SWK6Cup

I am very interested to hear the collective thoughts, especially from Peter and Dave, for example, regarding the technique of "coasting." I read about this in the recent edition of Automobile magazine, in an article describing the Ferrari Corsa Piloti course and the 488 at Mont Trembant (a fantastic track!)

I was always under the (mistaken?) impression that it was either on the brake or on the gas, with much discussion among my track friends and coaches about "patience" and getting back on the gas sooner. I have been told that the "patience" instruction (from Peter Argesinger and Simon Kirkby, for example) are somewhat 911 specific, as the idea is to keep maximum grip on the front end and permit the car to rotate before getting back on the throttle and shifting the weight transfer to the rear.

In the article, the "coasting" theory keeps the front tires loaded, maintaining a proper balance and permitting the pilot to get on the gas sooner, at or before apex(?) providing higher exit speeds........Is this Ferrari (mid engine) specific? (Cayman and Boxster, too?)

Veloce Raptor

It's not 911 specific

AdamBrouillard

There are times when you wouldn't want to be on the gas or brake, but not for the reasons it sounds like that article is discussing. Cars will still decelerate somewhat while "coasting" from engine braking and drag forces so you might be "coasting" for a significant amount of time during a decreasing radius double apex. You also might coast the last little bit before the apex of a standard corner to lose the last few mph before going to throttle. This will be more noticeable in a corner with lots of direction change like a hairpin.

dizzy8085

You can test this out in iracing. It definitely can be faster. Sometimes. Haha.

Veloce Raptor

It's less coasting and more of a slight pause before throttle

ProCoach

God, I hate that word "coasting..." And I have not read the article.

YOU HAVE TO GET THE CAR TURNING FIRST, THEN you can "coast..."

I think Adam is too loosey-goosey in his observations, but generally agree with his last sentence. I believe David nails it pretty well with his last observation posted.

To me, "coasting" (and I think of Ross Bentley, Seth Thomas, Tom Long, Argy and Simon's protracted discussions with me on this very question) MUST entail a rotational or "yaw moment" that coordinates perfectly with the period of "no pedal" (a great and better description of this phenomena by the fantastic SBRS instructor and race winner, Barry Waddell). I have an article on this in my "Track Wisdom" section of my website explaining my application of his advice back in 2008 when he coached me on a track I know well on iRacing in beta testing.

So yes, as you get quicker, there is a period where the proper approach speed (EoB and past enough to have the car HEADING be correct) promulgates and makes easy this yaw moment (better known as "rotation") period. And this is definitely platform-independent...

At this speed, and with the car in a relatively unstable state (rotating at a controllable yaw rate, on or near it's Cg, which is forward of the engine/trans in traditional 911's, and even more so in 458/488's), and with the gSum high, carried through unabated from peak deceleration and blending into max lateral loading, it IS acceptable to have no brake or throttle application.

Remember, for me, the definition of the limit WOULD BE where the SMALLEST change in either of those control inputs (OR steering) MAKES a difference, AT the limit.

Cool subject. I used to be a dyed in wool Bertil Roos approach (either of the pedals, ALL the time) devotee... But in analyzing what the best drivers do, it was clear there was room to grow WITHOUT necessarily following that simplistic advice...

Dr911

Peter’s explanation makes the most sense to me.

“Coasting” I think of as a pejorative term applied to easing off throttle too soon before the braking zone.

It’s inaccurate imo to apply it to describe what is essentially “throttle modulation” .... which is (in my view) the natural next transition point at the end of trail braking and is the precursor to exit throttle.

My 2c.

ProCoach

Absolutely agree with your read of "coasting" as a pejorative (read: undesirable state) term.

Again, IF the entry speed is sufficiently high, and the release of brakes sufficiently deep, enough to induce this yaw moment, the car CANNOT accept any more brake or any additional throttle application. THIS is what Seth, Tom, Argetsinger and Simon were talking about when THEY reference "coasting."

Throttle modulation before the apex (and for sure AFTER the apex) means you overslowed (and early, to boot) and you have to get on down the road to the point where you are better pointed in the direction you want to go BEFORE you can get back on corner exit progression to WOT...

This stuff is HARD! <grin>

sbelles

Once in a while, even in a no hp car, you are just along for the ride, waiting for previous inputs to play out. The trick is knowing when the ride is over.

ProCoach

Hahaha! FanTAStic! I'll have to steal that. Too funny. And true...

I think this is one of the reasons why it's SO much easier to DO this in a no hp car. The speed differentials (vMax to end of braking, and beyond) are such that the driver has FAR more time to read and process...

Matt Romanowski

I'll try and post up some data from these exact sequences. I posted a thread in the data forum about the car continuing to slow with no brake or throttle, just steering. This is the sort of coasting that we're talking about here. IMHO, you have to think about slowing in stages. The first large, rapid hit of the brakes takes away the most speed, then the pedal pressure is slowly release and the fine tuning starts. When you do it just right, then the last part of the slowing is done with just steering input and no pedal (brake or throttle) input. As you start to pick up throttle, you reverse the sequence with your acceleration. You can see this in a speed graph very quickly.

Now, there is other coasting that people do between throttle and brake inputs at the end of straights. This is almost always bad for speed, but can be good for mileage and other things. I just read an article about Formula E racing where they are using that sort of coasting to manage battery regeneration. Very interesting stuff!

Ed@Demonspeed

Call it being slow to transition from trail braking to modulating on the throttle.

Peter, you make an interesting statement. When and where in the corner do you expect throttle modulation and where would you expect opening to full throttle. Are you saying that if there is an opportunity to go back to the throttle before the apex, then your entry (or trail braking) as left you too slow.

Thanks

Ed

ProCoach

That's even better (in bold).

Ed, that's difficult to answer as one size does not fit all, but the best drivers I've worked with CAN'T go to throttle (as the yaw rate of change is going on) and they often DO go to modulated throttle AS THE CAR REACHES the proper heading to PRESERVE the most desirable slip angle (or yaw), THEN go on to progress to WOT.

The point at which they do this depends on the length of radius and travel, topography and consistency of radius around the corner. If you look at the GT cars in the top levels, the period of the greatest yaw is somewhere AFTER turn-in (due to brakes trailed in) and closer to the approach (last few car lengths before) or at the apex (the slower the corner, the later the yaw moment).

I do NOT subscribe to the idea that IF a driver is able to go back to SOME power before the apex, that there is untapped gSum potential, as some confident drivers in a well-balanced car DO go back to power to SUSTAIN the proper slip angle and achieve an earlier "exit heading lock." But the yaw rate-of-change HAS to come first. And that is often accompanied with a "no pedal" condition.

For sure, IF THE NOSE COMES UP before the yaw rate of change occurs (which would come from releasing brakes TOO soon, or by going back to power BEFORE the car points into the corner), THAT would be a problem.

Here's one of my favorite videos. Matt is on the throttle ever so slightly to stabilize the car through T9 and T10, but good patience and clockwork precision at the slowest corners like T11. A handful, for sure.

Veloce Raptor

Go on YouTube and look for Cory Friedman's videos. Pay close attention to when he comes off brake and when he goes to gas. There is a short pause...which allows him to fully commit to throttle ONCE

fatbillybob

To me that's what might make a miata easier to drive than a ZR1 corvette. Having never driven a miata people always say to cut your teeth there yet IMO miata driving does nothing for being fast in a high HP car where that DeltaV is huge. But what do I know I'm a slow clubracer...