Every tire test we conduct represents but a single data point, and though we try to minimize variables in our comparison process, there will always be the chance that different results will be obtained with different weather, venue, driver, vehicle and setup. So what do we do? Test again.
Round 1: Yokohama vs. Hoosier
We were given permission to share partial results from our private developmental work that compared a new tire to both the Hoosier R7 and Yokohama A055. In that test, the prototype tire was run at both the beginning and end of the test, and while we can’t divulge the actual data, the two sessions produced similar results, so we’re confident that we successfully minimized variables in our comparison.
For logistical reasons, we lapped Harris Hill Raceway, our usual track for tire testing, in the atypical counterclockwise direction. Weather was cloudy throughout with temperatures hovering in the low 70s.
Yokohama Advan A055
- size: 245/40R17
- fastest lap: 1:25.02
The Advan A055 came up to temp rather quickly, and full grip was available after about a lap and a half. Steering response was extremely progressive, with small inputs making increasingly larger turning moments as cornering loads increased.
Breakaway was a little edgy, especially at the rear of the car. This required constant attention to consistently drive at the limit, but the tire’s pace never slowed. Looking at the data, there was no more than a tenth or two available by combining the best sections.
Hoosier R7
- size: 225/40R17
- fastest lap: 1:25.08
The R7 took several laps to build heat and fully activate the compound. Driving characteristics were very natural: medium response, progressive breakaway. The tire was especially good at combined loading asks–like trail-braking along with corner-exit power-up.
Handling balance shifted to a slight oversteer, though, resulting in a spin on the fourth lap in Turn2. It’s an especially tricky section to get consistently in the clockwise layout, requiring trail-braking, a downshift and a subsequent power squeeze just as the car crests some bumps. Add tire swaps to the equation, and mistakes can happen.
Unfortunately, the spin overheated the rear tires, and subsequent laps did not deliver the same level of grip. Looking at the data, though, the quickest lap had all the best segments.
Round 2: Adding Goodyear to the Mix
When talking R-comps, what about Goodyear? We’d been told that its Eagle RS DOT recently received an updated compound.
A month later, a perfect weather window opened up just after the new Goodyears arrived. With those mounted and heat-cycled, we loaded them up along with our two-cycle Yokohamas and Hoosiers. This would possibly give a slight advantage to the Goodyears, but given how far back they placed in the last test, we were okay with that.
Test day dawned in the low 50s, with temps climbing to 60 through our morning of lapping. Tires were kept in our motor home at about 70 degrees until called to action. We ran Harris Hill Raceway in our usual counterclockwise direction.
Goodyear Eagle RS DOT
- size: 225/40R17
- fastest lap: 1:27.4
Despite the low track temps, the Goodyear compound turned on immediately. Response of the Eagle RS was a bit sluggish compared to the others, however, and breakaway was vague.
Much as it did last year, though, the Goodyear delivered strong longitudinal grip–both braking and putting down power–but only when the steering wheel was mostly straight. Combined loading was not its strong suit, nor was mid-corner grip. It was especially unhappy in Turns 2 and 5, where hard braking is quickly followed by uphill, off-camber turning.
Hoosier R7
- size: 225/40R17
- fastest lap: 1:25.4
As before, the R7 took a little time to come in but then delivered some consistent laps before falling off a bit. Data analysis showed about two more tenths available for the perfect lap.
Yokohama Advan A055
- size: 245/40R17
- fastest lap: 1:25.0
Yet again, the Yokohama was very consistent and fast after a single warmup lap. Per the data, nothing was left on the table on that single flyer.
Goodyear Eagle RS DOT (retest)
- size: 225/40R17
- fastest lap: 1:27.2
Thanks to the added familiarity, we were able to extract a bit more pace out of the Goodyear on the retest, but doing so put so much heat into the tire that it fell off sooner than in the earlier session. Still, it was close enough that we were comfortable that track evolution was not a factor in our results.
Who Won This Round?
The big takeaway from this year’s testing was the pace and consistency of the Yokohama Advan A055. When physical sizing is taken into consideration, it is the equal of the vaunted Hoosier R7–and that is saying something.
This makes the Yokohama a strong option for classes like NASA Super Touring that govern via sizing templates, or in cases where physical wheel well packaging is the defining limit. Given the distinctly different handling characteristics, both the Yokohama and Hoosier should be tried to see which best matches the car and driver.
Sadly, we just never connected with the updated Goodyear. On a relative basis, it was no quicker for us than last year, and the accelerated wear was concerning. While the pattern was fairly even, suggesting our pressures and camber were good, it was heavily grained. We even ran them again a couple of days after this test in warmer weather with no better results. At that point, with only 40 laps on the clock, the tread cap began to wear through.
But Goodyear has had good success at the SCCA National Championship Runoffs on big cars with big power, so perhaps we just need a faster test mule to find its sweet spot. That said, they were recently selected as the spec tire for SCCA’s B-Spec class of small, low-powered, front-drive econoboxes for 2024. We’ll be watching closely.
