How fast are you?

This page provides a few ways to measure your driving skill. You may find this useful to track your improvement over time (or not). Hopefully you find it entertaining if not informative.

The Lime Rock Benchmark

Lime Rock Park is a simple 7 turn track that is easy to learn and difficult to master. Because it  is one of the free tracks in iRacing and is raced every 4 weeks in the MX-5 series, it is very well known by all iRacing drivers. This benchmark is based on simulation, but we can get a general picture of driver ability by examining the data.

Here’s a plot showing the qualifying times at Lime Rock in the MX-5 series in iRacing (2015 S1 W3). 1315 drivers did qualifying sessions. Many people race without qualifying, especially rookies, so this plot is skewed towards people who are more serious about racing (hopefully that’s you too). The shape of the curve is not exactly a bell curve. There’s an upper limit to how fast one can drive, but no lower limit.


Only 20 people went faster than 60 seconds. This top 1-2% of drivers are colloquially referred to as aliens because they don’t appear to be human. The median time is 1:01.682 while the average is 1:01.953 with a standard deviation of 1.464. At Lime Rock, fast is below 1:01 and slow is 1:04 or more. If you’re in the 1:01-1:03 range, you’re good.

Racecar Driver Ranking System (RDRS)

With inspiration from the National Tennis Ranking Program (NTRP), I present a driver ranking system that describes various levels of driving skill. In addition to the numerical rating, I’ve also added a descriptive label. Numbers and text aside, what really matters are lap times and podiums.

Level 1: Commuters. Drivers at this level drive mostly because they have to, not because they enjoy it. Their favorite part of driving is probably listening to music. When choosing a car, they may prioritize status, comfort, fashion, utility, or economy depending on their personality. On the street, these drivers tend to be safe except when distracted by things going on inside the car, like texting. On a race track, these drivers have no conception of the driving line and are so focused on the track ahead that they don’t look in their mirrors.

Level 2: Enthusiasts. These drivers love their cars and the experience of driving them. Enthusiasts gravitate towards sports cars and can quote performance metrics and engine specs from memory. Looking fast can be even more important than going fast, which is why their cars may have aftermarket spoilers, excessive camber, lowered suspension, and custom paint jobs. On a race track, these drivers follow the driving line, albeit at low G-forces. 2.5 level drivers begin to slide their tires and may become fascinated with drifting. On the street, these are the most dangerous drivers because they think the street is their playground.

Level 3: Track Junkies. Drivers at this level love to go to track and autocross events. Their cars are set up for actual performance rather than just the appearance of it. 3.0 drivers are learning how to put advanced techniques such as heel-toe shifting, trail-braking, and left-foot braking to practical use. They also begin to experiment with tuning. Wheel-to-wheel racing experience is limited, however, and they may be dangerous in high-traffic or wet weather. 3.5 drivers begin to attack the track and may aggressively slide their tires, though often not optimally.

Level 4: Club Racer: 4.0 drivers often have their own purpose-built racecar which they bring to local competitions. They have learned most advanced driving techniques and understand how to tune their car to optimize handling. Lap times generally fall within the same second or two, but they still make frequent minor errors which they may be unaware of. When trying to improve their driving, they tend to focus on the physical rather than mental side. In a regional race, they run a few seconds off pace in the middle of the pack. 4.5 drivers are more consistent (all laps within the same second) and may find themselves on a podium from time to time.

Level 5: Semi-Pro. Racing is an obsessive hobby, but not a full time job. 5.0 drivers compete regionally and are a consistent podium threat. 5.0 drivers adapt their driving style to take advantage of their opponents’ weaknesses and drive fast in wet conditions or heavy traffic. Lap times are consistent and less than 1 second off the track record for their car. 5.5 drivers are a threat to win every regional race and they may also compete on the national level. They may own a lap record in their favored class.

Level 6-7: Professional. 6.0 drivers are well-known on the national level and are paid to race as a full time occupation. 7.0 drivers have an international reputation and several sponsors with deep pockets.

The ABC System

Smaller tennis tournaments often use an ABC ranking system for Advanced, Intermediate, and Beginner levels. The definitions of those are pretty loose. The A class is generally people who played competitive tennis in college or high school. The C class is for people who have recently begun playing. The B class is everyone in between. In driving, the A class is club racers and above. The C class is people who don’t really know what they’re doing on track. B class contains most of the HPDE & autocross types.

To a very rough approximation, you can figure out what kind of a driver you are based on a very simple question. When you’re cornering on track and your tires begin to slide, what do you do?

  • A. Speed up
  • B. Maintain speed
  • C. Slow down

Spec Percent System (SPS)

One of the most objective ways to gauge your driver skill against others is by comparing lap times in equivalent vehicles and conditions. Differences in weather, opponents, rules, etc. introduce some difficulties both in real life and simulation (where cars and tracks may change as the software is updated). So small differences in rating are not very meaningful and large gaps in calendar time are a warning sign.

Let’s assume the track record is 1:52 (112 sec) and your personal best is 1:57 (117 sec). Your SPS is 112/117 or 95.7%. Another way to think about this is that your average speed is 95.7% of the track record. You can also calculate the percentage in the reciprocal (117/112, 104.4%), which shows how much extra time you have per lap. Regardless, 100% is optimal. Even if you don’t have a Spec Miata, Spec E30, Spec Racer Ford, or some other tightly regulated vehicle, you can still compare your performance to those times as a way of charting your progress over time and from track to track.

Scratch Racing

The concept of par in Golf is unique among sports. It’s the number of strokes a very good golfer is supposed to use for a hole. A scratch golfer is one who averages par for an entire 18 hole course. If we had the concept of par in racing, how fast would a scratch racer be? Of course such a figure is complicated by the specific car and course, but let’s not let minor details get in the way of a little fun.

In golf, handicap is how many strokes over par you would be after a typical 18 hole round. The average score among all golfers is around 100, which equates to a handicap of 28. But the data for non-handicapped golfers isn’t tracked very well, so let’s abandon that for now (it’s sort of like including the lap times of people who don’t have timers). Handicaps are set by the best 10 rounds within the last 20 played. A handicap is therefore not your average round, but the average among your better rounds.

Assuming the distribution of performance in golf and racing are similar, what can we expect from the average racer? As shown in the graphic below (from Golf Digest), the average handicap among male golfers is 14.3. If you’ve ever golfed, you know that it takes a long time to achieve that level of play, and most people never do. So the average handicapped golfer is a pretty good golfer. Similarly, the average racer is a pretty good racer, and most people do not attain that level of skill. Scratch golfers are less than 1% of handicapped golfers but they are still a notch below the professionals. So scratch racers should be similarly the top 1% of all club racers. That equates them with the aliens in iRacing and tennis players with an NTRP ranking of about 5.5 and above.


My rankings

At one time I was a 4.5 tennis player, but irregular court time and age have set me back to 4.0. It took me years to develop a serve I could hit at over 100 mph or kick head-high to the backhand on a second serve. Although my groundstrokes, volleys, and serve could be real weapons, I never developed the consistency to become a 5.0 player. I always entered tournaments in the A class despite not playing on a tennis team in high school or college because I felt that sandbagging in the B class was beneath me. I played enough golf to become a bogey golfer. So, better than the average golfer, but not better than those with handicaps. It’s not saying much.

My RDRS is about 4.0. Every time I go to the track my lap times improve. I heel-toe shift well enough but I haven’t learned left-foot braking at all. I think my main strength is trail-braking, and I’m pretty good in traffic. I don’t have much driving experience on wet tracks though. My lap times generally fall within the same second. In the ABC system, I’m at the bottom of the As. I can’t determine my actual SPS because I don’t have a Spec-anything in real life, but I have tracked my progress against Spec Miatas and have improved from 86% to 94%. In iRacing I’m typically at 98-99% speed and I’m in the fast (under 1:01) category at Lime Rock. My iRating puts me ahead of 75-80% of others, which makes me sort of average among hardcore sim racing enthusiasts.

2 thoughts on “Skill

  1. Where did you get the data for that iRacing histogram? I’d love to be able to pull numbers like that to see how I’m going as I start learning sim racing.


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