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Hi guys,

I'm signing up for some classes this year since I desperately need them. I know I'm only getting about 50% our of my RS4 because of my inabilities. And I want to make sure that when I get my Elise, I can enjoy it to it's fullest as well - and safely! I'm a pretty good driver, I think, but I'd likely be dead on a racetrack in about 3 seconds. Plus, I honestly think that knowing better racing techniques can be applied to the road for safer driving and a better understanding of how and what to do if you lose control, and how to avoid it.

So I have a three part question.

1) When, exactly, do you do the heel and toe downshift? Is the downshift completed BEFORE you enter the turn or as you hit the Apex?
2) Do most of you double-clutch downshift or just single clutch and let synchromesh do it's job?
3) Do most cars (specifically the Elise) come standard with the pedals pretty much set up for heel and toe shifting? Or do you guys jod the car to make it easier? I've seen a million mods but none mention adjusting the pedals, so I'm assuming the car is pretty easy to heel and toe as is.

Also, and sort of unreleated- which classes do you guys recommend? Barber? Lotus (in Vegas)? Porsche driving school? Areal Atom experience? Etc...

I'm planning on way more then 1 class, but I'd like an order so I don't go to one that is really more for advanced drivers first...

FInally, does anyone suggest a good source for me to read about and understand driving theory so I'm sort of versed on the classroom stuff before I go?

Thanks.

-Matt :nanner2:
 

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1) When, exactly, do you do the heel and toe downshift? Is the downshift completed BEFORE you enter the turn or as you hit the Apex?

Before the turn-in point, usually. Note that you can still be braking as you turn in, but usually you'd want to get the downshifts done by then.

2) Do most of you double-clutch downshift or just single clutch and let synchromesh do it's job?

I tend to single clutch.

3) Do most cars (specifically the Elise) come standard with the pedals pretty much set up for heel and toe shifting? Or do you guys jod the car to make it easier? I've seen a million mods but none mention adjusting the pedals, so I'm assuming the car is pretty easy to heel and toe as is.

The 05 pedals seem a little tougher to Heel-Toe. I found the 06+ pedals fine. My 07 is fine.

Cheers,
-Darryl
 

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Hi guys,

1) When, exactly, do you do the heel and toe downshift? Is the downshift completed BEFORE you enter the turn or as you hit the Apex?
Always have the gear changes done before any steering inputs, so do it in a straight line. Last thing you want to do is miss the shift midcorner and screw the balance of the car up and possibly spin.

2) Do most of you double-clutch downshift or just single clutch and let synchromesh do it's job?Both. I tend to single clutch the higher gears, and double clutch the lower gears. No matter what car, I always double clutch into first, but you will rarely come across a 1st gear turn on the track. For teh street, it's handy though

3) Do most cars (specifically the Elise) come standard with the pedals pretty much set up for heel and toe shifting? Or do you guys jod the car to make it easier? I've seen a million mods but none mention adjusting the pedals, so I'm assuming the car is pretty easy to heel and toe as is.
I never really had an issue with the '05s, and the later Elises/Exiges have been cake to heel and toe. That does depend on your foot though, and how you actually heel and toe. Different sized feet cause different issues, and my 10.5's are seem to be in the sweet spot for most cars.
Answers in bold for you Matt. BTW, I liked Barber.
 

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Check out some of the HPDE threads and for stuff in the area. I haven't tracked my car yet, but plan on soon. I'm gonna start signing up for some of the beginner HPDE sessions at Lime Rock and Pocono Raceway with the different organizations. Try reading up on some of it in other threads and maybe I'll see you at some events.
 

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for those of you that are a bit more analytical...

The topic of shifting an Elise comes up occasionally and so I decided to write a page on the subject. It is a bit more analytical with some animations on shift lever movement and synchromesh. There is even a parts diagram of the gear box.

Lotus Elise Experience, How to Shift Gears

Comments gratefully accepted.

Me, I shift before the turn as I do not want to unsettle the rear tires while I am braking. Letting out the clutch in the turn will use some of your friction circle laterally and I want it focused on turning.

I am an old fart and so I double clutch. Modern gearboxes do not need it and I am trying to learn to just blip the throttle while traversing the neutral spot, as was taught at Jim Russell driving school.

Michael
 

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Always get your shifting done before turn-in. If you're an advanced driver with a keen sense of weight transfer and good talent for car control, it's sometimes OK to still be braking during turn-in (i.e, trailbraking), but you always want to get your heel-toe downshift complete before turn-in.

I recommend Skip Barber. In fact, I now would recommend their MX5 Cup courses over their open-wheel courses. I have done five days in their open wheel cars, but have also been coached by Barber instructors in my car, and I think a relative newbie could get much more out of the experience of having an instructor in the passenger seat. (Though there is no denying that the open-wheel cars are incredibly fun!)

Matt, send me a PM with your mailing address and I'll send you a copy of the following magazine: High Performance Driving.

-Jon
 

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... I am an old fart and so I double clutch. Modern gearboxes do not need it and I am trying to learn to just blip the throttle while traversing the neutral spot, as was taught at Jim Russell driving school.

Michael
I am 46, so I guess I can be considered an old fart as well. I also double clutch. I find I can make much smoother shifts this way. If I try to single clutch I sometimes have a very tough time with the 3-2 downshift in the Elise.
I get all my shifting done while in a straight line, then trail brake (if needed).
 

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If you are a beginner, focus on driving the line and then worry about being in the right gear later. I've seen more people blow shifts, or just flat out drive off the track, worrying about shifting than I can count at HPDEs.

Once you are really comfortable and natural with driving the car, then work on downshifting under braking and getting the car into the ideal rpm band for the exit. :)

But being in the right rpm range is never more important than having the car where it is supposed to be.

And, you should always be hell-and-toe on your downshifts, period, on the street, track, or otherwise. There's no excuse to not be downshifting as as smoothly as possible at all times :)

Steve
 

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I'll just add that before I progressed to heel-toe, I first worked on rev-matching (i.e., heel-toe with out the braking involved). Once rev-matching my downshifts became absolutely unconscious and second-nature, I added actual heel-toe braking/blipping, and it came quite easily.
 

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I went from an RS4 to an Exige and heel-toeing in the Lotus is a breeze compared to the RS4 - the petal box in the RS4 is just not made for heel-toeing. Also remember that you won't have Audi's stability control keeping you out of trouble - you WILL spin your Lotus if you treat turns like you did with the Audi. With the Audi's stability control you can hammer the throttle in a turn and the computer keeps you out of trouble - not so in the Lotus.
-john.
 

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Discussion Starter #12
Thanks!

Thanks everyone. I got even more then I asked for, all useful.

And John, your posting made me feel MUCH better! I also have an RS-4 (as I think you knew) and I just couldn't get the heel-toe thing down. The pedals just don't let me do it. To blip the throttle meant I had to compress the brake WAY more then I needed to slow the car. It just wasn't working. And the point about Audi's stability control is very well taken. I drive the RS-4 pretty damn hard and pummel the throttle on turns. It just loves it and gives back thrills and smiles! I'll be careful when I transition. It'l be hard to constantly change my driving technique since I'm keeping my RS-4 and will be using my RS-4 as a bad weather and kid transporter while I use my (not yet owned) Elise for a good weather commuter and all around fun car.

I'm looking forward to eventually getting the Elise so I can start honing my driving skills a bit more. I may never even go to auto-X but I just want to learn to be a better driver. To enjoy driving more and be safer. Maybe once I get some more free time I'll do the auto-X thing.

I put over 27K a year on my car so I'm on the road a LOT. I look forward to the drive from place to place and it makes the miles my favorite part of the day.


I guess since Toe-Heel is not really possible on my Audi, I'll focus on getting my RPM's to the right # to transition a smoother downshift. I've been sort of working on that already by blipping the throttle just after breaking but before I release the clutch. It just seams to always take too long to perform in such a short time period; so I've sort of accepted the slight lurch during downshift when I come into a turn as acceptable...

Thanks again, and keep the pointers coming!!!

PS - Is there such a thing as private driving lessons in the instructors car to learn better driving skills (auto-X and racing skills, etc.) that might be available by someone in NJ? Obviously my car is NOT a good car to learn on!

-Matt
 

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Me too

I'll just add that before I progressed to heel-toe, I first worked on rev-matching (i.e., heel-toe with out the braking involved). Once rev-matching my downshifts became absolutely unconscious and second-nature, I added actual heel-toe braking/blipping, and it came quite easily.
I forced myself to revmatch NO CLUTCH :eek: untill I had it down, braking came natural after perfecting this
 

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Mattnshilp,

While I've never driven a RS-4, my Audi TT is much easier to rev match on. Seems like most audis have a very slow engine response. What I mean is if you blip the throttle, the RPM go up real fast, but then come down real slow. This gives you alot of time to let the clutch out at the right spot. In the elise, the RPM will go up real fast and drop just as fast. This means you can't have any delay in your clutch work. B/c I drove my audi for 3 years before going to the elise (and not driving any other manual daily) I got accustomed to the delay in RPM drop. I felt like an idiot with the dealer when I went to go drive on my test drive with the elise. Same with moving from a stop, if you like to blip the throttle a little before going forward and releasing the clutch. It happens alot quicker in the elise, as it should with most sports cars. Audi are the only cars I've driven where I've noticed this. It always takes me a few mins to accustom to each car as I switch over and drive them.
 

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Go to Skippy School it has taught the most SCCA drivers around and they good instructors for what you need. I never attended Skippy, Iwent to Winfield in France and it was considered the best followed up by 10 years in FF1600. Braking and shifting are based on set-up of the car, track conditions but most schools will teach brake and downshift in a straight line before the turn in when you start to go to the gas.Winfield taught trail braking for some turns. If yo watch the F1 races you will hear the term rotation or rotating the car. This based on the front end grip which changes the braking. You will find most braking or alot of braking in F1 GP2 and F3 cars is while turning. It seems to come from the guys today coming up from go carts. But you dn't brake while turning on a oval track. Mansell, Prost and others brake while turning. Senna braked mainly before turning. It is what ever wayyou can get the most speed out of the car. Smoothness and not over driving the car is what gets you speed.
 

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btw, as far as pedal locations, I hadn't thought of that. In my Spec Racer it's very tough for me to get proper foot rotation unless I am really on the brakes. During 9/10ths+ driving it's brilliant because when you are on the brakes, you are ON THE BRAKES :) but I remember my very first time out before I truly appreciated the braking forces I could apply I was having issues with "the brake pedal being too high."

Steve
 

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Hope this helps.....................................................................................................................................................................................................Now, if you have driven old cars, or trucks, or sports or racing cars, you will be amused at this play on words. That's because double-clutching is also a procedure to save wear and tear on your gearbox, and on your clutch, at the expense of a little extra work for your left leg. What exactly is double-clutching (or, as the British call it, "double de-clutching"), and why is it significant?


Let's say you're accelerating in second gear. When you're ready to shift into third, you decide not to use the standard approach, which is just to tromp on the clutch, take your foot off the gas, shove the shift lever into third, and let the clutch back out. Instead, you opt to double-clutch properly:


First, you take your foot off the gas and kick in the clutch. You shift into neutral, AND let the clutch out. You wait perhaps 0.3 to 1.0 seconds for the engine to slow down from its high revs, depending on how fast you were revving when you started to shift and how much inertia the engine has to slow down. THEN you kick in the clutch and shift into third, and let the clutch out quickly, feeding the gas appropriately. If you have judged it right, when you let the clutch out, there isn't any JERK. And when you shove the lever into third, the gears and engine are at a synchronized speed, so there's minimum wear on the synchronizers, which are the tiny clutches that bring the clutch plate and the gears into smooth synchrony. There's also usually less wear on the clutch plates.


What's the big deal? The main point is that when you try to shift into third gear, the engine has slowed itself and the clutch plate down to the right speed—just about the same speed as the gearbox—so it saves wear on the synchronizers and the clutch. It can also save shock and strain on the whole drive-train, because the speeds are just about synchronized when you let out the clutch.


Well, big deal, you say. Cars haven't needed double-clutching since the synchromesh transmission was popularized 50 years ago. Why bother? Why fool around with anachronistic motions? Isn't it just buying trouble? Even Tom and Ray Magliozzi* claim that double-clutching is silly and stupid and wasteful of energy. Ah, but I can give you reasons why it is beneficial.


First, in most cars, the actual gears are always in constant mesh, and the synchronizers only decide which pair of gears to connect to their shaft. But many trucks and some racing cars are still set up with a non-synchromesh gearbox. With trucks, because they have so many gears, it's noticeably more efficient not to have all of the gears in mesh all of the time. So with the "crash-box," you HAVE TO double-clutch, or you will not be able to shift. The same holds true for racing cars—to gain the last couple percent of efficiency, only one set of gears is in mesh at any time, and you have to actually synchronize their speeds or you can't get it in gear. Despite the obvious drawbacks of having to double-clutch, the gearbox is stronger and more efficient than a comparable synchromesh one, and has less tendency to overheat.


Other reasons for double-clutching: Because it is the right way to operate the clutch. Because it saves wear and tear on your synchronizers in the long run, if you're planning to run your car over 200,000 miles, as I do. Because it is fun to do. Because in very cold weather, (-10° F, for example) you may have to double-clutch to shift gears at all, at least for the first few miles.


One very important reason is that, if your clutch linkage ever fails, you can still shift and get home by double-clutching, getting the engine and gears' speeds synchronized and then just EASING the shifter into the right gear. In the last 1,050,000 miles of driving VWs, I have lost my clutch about 3 times, and each time, with careful planning, I've been able to drive home safely. One time I pulled into the Customs House at Calais, Maine, and discovered my clutch was out. I eased along carefully and managed to get all the way home, 350 miles, to Boston, where it was convenient to put the car in the shop to have the clutch repaired—much more convenient than in the middle of a vacation, or the middle of Maine.


Another reason is that on some old cars, first gear isn't synchromesh, so if you need to shift into first without coming to a full stop, you have to double-clutch. Also, a lot of cars these days are made with weak, chintzy synchros, so they soon wear out, and to drive them gracefully, you need to double-clutch.


Note, when down-shifting, you have to shift into neutral and then blip the throttle momentarily before you shift into the lower gear. It requires practice and a good feel, a good touch, to do it right, especially considering the embarrassing noises you make if you miss your shift into a low gear on a crash-box. For example, you should aim to have the revs just a little high, so if you miss, the engine will soon slow down, and then gears will be at the right speed to mesh and the cogs will slip in....


OKAY, Pease, I'll try this double-clutching some day; but why do you bring up all this stuff in an electronics magazine? Ah, there's an excellent analogy: In most conventional switching regulators, the power transistor turns on while there's lots of voltage across it, and after it turns off, the voltage usually increases to a large voltage. When the transistors turn on, the diodes are already carrying significant current, and the transistors have to turn the diodes off. This is all somewhat stressful, and causes the transistors and diodes to have large turn-on and turn-off surges—pulses of power on every cycle. Of course, diodes and transistors have been designed to withstand these stresses and surges with excellent reliability; we see them all the time.


Still, people have specially designed "resonant mode" switchers to have zero-voltage and zero-current switching. In these regulators, most turn-on and turn-off stresses are eliminated, because the transistor is at a very low voltage when you turn it on, and at a very low current when you're ready to turn it off. Consequently, most voltage and current transients are greatly decreased. Less filtering and shielding is therefore required, enabling the complete regulator to have low Radio Frequency Interference (RFI). Now, to design such a supply takes a more complicated controller IC, more expensive parts, a very careful layout, and a lot of expertise in the electrical design. So while you get some advantages, you have to pay for them.


Now, when you want to build a compact, high-performance, switch-mode regulator at switching frequencies up to about 1 MHz, conventional switchers can do at least as well as resonant ones in terms of cost, size, and performance. But if you need a switcher even smaller and faster than that (most users do not), when the switching frequency rises above 2 MHz, the resonant-mode switchers begin to show real advantages.


At this time, National doesn't make these resonant-mode switchers, so I can't offer you any detailed info about all of their advantages and disadvantages. But I have explained most of their key features. And now you can see why the smooth, stressless turn-on and turn-off of the transistors and diodes in these resonant-mode switchers are analogous to double-clutching your shifts.


Comments invited! / RAP
Robert A. Pease / Engineer


P.S. Even if you double-clutch your shifts most of the time, as I do, do you know when it's a good idea NOT to double-clutch? My primary answer would be either when you're in complicated traffic and you don't want to fool around, or when you're really struggling on an upgrade and a speed-shift prevents you from losing speed. So, as it is with every rule, you should be aware that there are times when the rule doesn't apply. Some day I'm going to write a column about that topic....

............................
 

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SteveLevin said:
If you are a beginner, focus on driving the line and then worry about being in the right gear later. I've seen more people blow shifts, or just flat out drive off the track, worrying about shifting than I can count at HPDEs. . . But being in the right rpm range is never more important than having the car where it is supposed to be.
Ok, help me out here. Why would you suggest such a thing? This is like telling a new driver to practice driving around in traffic before they are at all familiar with how to start from a standing stop or shift gears in a manual transmission. Learning this way is possible, but it's far easier to learn how to shift first, then put that to use in a high-pressure environment. Ignoring the ease of learning, it still prevents you from learning the wrong way to drive around the track, then trying to unlearn that while learning to do it the correct way.

Additionally, (a major) part of driving the line is being in the right gear. "The Line" isn't just about position; it's also about the state of the car at a given position, like a string of vectors on steroids. The line for driving around the course in the wrong gear is different than that for the correct gear.

Am I missing something?
 

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OKAY, Pease, I'll try this double-clutching some day; but why do you bring up all this stuff in an electronics magazine? Ah, there's an excellent analogy: In most conventional switching regulators, the power transistor turns on while there's lots of voltage across it, and after it turns off, the voltage usually increases to a large voltage. When the transistors turn on, the diodes are already carrying significant current, and the transistors have to turn the diodes off. This is all somewhat stressful, and causes the transistors and diodes to have large turn-on and turn-off surges—pulses of power on every cycle. Of course, diodes and transistors have been designed to withstand these stresses and surges with excellent reliability; we see them all the time.


Still, people have specially designed "resonant mode" switchers to have zero-voltage and zero-current switching. In these regulators, most turn-on and turn-off stresses are eliminated, because the transistor is at a very low voltage when you turn it on, and at a very low current when you're ready to turn it off. Consequently, most voltage and current transients are greatly decreased. Less filtering and shielding is therefore required, enabling the complete regulator to have low Radio Frequency Interference (RFI). Now, to design such a supply takes a more complicated controller IC, more expensive parts, a very careful layout, and a lot of expertise in the electrical design. So while you get some advantages, you have to pay for them.


Now, when you want to build a compact, high-performance, switch-mode regulator at switching frequencies up to about 1 MHz, conventional switchers can do at least as well as resonant ones in terms of cost, size, and performance. But if you need a switcher even smaller and faster than that (most users do not), when the switching frequency rises above 2 MHz, the resonant-mode switchers begin to show real advantages.


At this time, National doesn't make these resonant-mode switchers, so I can't offer you any detailed info about all of their advantages and disadvantages. But I have explained most of their key features. And now you can see why the smooth, stressless turn-on and turn-off of the transistors and diodes in these resonant-mode switchers are analogous to double-clutching your shifts.

............................

I dont think i have ever heard someone draw an analogy between switchmode ps and double clutching... thats pretty inventive although its probably lost on most people.. (i use LM2592's regularly but nothing approaching 1mhz)
 

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First, in most cars, the actual gears are always in constant mesh, and the synchronizers only decide which pair of gears to connect to their shaft. But many trucks and some racing cars are still set up with a non-synchromesh gearbox. With trucks, because they have so many gears, it's noticeably more efficient not to have all of the gears in mesh all of the time. So with the "crash-box," you HAVE TO double-clutch, or you will not be able to shift. The same holds true for racing cars—to gain the last couple percent of efficiency, only one set of gears is in mesh at any time, and you have to actually synchronize their speeds or you can't get it in gear. Despite the obvious drawbacks of having to double-clutch, the gearbox is stronger and more efficient than a comparable synchromesh one, and has less tendency to overheat.
Small technicality, but in a racing gearbox, and I think even in a synchro gearbox, the gears are always in mesh. It's just that only one is transmitting power at any time. The gear on the mainshaft (pinion shaft) is free-wheeling when not driven, whereas its mate on the layshaft is spinning with the engine. When you shift into a specific gear, one of the dog rings, which are splined, not free-wheeling on the pinion shaft, is moved laterally until its dogs engage the dogs on the side of the gear you're engaging.
 
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