JP66

I just finished 5 days of Skippy racing school, 3 at Thompson in the pouring rain in Formula cars and 2 at Lime Rock Park in the MX-5 cars. The fastest 2 drivers at Lime Rock were two teenagers from Columbia that had extensive race experience and are working towards what they hope will be a spot in professional racing someday. I tried very hard to keep up with them and learn from what they were doing, and I am proud to say that on several laps I was able to keep up because I was faster through Big Bend and the Left Hander (Thank you Peter!), but I always lost them on the Up Hiill and the Down Hill. Speaking with them in between sessions I tried to figure out what was making the difference. What was most interesting to me was what they said about the Down Hill. They said they were flat with a left foot brake to "settle" the car. And that reminded me of this quote from Matt:

So, I will definitely make the effort to learn left foot braking, but while I'm developing the muscle memory and before I'm comfortable using it 100% of the time do the wise folks here on Rennlist think it would be foolish to use only on the Downhill at Lime Rock Park?

As always I will ultimately take this up with my coaches, but I'm just curious what folks here think.

Veloce Raptor

I concur with Matt

Frank 993 C4S

Theoretically, you can left foot brake everywhere you have to brake that does not require a downshift, however I do not think the Lime Rock Downhill necessarily requires a brake to settle a car if you time the turn in at the compression correctly (it doesn't in my car but it might in others). Turn 6 at NJMP is a good left foot braking opportunity.

If I had a PDK car, I would left foot brake 100% of the time. Left foot braking is best practiced on your way to the track.

jlanka

So a left foot brake tap instead of a lift? Makes sense to me.

ProCoach

The problem with "the lift" is that its always longer than you think or remember it!

LFB works for many folks. There are an equal number (or greater, IME) of folks who are just fine with RFB. In examining pros and accomplished amateurs over the years, it's not conclusive that one technique is better than the other.

I recommend people become VERY practiced with this IN YOUR STREET CAR and ON PUBLIC ROADS before integrating this technique into their track driving.

Too many drivers exhibit unbalanced (more than 100% applied to BOTH pedals for TOO long) application rather than the "see-saw," rocker approach between the two pedals. VErY apparent on the data...

Is LFB quicker in the Downhill? For Matt, it is.

For me? I don't have to modulate or brake at all!

Be careful, Joe. There are no "silver bullets" in this game...

JP66

As always sage words of advice from you guys!

Peter,

You know how I am constantly overthinking stuff, and I'm sure this is another example

It all boils down to wanting to achieve the best possible laps at Lime Rock when I start driving my SP2 car. As it is definitely a "momentum" car as is the MX-5 I am trying to figure out where I may find the most room for improvement. Following behind the "pro-racers" was enlightening. I feel strongly that the lesson with you gave me a tremendous level of confidence in Big Bend and the Left Hander as was proven when I overtook the "pros" in that corner, but every time I fell in behind them on the Down Hill, their subsequent run on the straight away was much faster and I was using a lift and a tiny brush of brake. I wish I had data to compare to know what is really going on, but the whole gist of what I'm "over thinking" at the moment is if I can get away with using that technique only on that corner and only at Lime Rock Park for the moment.


I find it very interesting that your experience says that overall drivers who use left foot braking are not inherently faster, and I think that speaks perfectly to what I am now thinking.

Rather than learn and use left foot braking all the time, can one safely employ the technique in situations where it is a proven benefit, and furthermore is that really the reason the Columbian teenagers were pulling away from me or was there more involved???

ProCoach

Yes, one can safely and in a very targeted way, use this technique to aid in lowering sector times (which is how you would objectively validate your execution of it).

No, that is not THE reason, but it may be one of the ingredients!

Thundermoose

I can't comment on LRP but in the progression of what's faster it's almost always in this order:
Flat > lift > LFB > RFB. If you have to brake, the try to LFB. If you can get away with a lift then lift. But look at data. As Peter states you'll almost always lift longer than you think initially and negate any gains. However you should always be working your way to the left (of my equation) until you reach limits of grips. I am sure there are exceptions but I think what I've stated is true more often than not.

I know sims seem to like braking more than lifting FWIW.

Frank 993 C4S

Brake and Throttle at the same time only works effectively on cars without brake/throttle interlock. On all modern Porsches you need to flash the ECU to achieve that. Not sure about SPB.

Thundermoose

Wouldn't brake override throttle ? That would seem safer.

Frank 993 C4S

With the brake/throttle interlock, the ECU abruptly cuts fuel when you apply brake and throttle at the same time. Try it sometime - it's quite dramatic, like hitting the rev limiter and NOT what you want when your car is at the limit of traction. You might be able to get away with a slight tap but that's tough to modulate with your left foot.

jlanka

I'll have to try it at Summit

Aspen Autosports

The modern Porsche does cut the throttle when applying the brake at the same time, as do other cars of various manufacturers with e-throttle. However if you apply the brake then apply the throttle it does not cut. So in a modern Porsche in order to effectively left foot brake you must follow this sequence of events: throttle, lift, left foot brake, throttle. As Frank says you can flash the ECU to eliminate that "feature". The SPB does not suffer from this as it is the good old fashion cable throttle.

Veloce Raptor

Actually you get about 2/3 of a second before it cuts throttle

mmuller

The reason it was better for me in the SPB is that in an SPB, which has a very lively rear end at the limit, you end up sawing the steering wheel so aggressively at exit that you scrub speed. Data showed it was faster at apex but by the time you where at trackout it was 2mph slower, which resulted in a 5mph difference at the end of the straight.

When you add the left foot brake it settles the car without taking to much speed out.