Intermediate Topic #1: training wheels

Here in California, there isn’t much off-season, but for a lot of YSAR readers the driving season is just starting. Each year, I have specific driver development goals. I hope you do too. With that in mind, I thought I would do a series of posts aimed at the intermediate driver who wants to improve their craft in 2019. Let’s identify and fix some common errors. If you’re not an intermediate driver, fake it.

So many tires

What tires should you bring to an HPDE track day? Popular choices include Hoosier R7, Nitto NT-01, Toyo R888R, Maxxis RC1, etc. There are literally dozens to choose from. Myself, on a race track, I’ve driven on a bunch of different compounds made for sporty driving and several others that were definitely not. For those who like lists, here they are to my best recollection: BFG Rival; Bridgestone RE71R, RE11A; Continental ECS; Douglas Xtra Trac II, All Season, Performance; Dunlop Z1, Z2; Falken RT615, RT615K, RT615K+; Federal 595 RSRR; Goodyear Eagle Sport; Hankook RS3, RS4, H724; Hoosier SM7; Nitto NT01, NT05; Pirelli P6; Riken Raptor; Toyo RR, RA1; Yokohama S.drive.

Which stops best? Which turns in best? Which has the lowest lap times? Which feels best? Since the ‘E’ in HPDE stands for education, what we really should be asking is which one is most educational? In other words, which tire will make you a better driver? If you’re trying to improve your driving skills, your primary goal is to learn how to sense and control traction. As a student of driving, it’s literally your job to find out what’s on the other side of the slip angle curve. You know, the part where it dips down and gets less grippy.

Compliance

Tires are effectively part of your suspension. In the “it’s raining lies” series, we discussed why you soften the suspension in the rain. In a word, compliance. Drivers need time to adapt to changes in grip. Intermediate drivers, who aren’t comfortable sliding their car around, need time to explore the traction space. Your job as an improving driver is to play around on the unfamiliar side of the slip angle curve. If you’re not making steering corrections, you’re not sliding enough, not exploring enough, not learning enough. Am I telling you to spin out on track? No. If you find yourself spinning, you’re getting surprised by loss of traction. To combat that surprise you need tires with more compliance.

Slip angle

How much difference in compliance is there among different kinds of tires? In other words, how much does traction change with slip angle? Take a look at the following graph. Racing tires have the most grip, but they also have the most change in grip. Once the optimal slip angle is exceeded, grip falls away very quickly. On the opposite end of the spectrum is the street tire. It has low grip, but a very gradual loss of traction. As a result, intermediate level drivers are better served with street tires than R-comps.

Some of you are probably thinking “But I want to drive on R-comps some day, so I ought to be driving on them all the time”. I can see the logic in that, but your muscle memory does not. There’s a reason why the best motorcycle racers have dirt racing backgrounds. If you want to improve your driving, you need to experience more sliding, not less.

Sound

A critical part of your grip-sensing toolkit is your ears. The sound of your tires is a language you will eventually understand at a higher resolution than the following quote I got from my racing buddy Ben.

A squealing tire is a happy tire. A screaming tire is a screaming tire.

The fastest way around a corner requires balancing tire grip throughout the corner. Use too much too soon and the tire will lose traction in the second half of the corner. How do you monitor that? Got an APEX Pro? Its lights tell you how much grip you’re using. Don’t have one? No problem, your ears do the same thing. Street tires tend to be narrower than R-comps. The extra load and open tread means that street tires are louder. If you want to hear what your tires are doing, and really you do, you should be training on street tires. Again, some of you are thinking, “but some day I want to use R-comps, so I should be training myself for that sound”. You know who’s talking? That part of your ego that doesn’t want to run slower laps. Don’t let your ego hold you back from actually improving.

Don’t believe me? How about Skip Barber?

Despite recent financial problems, the Skip Barber racing school is the most famous racing school in the USA if not the world. They have been training drivers in Formula Fords since the 1970s. Guess what tires they mount on their school cars? Street tires. How streetable are we talking about? 400 treadwear BF Goodrich T/A Radial at last reckoning. If the #1 racing school uses street tires on its Formula cars, maybe you should consider the same on whatever you happen to take to the track.

As a side note, when I was researching the T/A Radial, I read a bunch of reviews to see what people thought of them. You know what the #1 complaint was? No, it wasn’t problems with durability or grip, but rather the white lettering on the sides of the tire. Apparently they aren’t white enough and if you scrub them too much it rubs off. Oh for fucks sake, who the hell buys tires because of the lettering on the sides? Apparently lots of people. This reminds me that there are two kinds of car people, (1) the kind that wash their cars (2) the kind that drive their cars. If you’re the first kind, thanks for stopping by a blog about the second kind.

Which street tire?

On my Yaris I’ve used everything from Hoosiers to Hankook runflats. One of my favorites is Douglas Performance in 195/55/15. The Douglas Tires brand is probably not one you’re familiar with. They are actually made by Goodyear in their Kelly Springfield subsidiary plant. Douglas currently makes only 2 models of tires: All-Season and Performance. Both come with 420 treadwear ratings and a 45,000 mile warranty. They cost about $40-45 each. On track, I’ve found them to be more heat resistant than some performance tires. How do they perform? Like a 420 treadwear tire, so perfect.

 

My brother has his street/track Miata set up with Yokohama S.drives. At 300 TW, that’s a bit sportier than a Douglas, but a great choice because it’s loud and has a nice balance of grip and slip. I think 300 is a good compromise, but if you’re not sure, here’s a suggestion: OEM tires. That’s what your car was designed to use. And as my friend Harkamal used to say, you should always run in jeans because if you ever have to run for your life, you’re probably going to be wearing jeans.

Are you ready to leave your ego in the paddock? Are you willing to make short-term sacrifices for long-term gains? Sadly, most drivers are not. Let’s face it, even though HPDE sessions don’t allow racing, it’s always a race, and nobody wants to be slower than the next guy. No problem, just bring 2 sets of tires to the track. You’ll be grinning ear to ear when you pass people in faster cars with your training wheels on. Don’t be surprised if you find yourself leaving them on the whole day.

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