Street Tire Shootout: Class of 2016

Meet the Newcomers

How can you make a tire faster? The obvious answer is to change the rubber compound so that it better grips the ground. But there’s a tradeoff involved: Generally the grippier the compound, the faster it–and your budget–erodes.

Last year’s crop of performance street tires seemed to hit the point of diminishing returns in that regard, wearing out some 30-percent faster in exchange for their newfound grip. Racers were forced to choose either outright speed or longevity based on their specific event and price point.

Does that mean tire technology has hit a wall? Not at all. Wrapping the right gooey stuff around the rim is’ the only way to make a tire faster. Two new tires, the BFGoodrich Rival-S and the Maxxis Victra VR-1, attempt to push tire performance even further, but they each do so using different strategies.

BFGOODRICH RIVAL-S: Secret-Sauce Construction
Using different belt materials, angles and sidewall inserts can drastically alter a tire’s personality. Making it more responsive, more intuitive and easier to drive can definitely lower lap times.

BFGoodrich recently took this route when it tweaked the internal construction of its smaller Rival-S sizes. If the 2015 version had one flaw, it was numbness; drivers had to lead the Rival-S to the apex almost by guesswork. With the 2016 version, the compound, tread design and belt materials remain the same, but BFGoodrich has modified the way the package is put together.

This sort of running change to a tire model is fairly common in the industry, and it usually happens without any knowledge on the end consumer’s part. Often, the manufacturer only tweaks select sizes of a model. The reasoning? If a certain application highlights a deficiency in the model’s design, then only the sizes most commonly used for that application should get the revisions to address it.

In this case, the update only affects the Rival-S sizes with a three-rib tread pattern. The wider, four-rib tires remain unchanged because they’re typically well supported by wider rims on their target vehicles.

MAXXIS VICTRA VR-1: Going Wide
Another way to go faster is to go bigger. A wider contact patch is almost always faster than a narrower one on dry pavement, assuming it’s supported by a wide enough wheel.

Maxxis, a newcomer to this market segment, focused on the bigger-is-better strategy when creating its new Victra VR-1. The company has chosen to offer the model in some key sizes, including an uncommon 245/40R15. The only other tires offered in this size are R-comps: the Hoosier A7/R7 and Maxxis Victra RC-1. The latter has been quite popular in the track day and time trial communities for drivers of Miatas, Hondas and early BMWs. These are cars that can’t use a taller tire due to wheel well and gearing constraints, and a 225/45R15 was previously the widest 23-inch-tall street tire available.

Warming Up

Before our more rigorous testing began, we had the opportunity to do a casual comparison between our baseline tire and Maxxis’s newcomer.

The Setting: Two different events happened to put us at the same track with the same car just two weeks apart and under similar weather conditions. That track was the relatively fast and challenging Circuit of the Americas in Austin, Texas, and both weekends saw ambient temps in the 70s and partly cloudy skies.

The Plan: For that first event, our trusty One Lap CRX would wear the 2015 version of the 225/45R15 Rival-S. Armed with some solid lap times and data on this baseline tire, we’d then head into our second event, a track day weekend hosted by event company Edge Addicts.

There, we would debut the new 245mm Maxxis Victra VR-1 and try it out on different wheels. On Saturday, we’d mount the 245/40R15 size on 15×9-inch 949 Racing wheels. On Sunday, we’d put them on 15×10s to compare. On both days, we’d use 205/50R15 tires in the rear mounted on 15×8-inch wheels.

While not our typical scientific test, this comparison would afford us a chance to get used to the new tire, explore its strengths and weaknesses, and gather some ballpark timing data. Plus, running full sessions would teach us about the tire’s consistency over the longer run. Think of it as a fact-finding mission.

VR-1 Rim Width: 9 Vs. 10 Inches: After setting out on 9-inch-wide rims, we learned that the VR-1 was a very responsive tire. It was similar in handling to the Yokohama Advan Neova AD08 R that we tested in 2015. It turned in crisply, offered good grip, and provided audible feedback as we approached the limits of adhesion.

A full 20-minute track session of hard driving caused it to lose some of that edge, but the falloff in lap times was minor. COTA’s long straights probably helped by giving the tires significant time to cool off between hard cornering. But long, hard sweepers like Turn 6 and the triple-apex carousel of Turns 16 through 18 did a number on the VR-1 late in each session.

When mounted on 10-inch-wide wheels, the 245mm VR-1 did everything a little bit better: Braking, cornering and forward bite were all improved. The tire was also less susceptible to heat soak because the tread surface was more evenly used. Lap times improved by 0.8 second.

VR-1 on 10-Inch Rims Vs. Old Rival-S: Even mounted on optimal-sized rims, the VR-1 seemed to be no match for the old Rival-S, falling more than a second short of the baseline tire on the long, 2.5-minute lap.

Digging deeper, the datalogger confirmed the big time differential in sustained sweepers. It also showed that the Rival-S was better at accelerating onto the long straights. Some of this was just due to the tire more efficiently putting down power out of a decreasing-radius corner, but as the speeds increased, the acceleration curves diverged.

VR-1 on 9-Inch Rims Vs. Old Rival-S: We then compared the same straightaway data for the VR-1 on the 9-inch wheels and found it had no such divergence. We believe that the aero disadvantage due to that extra inch of rim width was worth almost 4 mph and 0.7 second down the back straight.

Wheel well spats or some nice flares would mitigate the tires’ protrusion, but the increased frontal area is still there regardless. Perhaps the big 245mm VR-1 would stand a better chance on shorter tracks?

Test Day 1

To get more precise answers to our questions, we next headed to our usual test track.

The Setting: Harris Hill Raceway, found nestled in the hills south of Austin, Texas, is a typical club-type track with lots of runoff. It’s roughly half the length of COTA, with speeds not exceeding 115 mph. We’ve logged countless hours here, most of them in the CRX.

Of late, the surface has gotten a fair bit rougher due to heaving from heavy flooding. A new bump at the apex of the back straight’s kink as well as a few recent ripples in the fast Turns 9 and 11 have unfortunately added “driver bravery” to the set of control variables. Add in some initial dirty spots from recent rain runoff, and we had to do some interpolating when analyzing this data.

THE PLAN: First, we’d find the ideal rim width for the VR-1. Then we could start comparing some tires. Our reigning track champion from last year’s test was the 225/45R15 Rival-S mounted on 15×9-inch wheels. We chose that tire as our control throughout our test, setting baseline times and bracketing at the end of the day to measure the effects of changes in the weather, track and driver. In between, we’d see how the old Rival-S held up against the VR-1 as well as the revised version of itself.

VR-1 Rim Width: 9 Vs. 10 Inches: We ran the 245mm VR-1 on both 9- and 10-inch-wide rims to quantify the value of the extra inch of sidewall support. The datalogger showed big gains on the wider wheels in straightaway speeds thanks to earlier power application on corner exit. Braking was also better on the wider rims, with a combined improvement of approximately half a second.

VR-1 Vs. Old Rival-S: Does the larger 245mm VR-1 have what it takes to beat last year’s 225mm Rival-S, both on their optimal rim widths? A back-to-back test showed that it was close, but the old Rival-S was still quicker by a few tenths. Almost all of the advantage came thanks to higher mid-corner speeds. The Rival-S simply seemed to grip better. Unfortunately for Maxxis, BFGoodrich’s newly revised version is only harder to beat.

Old Rival-S Vs. New Rival-S: We back-to-back tested the 2015 Rival-S with the new version to evaluate any improvements. First, the big news: Bravo, BFG! The revised Rival-S was more than a half-second quicker than the earlier release. The improved steering response felt more natural and linear, inspiring confidence on corner entry despite the track’s bumpy surface.

More importantly, we could better apply power as we came off the turns because our front tires more easily combined the tasks of steering and accelerating. On the earlier Rival-S, we had to wait until the steering wheel unwound a bit more to add throttle.

Test Day 2

After a good night’s sleep, we refilled our gas cans, swapped out some tires, and headed back to Harris Hill for a size-for-size comparison.

The Setting: An earlier start time gave us cooler temps, while Harris Hill’s track surface was a bit cleaner and stickier. As a result, all the lap times from day two were faster than the ones from day one–despite the narrower tires. So we ignored any temptation to compare the two days’ results.

The Plan: This time, we wanted to do a strict comparison of the Maxxis Victra VR-1 against the two standouts of last year’s test: the earlier BFGoodrich g-Force Rival-S and its formidable competitor, the Bridgestone RE-71R.

All tire and wheel sizes would be identical for this session: narrower 205/50R15 rubber on 15×8-inch rims. We would have loved to add a 205mm version of the new Rival-S to the mix, but it was not yet available. We’d use the 2015 version in that size instead. This would be basically the same test we did last year, but with the new VR-1 in place of the Dunlop ZII Star Spec.

RE-71R Vs. Old Rival-S: The short answer is that nothing really changed in the pecking order from last year. Size for size, the RE-71R is still quickest for a three-lap time trial over the old Rival-S–but just barely.

VR-1 Vs. Last Year’s Top Tires: Where did the VR-1 fit in? It was about a second slower than those first two, which puts it right at the same deficit we found last year with the other previous-generation tires, like the Dunlop Direzza ZII Star Spec and Yokohama Advan Neova AD08 R.

We did notice that the VR-1 in the 205mm size was simply too little tire on the nose of our high-powered CRX. It overheated by the third lap when pushed hard and was howling under load by the time we were done, with a resultant hit to lap times. That said, it should be noted that the VR-1 comes molded to a 9/32-inch tread depth, which could be a contributing factor to the heat soak when not shaved or worn.

Drawing Some Conclusions

What did we take away from comparing these tires on track? And how will that influence our approach as we head to the autocross course for phase two of our testing?

Rival-S: BFGoodrich has clearly made good on its promise to evolve the Rival-S. The revised tire carves to the apex better and in a more direct fashion. It also allows our front-drive CRX to better put down power out of corners. The steering wheel can be unwound sooner, reducing the understeer that usually results from weight moving off the nose of the car. All of these improvements save time.

The earlier Rival-S is already at the front of the field for its time trial prowess, but these advances in the new version raise the bar yet another notch. The rubber won’t last any longer, but you’ll be going faster while it does.

VR-1: Maxxis also has a winner in its new market entry. While not the quickest in a time trial format, the VR-1 will likely deliver big in longer crapcan races. With 9/32-inch of tread to burn and lap times that appear to be on a par with other enduro street tires, a single set should be able to bring teams to the front over an entire weekend of racing. Add in the unique 245/40R15 size, which is ideal for many of these low-budget cars, and you have the makings of a winner.

What About Autocross? Next issue, we’ll hit the autocross course to find out how the new tires stack up in an environment where quick changes of direction and precise car placement reign supreme. The new Rival-S’s improved steering response will likely be even more valuable there, but so will the size advantage of the 245mm VR-1. Stay tuned.

Sources

949 Racing: 949racing.com, (949) 716-3111, wheels

BFGoodrich Tires: bfgoodrichtires.com, (877) 788-8899, tires

Bridgestone Americas Tire Operations: bridgestonetire.com, (866) 775-6480, tires

Circuit of the Americas: circuitoftheamericas.com, (512) 301-6600, warmup track

Harris Hill Raceway: harrishillroad.com, (512) 667-6250, test track

Maxxis: maxxis.com, (800) 4-MAXXIS, tires