Right Foot vs. Left Foot: Part 1

My recent surgery on my right leg meant that I didn’t have the use of my right foot for about 6 weeks. That prompted me to learn how to drive left-footed. I trained on a simulator for several hours and then started driving in the real world. It’s been both fun and educational. While I don’t recommend that anyone snap their Achilles tendon, I do recommend that people get out of their comfort zones.

Now that my left foot is fairly good at driving, it seems a good time to test the age-old question, “how much of an advantage is left foot braking?” Lots of people have asked and answered that. But this is YSAR, so I’m going to go one step further and test something nobody tests: “how good is left foot throttle?” Here are the four combinations.

  • Right foot only (RFO)
  • Right foot throttle, left foot brake (LFB)
  • Left foot only (LFO)
  • Left foot throttle, right foot brake (LFT)

Real World Observations

One of the things I’ve noticed while driving in the real world is that it’s easier for me to drive all righty or all lefty than to mix them. Apparently my brain is wired for one foot even when I drive lefty. While I would love to drive left footed on track, I don’t have a car that can do that. For the time being, I’ll have to test everything in simulation.

Here’s a question for YSAR readers. If you wanted to test left-footed vs. right-footed driving, what car would you use? Here are the criteria:

  • Automatic transmission
  • Ruinable/Cheap
    • I have to drill through the floor to install the left-foot adapter
    • I’d probably want to sell the car later
  • Compatible wheels (4×100 or 5×120 is convenient for the wheels I already own)

Are two feet better than one?

There are two main advantages of using both feet (LFB, LFT).

  1. Less time switching between pedals
  2. You can use both pedals at the same time

It seems obvious that the time it takes to move your foot from one pedal to another represents some kind of loss. I mean, you’re not doing anything during that moment, so it must be a loss, right? Maybe. It’s just a fraction of a second. I don’t think being 0.1 seconds later to changing pedals will result in 0.1 seconds of a lap. But I could be wrong.

The other reason to use both feet is that it allows you to apply brake and throttle at the same time. At first glance, this sounds wasteful if not stupid. But let’s look closer. What happens when you apply brake and throttle at the same time? Since your brakes are more powerful than your engine, it doesn’t necessarily make you brake less effectively. What it does is change your brake balance. Mixing brake and throttle is therefore similar to tweaking a proportioning valve.

Given that you can change your brake bias on the fly, it means you can and maybe should set up your car differently. For example, on a RWD car, you can set up with more rear bias because you can always remove some of that with the throttle. I’m not sure you would do that with FWD though.

In theory, I understand how to use both pedals simultaneously. However, I don’t have a lot of practice. So I’m probably not going to be very good at it, initially. I’ll have to train myself and see what happens.

Upcoming on YSAR

Check back for test results on the various kinds of footwork.

The team is racing at Buttonwillow in a week. I won’t be driving, but I’ll be post a race report and some video.

I started a new blog about my attempt to not suck at billiards.

9 thoughts on “Right Foot vs. Left Foot: Part 1

  1. I would go with ruinable/cheap because I totally suck at braking. I’m doing your drill 3rd gear no brakes and I’m only 0.1/0.2 seconds slower than using 2 or even 3 pedals. It’s really hard to believe that without brakes and using only one gear I’m only tiny fraction of a second slower. Others have at least 1 second difference. I’m doing something seriously wrong, maybe I focus too much on top speed? Compared my data with yours, in some places I have higher speeds than you, but my lap times suck.


      1. On the one hand, the controls are simply throttle, brake, and steering: simple. But I agree, it’s actually pretty complex.


  2. Two thoughts – first, the idea that min speed trumps max speed deserves at least a post all by itself. Second, I find that left foot braking is all but impossible to do quickly in Miatae due to the clutch getting in the way (and a somewhat compromised seating position, because Miata). Any recommendations?


    1. Consider this scenario: Driver A: min speed 70 top speed 165 vs Driver B: min 77 top 158. Difference between min speed is 10% but top is 4%. Driver A/B traveled with min speed for 1 second so driver A will have to travel 2.5 seconds with top speed to cover the loss (or something like this but you get the point). If the straight after the corner is long enough than aiming for top speed may work.


  3. Ian I need to take a brake because I’m overtrained so I won’t be here for few weeks. After 3 or 4 months in which I did few thousand laps at Brands Indy (maybe only 50 laps I was shifting ) here is what I achived:
    Miata no brakes: 1:03.1
    Miata 3rd gear only 1:02.4
    Miata 3 pedals: 1:02.0

    BMW 1M 3rd gear only: 0:54.25 which places me 4th only 0.5 slower than the record holder at http://www.radiators-champ.com/RSRLiveTiming/index.php?page=rank&track=3103&car=64&rank_type=all&tyre_type=all&controller_type=all&community=all&friends=all

    My next goal is to further improve using brake pedal + more consistency (need upgrade g29 pedals). At my current level I find shifting and heel-toe useless so this is the last thing I’m going to learn.

    This is my road to be 1%er. YSAR, Jakub Krcma video driving him Miata on Brands Indy and Ultimate Speed improved my knowledge a lot in a very short period. As a self learner it would take me years to figure it all and cost me a fortune.


    1. Great work. I would definitely upgrade pedals. You should have a load cell on the brake. Not sure the g29 have that. The new Logitech direct drive wheel and load cell pedals look great but they are expensive.

      For your next drills, I suggest driving on dirt. Being tidy and fast is important, but so is messy and fast.


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