Why Smooth Is Fast?

[FTS]

By Ross Bentley:

[RingMeister01]

I love his books. I have them all.

[MaynardZed]

"Smooth is Fast" is definitely a concept I'm familiar with from my days of competing in Strongman. You want to be smooth when running with an 800lb yoke on your back. Different sport, same concept.

[M4TW]

I agree with the goal. Any tips or tricks that you (or any of the other pros) care to share about how to achieve it - or things we might be doing wrong that are keeping us from it?

[consolidated]

Ross Bentley has a weekly speed secrets email subscription worth a few bucks.

[M4TW]

Originally Posted by consolidated

Ross Bentley has a weekly speed secrets email subscription worth a few bucks.

Subscribed.

[FTS]

Originally Posted by M4TW

I agree with the goal. Any tips or tricks that you (or any of the other pros) care to share about how to achieve it - or things we might be doing wrong that are keeping us from it?

As you can imagine this is not a simple question that has a simple answer; however, there are few thing to keep in mind: The way you minimize weight transfer is through minimizing steering input, progressive brake application and release, and same for throttle.

Obviously that sounds quite ridiculous when you are approaching a 40-mph corner at high speed (say at 150 mph), you have to slow down fast and have to turn hard to make the corner, then you have to accelerate hard and you smash the throttle. When you go through this sequence you are most likely slow, because it is not the smooth way of doing it.

When you are approaching such a corner, first you don't slam the brakes, but gradually increase brake pressure to maximum and gradually release the brakes. You may then put, for a moment, a large steering angle at the beginning of the corner (depends on several factors) and almost immediately straighten it leaving a very small angle, while rolling off the brakes and onto the throttle (squeezing the pedal) and manage the cars angle and attitude through more with the throttle than steering (I am not talking drifting here).

I am not sure if the above makes any sense, but there are couple of things to also keep in mind:

• Smooth does not mean slow hand or feet movement; this is the primary mistake I see in novice drivers that try to be smooth. The coordination of the hands and feet need to result in smooth transitions in the car's attitude
• Techniques differ greatly between slow- vs. high-speed corners, don't treat them the same and try to apply same approach

A lot of this comes with seat time and techniques also different from car to car, for example an M3 (front-engine rear-drive with 52/48% static weight distribution) vs. a 911 (rear-engine, rear-drive, 37/63% static weight distribution); their dynamic weight distribution cannot be any more different, so you need to take advantage of the configuration while practicing smoothness

One last point; 'seat time' does not mean anything and it is a waste of time if one does not have baselines and works towards well-defined improvement goals, otherwise you are just turning around in circles. So, I always recommend that drivers have some way of collecting data, look at it at every opportunity to understand what the difference are between what they think they are doing vs. what they are actually doing, then define new goals and techniques. Continue rinse cycle

[robbo mcs]

Originally Posted by M4TW

I agree with the goal. Any tips or tricks that you (or any of the other pros) care to share about how to achieve it - or things we might be doing wrong that are keeping us from it?

Race in the wet as much as you can!

I see so many people who get annoyed when it rains at the track. Some people at club level don't even turn up if it is wet, or pack up and go home early.

I understand the frustrations, it is slow, it is hard to benchmark times etc.

However, when it is wet embrace it and use it as an opportunity to learn. It doesn't matter what tires you are on. In the wet you have to be smooth in transitions. It forces you to be smooth, and punishes you if you are not.

[M4TW]

Originally Posted by FTS

As you can imagine this is not a simple question that has a simple answer; however, there are few thing to keep in mind: The way you minimize weight transfer is through minimizing steering input, progressive brake application and release, and same for throttle.

Obviously that sounds quite ridiculous when you are approaching a 40-mph corner at high speed (say at 150 mph), you have to slow down fast and have to turn hard to make the corner, then you have to accelerate hard and you smash the throttle. When you go through this sequence you are most likely slow, because it is not the smooth way of doing it.

When you are approaching such a corner, first you don't slam the brakes, but gradually increase brake pressure to maximum and gradually release the brakes. You may then put, for a moment, a large steering angle at the beginning of the corner (depends on several factors) and almost immediately straighten it leaving a very small angle, while rolling off the brakes and onto the throttle (squeezing the pedal) and manage the cars angle and attitude through more with the throttle than steering (I am not talking drifting here).

I am not sure if the above makes any sense, but there are couple of things to also keep in mind:

• Smooth does not mean slow hand or feet movement; this is the primary mistake I see in novice drivers that try to be smooth. The coordination of the hands and feet need to result in smooth transitions in the car's attitude
• Techniques differ greatly between slow- vs. high-speed corners, don't treat them the same and try to apply same approach

A lot of this comes with seat time and techniques also different from car to car, for example an M3 (front-engine rear-drive with 52/48% static weight distribution) vs. a 911 (rear-engine, rear-drive, 37/63% static weight distribution); their dynamic weight distribution cannot be any more different, so you need to take advantage of the configuration while practicing smoothness

One last point; 'seat time' does not mean anything and it is a waste of time if one does not have baselines and works towards well-defined improvement goals, otherwise you are just turning around in circles. So, I always recommend that drivers have some way of collecting data, look at it at every opportunity to understand what the difference are between what they think they are doing vs. what they are actually doing, then define new goals and techniques. Continue rinse cycle

Thanks for taking the time to write that. Transitioning from theory to body memory is obviously the rub, but I am finding that some of the techniques are counter-intuitive to learned (bad) habits and require deliberate overrides to correct. That's why I am trying to soak up as much as I can.

A couple of questions.

Can you please distinguish between the bad habit of "taking multiple stabs at a corner" and what you describe at the initial turn-in of using (where warranted) a large steering angle at the beginning of a corner? I think I know the answer, but there is a difference between knowing and guessing.

Secondly, In trying to be a good pilot of my M4 buggy I'd like to know what areas you would consider to be its strengths (areas that would allow me to push my comfort zone ) and weaknesses (where I should ease off)? I guess this may have to wait until after you take delivery (I am certainly looking forward to your impressions!).

Originally Posted by robbo mcs

Race in the wet as much as you can!

I see so many people who get annoyed when it rains at the track. Some people at club level don't even turn up if it is wet, or pack up and go home early.

I understand the frustrations, it is slow, it is hard to benchmark times etc.

However, when it is wet embrace it and use it as an opportunity to learn. It doesn't matter what tires you are on. In the wet you have to be smooth in transitions. It forces you to be smooth, and punishes you if you are not.

Ha ha. On my first and only outing most of my sessions were in the wet. My instructor said it made me a much better driver because it forced me to slow down.

[MaynardZed]

Originally Posted by FTS

When you are approaching such a corner, first you don't slam the brakes, but gradually increase brake pressure to maximum and gradually release the brakes. You may then put, for a moment, a large steering angle at the beginning of the corner (depends on several factors) and almost immediately straighten it leaving a very small angle, while rolling off the brakes and onto the throttle (squeezing the pedal) and manage the cars angle and attitude through more with the throttle than steering (I am not talking drifting here).

I understand all this except for the first sentence regarding slowing down from high speed (assuming you mean from a straight?). I was taught that on a straight you should be either 100% on the throttle or 100% on the brakes. The timing of the switchover from throttle to brake is of course key, but since you are going straight the tire is stressed in only 1 vector so its OK to sort of "mash" the brakes with some sensibility about it.

Other than that I understand you're describing a slow in / fast out corner and "steering with the rear" of the car?

[consolidated]

Originally Posted by MaynardZed

I understand all this except for the first sentence regarding slowing down from high speed (assuming you mean from a straight?). I was taught that on a straight you should be either 100% on the throttle or 100% on the brakes. The timing of the switchover from throttle to brake is of course key, but since you are going straight the tire is stressed in only 1 vector so its OK to sort of "mash" the brakes with some sensibility about it.

Other than that I understand you're describing a slow in / fast out corner and "steering with the rear" of the car?

How quick you can go to threshold braking depends on the set-up and stiffness of the suspension, soft and long travel takes slightly more time to transfer weight up front and stay out of lock-up or ABS.

But yeah, if you look at the braking data (g and pedal pressure) trace of a good driver in a track sprung car it gets steep very very quickly.

[FTS]

Originally Posted by M4TW

Can you please distinguish between the bad habit of "taking multiple stabs at a corner" and what you describe at the initial turn-in of using (where warranted) a large steering angle at the beginning of a corner? I think I know the answer, but there is a difference between knowing and guessing.

There is an unconventional technique, and quite counter-intuitive, which I found the Cup car drivers tend to use often, I am trying to learn it as well. When approaching a corner faster than the tires would allow you to take, you can put a very high steering angle (almost like putting your skis into 90 deg angle to scrub speed but not turn) at the entry to scrub the speed (intentional terminal understeer). However to stabilize the attitude of the car, have the chassis stay within maximum traction, you are off the brakes and on the throttle. This way the car is slowing down, but you are also keeping the weight from overwhelming the front axle. Once the car is at the appropriate speed, you take away the steering angle and increase the throttle and the car hopefully shoots out of the corner like a bat out of hell. Getting the timing of all the controls is mighty difficult as I am finding, when it works it is great. This is quite an abuse on front tires, but with the 911s, you don't worry too much about that

Originally Posted by M4TW

Secondly, In trying to be a good pilot of my M4 buggy I'd like to know what areas you would consider to be its strengths (areas that would allow me to push my comfort zone ) and weaknesses (where I should ease off)? I guess this may have to wait until after you take delivery (I am certainly looking forward to your impressions!).

I wish I knew, I really don't at this time. The biggest disadvantage is the dynamic weight distribution in and out of corners; I am comparing to the 911. However, its biggest advantage maybe mid-corner due to weight distribution again. At the same time, I am hoping that the front-heaviness may be an advantage under braking, if it does not overwhelm the tires, so bigger tires we can fit in front, I think it will be better, but I am guessing.

The other advantage I hope will be the trick differential. With this diff, the car should not understeer in corner entry, and should be able to put a lot of the power down on exit. Again to be able to take advantage of this I think we will need as big tires as we can fit on the rears, I am hopeful of 325s, but we'll see.

I am really looking forward to going through the journey of finding all these answers over the coming years, it is like an expedition for me

Originally Posted by MaynardZed

I understand all this except for the first sentence regarding slowing down from high speed (assuming you mean from a straight?). I was taught that on a straight you should be either 100% on the throttle or 100% on the brakes. The timing of the switchover from throttle to brake is of course key, but since you are going straight the tire is stressed in only 1 vector so its OK to sort of "mash" the brakes with some sensibility about it.

Other than that I understand you're describing a slow in / fast out corner and "steering with the rear" of the car?

@Consolidated has a great point.

First, I think we can dedicate several pages to what 'slow in/fast out' means, but for me it means late apexing, which I try to avoid as best as I can. I subscribe to the idea of 'fast in/fast out'.

You are right, we have been taught since childhood that on a straight line we should get to maximum braking force as quickly as we can. However, I find that it just does not work with street cars, it works great with GT3 Cup cars, but those have 1200# front and 1400# rear spring, either lack ABS or have motorsports ABS and DSC.

When you slam on the brakes on a street car on a straight line, the weight transfer out of the rear axle is so significant that ABS/DSC systems get confused to the level of becoming dangerous (a.k.a. Ice Pedal, see lecture vid here). Additionally, street cars' suspension components are designed for street tires and at best we get to use r-comps, but they don't do well at all with racing slicks.

I had a lot of issues in learning how to brake frankly, so I collected a lot of data, and I think I am starting to understand how to best brake with street based cars. The progressive braking results in smoother transition of the weight, hence better grip and does yield shorter distances and more stable braking. However, it is important to note that when I say progressive, the difference in time using this technique to get to threshold vs. slamming to get to threshold is less than 0.2-0.3 secs. In absolute times, it seems inconsequential, but when going 120-150 mph that is very significant.

I hope this makes some sense. If you don't mind getting bored reading data stuff, you can see some of the data I collected and my conclusions over here.

[M4TW]

I think I'm going to have to take your word for it on the above described cornering technique. At least for now. The braking one, however, I get. I'm getting the impression that learning good track technique is akin to walking with a book balanced on your head - only it's more like balancing while running very fast, with hard braking, acceleration and sharp turns. :-)

I'm enjoying this, so I want to try and keep it going. What are the top 3 noob mistakes in your experience and how are they best corrected? Where do us rookies typically make our biggest gains?

Great blog btw. I'm glad you've made your way back into the seat of an ///M. I hope it does not disappoint. I also liked the CCB section - having tried to defend them mostly unarmed. The link is here if anyone else is interested in the blog.

http://drivingsatisfaction.blogspot.ca/?m=1

[MaynardZed]

Great write up FTS. The first section was funny too talking about the typical macho stuff you see at the track.

[FTS]

Originally Posted by M4TW

I'm enjoying this, so I want to try and keep it going. What are the top 3 noob mistakes in your experience and how are they best corrected? Where do us rookies typically make our biggest gains?

Good questions frankly. In my circles I'd say my top 3 would be:

• Looking 20-30 ft ahead of the car, fixating to near objects (like other cars), and not looking far ahead particularly through corners
• Being too abrupt with the controls; sharp steering movements, aggressive throttle applications, and sudden release of brakes
• Forgetting to breath; sounds silly may be but it is amazing how much calmer drivers become when they actually learn to breath normally even through stressful times

The biggest gains I have observed comes from fixing the first one above. Once drivers learn to look far enough ahead, their inputs become proportionally smoother by nature, and they also start breathing better, become calmer and suddenly all things start to click. Once this phase is reached, they are truly ready to learn

Originally Posted by M4TW

Great blog btw.

Originally Posted by MaynardZed

Great write up FTS. The first section was funny too talking about the typical macho stuff you see at the track.

Thank you for reading I am not a good writer, but writing helps with the waiting

I have three more parts to edit and post on the data stuff, but its stiff and not so entertaining. It is more about keeping my own notes for next season classroom sessions.

[Gearhead999s]

Some more thoughts on techniques.

http://jalopnik.com/5937814/why-the-...ique-is-a-myth

[FTS]

Originally Posted by Gearhead999s

Some more thoughts on techniques.

http://jalopnik.com/5937814/why-the-...ique-is-a-myth

I was not aware of this article, but it so eloquently describes fast-in/fast-out and it being written by a pro racer is the icing on the cake.

The fundamental piece of fast-in/fast-out is early turn in, the advantages are immense. It is about putting very slight steering angle early on while carrying the speed and letting the car drift on four wheels, within slip angles, and staying on the power. This works for high speed corners.

For slow speed corners, you still put slight steering angle early on and manage the attitude of the car with the brakes, but it is almost never threshold braking. Some people mistake this with trail-braking, but I found out that most pro drivers don't like that terminology at all. Trail-braking to them implies slowing down using the brakes; whereas managing the attitude of the car with the brakes with minimal momentum loss is something else, but I have not yet come across a proper term that would describe it and is commonly accepted. So, I just call it early turn-in and fast-in/fast-out.

So along the lines of the previous question, what would be your top 3 mistakes experiences driver tend to make? My list would be:

• Late turn-ins
• Initial brake application and release
• Not analyzing data

[Gearhead999s]

Another point is reminding students of the following

slow corners = fast hands

fast corners = slow hands

[FTS]

Originally Posted by Gearhead999s

Another point is reminding students of the following

slow corners = fast hands

fast corners = slow hands

[M4isKing]

fastest lap smooth

2nd fastest lap (lost some time because not smooth in one section, but then gave up on the test of the lap so im curious what the difference would have been)

rest of video - bunch of not so smooth moments!!

no love from e92 section but fits this smooth/not smooth discussion. (there are more replies to exhaust sound vids than an actual trackday vid!!!)

[FTS]

@M4isKing, I do not know this track at all, it is tough for me to comment intelligently; however, it did look mostly quite smooth to me. It may be just the angle of the video, but during the first set of essess your hands looked a little slow for the speed, but the second set seemed quite good.

Also, that was a very good save I think, well done. I think as soon as the backend started coming around, you seemed to have lifted and the angle increased very rapidly, thankfully you stayed ahead of that rotation.

Nice driving

[MaynardZed]

Enjoyed the video and commentary. The exhaust on your M4 sounds great!

Assume that was a point-by only passing group? Those Miatas can get annoying. That was a tricky section where you're turning while your weight is unsprung. Good to see you were trying different approaches to that turn but still keeping your speed up. That last spin was predictable, though, since you were off line a bit passing that Miata (probably a little annoyed too). Thanks for posting.

What tires were you running?