 220-degrees Fahrenheit, then they can provide a slick feel. The key is to keep the tire inside its happy temperature range (between 160- to 220-degrees) during a race. Then it will remain nice and sticky, allowing you to carry lots of speed through corners, and hopefully win some races.

For our tire test on our Project CrossTime Mazda Miata, we started at 26 pounds cold, knowing as the tire warmed up, the pressure would increase within the range (32 to 38 pounds) that Marc Sanzenbacher from Toyo recommended.

We slapped a set of new Toyo Proxes RRs on our Project CrossTime Miata and headed out onto the track at Memphis International Raceway (MIR) to run a NASA Spec Miata race. Shawn Brereton was our wheelman for this event, and he found the tires very predictable. “The tire was very easy to drive on,” said Shawn. “I could feel the edge of adhesion approaching, so I always knew where the limit was. These tires won’t surprise you with a sudden loss of traction. There is plenty of warning, which is nice.”

To compare lap times and tire performance during the test, we used a Racepak Vantage which provided data directly to a cellphone, and simultaneously to the cloud, where we could access and view it on a tablet in the paddock.

As Shawn was peddling the Miata around MIR, we were looking at data from his car live on the cloud via a Racepak Vantage CL1 data acquisition system in the vehicle. The Racepak provided us live lap timing, g-forces, and miles per hour. Right away, we could see Shawn’s mile per hour on corner exit was faster on the Toyo Proxes RR tires, indicating he was able to carry more speed into each corner thanks to the adhesion of the tires.

Shawn was extremely happy that he (well, his buddy Chris) bolted on a fresh set of Toyo Proxes RR tires because his car was faster on track immediately.

During the Spec Miata race main event, Shawn found the predictability of the tires allowed him to drive hard and consistent during the race. Shawn was within two-tenths of a second per lap, which says a lot about him as a driver, and about the Toyo RR and its ability to be reliable. The new tires were a welcome addition to the Miata and helped Shawn earn a podium finish in Spec Miata.

Shawn ran super consistent and picked up a podium finish in Spec Miata while testing a fresh set of Toyo RRs. (Photo: Jane Absalom)

The results of the Toyo Proxes RR test was, “They were great.” Of course, Shawn thought they were great, they helped him get a Spec Miata trophy, and he earned Toyo Bucks for finishing in the top three. The only question was, with the slick design of the RR, what would Shawn do should light rain be in the forecast? Good news again from Toyo: they have that covered with the Toyo Proxes R888R.

Toyo Proxes R888R

The tread pattern on the Toyo Proxes R888R is built for maximum traction but it is also designed to help excurse water from under the tire to avoid hydroplaning.

At TURNology, we have covered all of the information you will find on a sidewall of a tire and what it means in this article HERE. That article covers the treadwear rating, which is important to understand because it is one of the significant differences (besides the tread pattern) of the Toyo Proxes RR and the Toyo Proxes R888R.

The RR has a treadwear rating of 40, while the R888R has a treadwear rating of 100. Both of these treadwear ratings indicate these tires are incredibly soft. For comparison, the average daily-driver SUV is equipped from the factory with a tire rated at around 500 treadwear. The 100 treadwear rating of the R888R is so soft; in fact, it isn’t legal to run in the SCCA Solo Street Class, which requires a 200 treadwear tire to compete.

The internal structure of the R888R is very similar to the RR. However, the rubber compound is a bit harder (100 treadwear for the R888R versus 40 treadwear for the RR). For both tires, Toyo recommends a negative camber setting of 1- to 3-degrees.

Toyo Proxes R888R Specs:

DOT Legal: Yes
Treadwear: 100
Weight (205/50R15): 20 pounds
Maximum Pressure: 50 pounds

Toyo describes the R888R (commonly referred to as the R-Triple 8-R) as a tire that “features an R-compound tread that quickly reaches operating temperature and provides high-grip levels for maximum cornering traction. The tread compound is molded into an aggressive, asymmetric tread pattern with massive outboard shoulder blocks to provide the lateral grip needed when driving on the track.”

It was time for us to find out if any of that corporate jargon was true by slapping on a set of Triple-8Rs onto the Project CrossTime Miata and having Shawn Brereton hit the track again.

We bolted on a sticker set of Toyo Proxes R888Rs to the workhorse Miata, torqued the wheels, set the tire pressures, and headed out to destroy some tarmac.

We wanted to test the Toyo Proxes R888R in a wet setting, so when the clouds darkened, we headed to an SCCA autocross to dodge some cones and see how the tires did. Shawn was again our test pilot driving his Miata. He set the pressures at 26 pounds for the first set of runs and immediately went hard and fast around the course to find the limits of the R888R.

For our Toyo Proxes R888R test, we again used our Racepak Vantage to look at data, create track maps, and see the improved performance from the tires.

At the first curve, Shawn found that the Toyo R888R didn’t have quite the same grip as the Toyo RR. However, some of that could be attributed to a damp autocross parking lot surface versus a dedicated road course. As the event continued and heat built up in the R888R, Shawn located more confidence in the tire and found it was doing what he wanted as he tossed the Miata around the cones and used as much grip in the tires as was available.

In the slalom section, Shawn was able to mat the gas pedal to the floor and zig the Miata around the cones fearlessly thanks to the grip provided by the sticky R888R tire. Run after run, Shawn began to trust the tires more and drive the car harder, which the tires seemed to appreciate. In the end, they rewarded Shawn with a First-place PAX finish in the CSP class and Third overall in RAW time.

The results from the autocross speak for themselves and the performance of the Toyo Proxes R888R tire — First place in the SCCA CSP class and third-fastest-time overall for the entire event, less than one-second behind!

Shawn, on the R888R, took First Place in the CSP class and then finished Third overall for the entire field, which is an impressive statistic. The only cars that were faster on course was a lighter Honda CRX and a Ford Fiesta ST, which we know from our other project car “The Way of the FiST” are always super-fast around autocross tracks, and a seasoned national Solo racer drove this one.

The End Of The Day

“The conditions were crazy,” Shawn said. “It started cold and wet and ended dry and warm, but the R888Rs kept me from having to switch tires. Though they weren’t heating up quite as quickly as I thought they would, I dropped the pressures to 24 pounds, and they really came alive. They started sticking after the first couple of turns, and I was able to hammer on them after that. I think the beauty in this tire is it shows signs of lasting me the entire autocross season, unlike my dedicated 200 treadwear tires from last season. And that is a major factor for me because I know I will need more road course tires before the end of the season, and I can’t afford a second set for autocross, too. I’ll give up a tenth of a second for that any day!”

The Toyo Tire Proxes RR and Proxes R888R tests were both successful, picking up podium finishes in two different classes, and in two different types of races.

At the end of each day of tire testing with the Toyo Proxes RR and the Toyo Proxes R888R, we were thrilled. On the RR, we earned a podium finish in a Spec Miata road race at MIR. On the R888R, we won the CSP class and finished in the top-three overall at an autocross.

The Toyos performed flawlessly and allowed our hot shoe driver, Shawn Brereton, to throw his Mazda Miata around some racecourses with reckless abandon. All of this fun thanks to Toyo Tires, and we earned some Toyo Bucks in the process because we had our requisite Toyo Tires decals on the Miata at the track. That is a win!

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About the author

Rob Krider

Rob Krider will race absolutely anything. He is a multi-national champion racing driver and is also the author of the novel, Cadet Blues.
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