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How many of you are doing it? Do you do it all the time or only on special occasions? Just learned about it and trying to figure out if it is worth the pain of learning to do it. Does it do anything for our 92x
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I almost always do it when I downshift, it makes a huge difference in terms of the notchy feel of the transmission. I don't really bother when upshifting because the synchros in our car do their job pretty decently when upshifting. You can get rid of some more of the transmission notching if you do double clutch when upshifting though.
I don't think it's a pain to learn at all, it takes all of 2 seconds to learn if you understand the concept and then it takes a day or two of driving to speed up enough that it's usable. I learned when I started driving about 8 years ago and the only vehicles I've found it to be completely uncessary on were a few BMWs (of course you could change gears in these cars without the clutch if you were in the 3k-3.5k RPM range - that says a lot about the precision of their transmissions)
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So how would you double clutch? Can you give me an example? And do people do heel toes?
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i double clutch every downshift, not that it is needed, but out of habit.
The sequence is pretty simple to do but hard to explain:
When moving your right foot to the brake make sure that it is to the right of the pedal so you can hit the gas pedal;
as you brake with your right foot push the clutch in with your left;
when the clutch disengages shift from your current gear to neutral;
let the clutch engage;
now comes the fun part: remember that with your right foot is still braking roll it to the right and depress the gas slightly, enough to match the rpm on the engine with the speed you are going for the gear you are into i.e. if you are shifting to 4th from 5th and the car is going 30mph, the engine speed in 4th gear is approx 1600 rpm, so rev the engine to 1600 rpm;
disengage the clutch and complete your downshift;
re-engage the clutch;
Whew, now repeat for the next down shift.
It's actually easier than it sounds. When done right the downshifts will be much easier as you are doing some of the work of the synchros, and the engine will be at the right rpm when you engage the clutch in the next lower gear so should be smoother as well.
My only beef with the 9-2x is that the gas pedal is a little high or the brake is a little low. Either way I tend to get a little too much rpm when I heel & toe down. Nothing a pedal cover on the brake wouldn't solve.
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I always double clutch (not just rev matching) and use heel toe on my cars. Ever since I learned on a Formula Dodge (no synchros in the gearbox), I've continued to do it.
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im trying to learn ... but im still getting used to driving stick for the most part since this is my first stickshift and its got 1k now. As of right now, I am beginning to practice getting my downshifts timed right and done quickly by rolling around 2k and downshifting a gear by blipping the throttle and changing gears quickly. I dont get it right usually but I am getting better. When i get that down, im going to try to learn heal and toe. I also have a bit of trouble with starting from a stop as well as the shift between 1 and 2nd
Last edited by akaryrye (2005-06-03 19:30:10)
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tonka92x wrote:
My only beef with the 9-2x is that the gas pedal is a little high or the brake is a little low. Either way I tend to get a little too much rpm when I heel & toe down. Nothing a pedal cover on the brake wouldn't solve.
FYI: Regarding the brake pedal...By buddy adjusted the pedal height on his 02 WRX...I assume it would be the same on our 92s
He heal/ toes all the time too....Former E-Production racer...
I think I will see if I can adjust mine sometime soon, then learn how to heel toe better...Its hard for me to walk and chew gum... :-)
Cheers,
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I'm just starting to try to get better at this. I was doing it today but it wasn't seeming to produce smoother engagement compared with just regular shifting. I probably just need a bunch more practice, but I've only had the 9-2X for about three days now.
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Haha, I was doing this without ever knowing what double-clutching actually was! It just made good sense with the tranny set up the way it is. I'll have to give it a try on my dad's mini S now. Still working on the heel-toe, though, I've only done it correctly once or twice in the gravel.
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CryderSpeed wrote:
Haha, I was doing this without ever knowing what double-clutching actually was! It just made good sense with the tranny set up the way it is. I'll have to give it a try on my dad's mini S now. Still working on the heel-toe, though, I've only done it correctly once or twice in the gravel.
Just to note, double clutching is not rev matching. It sounds like you may be thinking rev matching, but I could be wrong...
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I've been trying to double clutch but this car seems to drop revs much faster than my Prelude did so I having to learn to much faster doing it.
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eurospeed wrote:
CryderSpeed wrote:
Haha, I was doing this without ever knowing what double-clutching actually was! It just made good sense with the tranny set up the way it is. I'll have to give it a try on my dad's mini S now. Still working on the heel-toe, though, I've only done it correctly once or twice in the gravel.
Just to note, double clutching is not rev matching. It sounds like you may be thinking rev matching, but I could be wrong...
Well, I was doing it while braking, not just with the clutch in, that's what we're talking about, right? I'm a total noob as far as owning a performance car goes, so please correct me so I don't look like a tool in real life, lol.
Last edited by CryderSpeed (2005-06-14 22:24:30)
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CryderSpeed wrote:
Well, I was doing it while braking, not just with the clutch in, that's what we're talking about, right? I'm a total noob as far as owning a performance car goes, so please correct me so I don't look like a tool in real life, lol.
Hey man, we all need to start somewhere. Here is the sequence to double clutching on downshifting:
Let's say you are cruising steady in 4th gear and you need slow for a turn.
1) Depress clutch pedal fully
2) Pull stick to neutral
3) Release clutch pedal fully
4) Blip throttle to match revs of your down selected gear (3rd in this case)
5) Depress clutch pedal fully
6) Move stick to engage 3rd gear
7) Release clutch pedal fully while modulating throttle to power through the apex
Note, I did not include braking which would add in heel-toe braking while double clutching. Pure joy when you get the sequences right. Also note, that the whole sequence happens in much less than a second.
It was originally developed to shift synchroless gearboxes in older cars. The process essentially syncs up the speed of the fywheel (engine) with the driveshaft (differential) providing a much smoother transition in downshifting (used in upshifting on certain older cars also). Can you do it in today's cars with synchromesh transmissions? Hell ya, and I always do it. It actually saves quite a bit of wear on the dog teeth (gear like teeth that engage the real gears; part of the synchromesh assembly). Also, many people don't realize this, but when you are shifting gears, you really aren't...your gears in the gearbox are always in mesh and you are engaging through synchros....they are the grinding that occurs when you mis-shift.
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Ah, I see, said the blind man to his deaf dog. So double clutching is just a wear-reducing maneuver, then. I was experimenting with heel-toeing on gravel and got a few decent drifts, but that's not the idea on pavement, correct? Just a way to minimize throttle-off time, right? Man, I wish there was a track close to me!
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CryderSpeed wrote:
Ah, I see, said the blind man to his deaf dog. So double clutching is just a wear-reducing maneuver, then. I was experimenting with heel-toeing on gravel and got a few decent drifts, but that's not the idea on pavement, correct? Just a way to minimize throttle-off time, right? Man, I wish there was a track close to me!
Partly right about double clutching, but in gearboxes w/o synchros (older cars, some race cars, etc) double clutching is a must or you will trash the gearbox and have extremely unsmooth downshifts which will lead to a spin on the track.
Heel-toe can be done anywhere and I use it on everything I drive as well. All it is really is foot placement and it's yet another technique to provide a smooth transition from braking to acceleration. It doesn't really use your heel and toe either. Depending on the pedal setup, if you want to slow down, you essentially straddle the brake and throttle by placing the ball of your foot on the brake and the other half or so of your foot, slightly rotated, on the throttle. From there you downshift accordingly by rolling your foot to blip the throttle as needed with rev matching, all while maintaining smooth pressure on the brake pedal.
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I have been trying to work on my shifting technique and this is my first stick shift car, as well. I'm still not too good, but it's definitely really hard to gauge at this point because I'm trying like hell not to rev it over 4k. With less than 400 miles on the car, I've still got a ways to go until I can really open her up. At that point, I guess I'll see what this car can really deliver (and how crappy I am at shifting).
A question: For those of you past the break-in point and who have experience with stick shift, how difficult is it to achieve the quoted ~6 second 0-60 time in the Aero?
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RuinerXL wrote:
A question: For those of you past the break-in point and who have experience with stick shift, how difficult is it to achieve the quoted ~6 second 0-60 time in the Aero?
I just completed break-in today and worked my way up to around 6K. There are a few interesting quirks with the power delivery which I'm hoping the AccessPort may solve. I can tell you that, without thrashing the car on launch (something I definitely don't plan on), the 6 second time is near impossible. One thing though, the car is an entirely different beast past 4.5K and far more enjoyable. One of these days, I'm going to throw together a writeup on the 9-2x's performance traits and quirks.
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Heel-toe=braking into turn. The big trick to it all it to know when you should roll and blip. Too soon and it's just a wasted effort as the revs will have fallen by the time you're done braking and actually back on the accelerator. Too late and you will foul the transition from brake to gas. There's a precise moment just befor the apex when the downshift needs to be set into motion, and I think the only way to know is learn through experience.
A rev-matched downshift is much simpler. You need to downshift to accelerate, ot maybe you're coming off an exit ramp but aren't braking. In that case, you clutch, shift to neutral, blip the throttle to bring the revs up (usually 1500 rpm is a good guess, depending on how quickly you can physically shift gears), clutch, downshift and you're off.
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Chairman Kaga wrote:
Heel-toe=braking into turn. The big trick to it all it to know when you should roll and blip. Too soon and it's just a wasted effort as the revs will have fallen by the time you're done braking and actually back on the accelerator. Too late and you will foul the transition from brake to gas. There's a precise moment just befor the apex when the downshift needs to be set into motion, and I think the only way to know is learn through experience.
A rev-matched downshift is much simpler. You need to downshift to accelerate, ot maybe you're coming off an exit ramp but aren't braking. In that case, you clutch, shift to neutral, blip the throttle to bring the revs up (usually 1500 rpm is a good guess, depending on how quickly you can physically shift gears), clutch, downshift and you're off.
Not just setting up for a turn though. Heel-toe can be used in conjunction with double clucthing for a nice smooth braking transition when stopping for a stop light for example. In fact, I can't remember the last time I didn't heel-toe when braking. It's just so natural when you start doing it.
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I frequently heel/toe and revmatch but never bother double clutching (i omit steps 3,5 in Eurospeeds post above). Yeah i realize that double clutching is better on the synchros than just rev matching, but i'm lazy...
I was to forced to learn about heel/toe and revmatching after i had a lightweight flywheel installed in my RS. Whenever i depressed the clutch the revs would drop really fast, so one had to blip the gas for the down shift change to be smooth. It was a major pain having to adjust at the time, though looking back i'm quite glad i went through the experience.
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Double clutching is just a waste of time in the new tranny's, but heel toe-ing is awsome fun. i've been doing it for years in my jeep just to make it smooth, and 4 wheelin on slippery rocks it's usually best to be smooth. My wife's s40 has a weird brake pedal arrangement, so i can't do it on there b.c the brake sits in front of the gas pedal too far. but the 92-x is great for heel toe. did anyone find out if the pedals really are adjustable? i haven't seen anything else on that other than the one post earlier
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Dumbscout wrote:
Double clutching is just a waste of time in the new tranny's, ...
Perhaps in your opinion, but I couldn't disagree more. The dog teeth in a synchromesh assembly are made of soft metals, bronze, etc. Whenever you engage a gear, wear is occuring. If you help to match speeds by double clutching, even less wear occurs. Does it matter over 100K miles? maybe, maybe not, but as the mileage grows, it adds up. How many manual trannys have you driven where 1-2 is difficult on higher mileage cars? That's all synchro wear.
You are right, that it's not needed in modern transmissions with synchros and I believe it was pretty clear before, however in racecars such as Formula Fords, there are no synchros. That's what I initially learned the technique on and it helps to keep skills in check with a little side benefit of increase gearbox life.
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for those of you who need to see something to know how it works, i stumbled across this video
http://www.dragonsys.org/files/videos/B … E86x2.mpeg
when they start racing, pay close attention to the little box on the bottom left of the screen (especially when they are coming up to a sharp corner), it shows what the driver is doing with their feet. Slight modification to the technique may be required since our brake and gas pedals are closer together, but it should give a pretty good idea.
Last edited by akaryrye (2005-06-23 04:51:56)
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akaryrye wrote:
for those of you who need to see something to know how it works, i stumbled across this video
http://www.dragonsys.org/files/videos/B … E86x2.mpeg
ahhh... hot japanese girl in nurses outfit
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akaryrye wrote:
for those of you who need to see something to know how it works, i stumbled across this video
http://www.dragonsys.org/files/videos/B … E86x2.mpeg
when they start racing, pay close attention to the little box on the bottom left of the screen (especially when they are coming up to a sharp corner), it shows what the driver is doing with their feet. Slight modification to the technique may be required since our brake and gas pedals are closer together, but it should give a pretty good idea.
Off-topic. Anyone knows what they were trying to prove in the video? Skill more important than HP? Effect of weight? Size of the pole girl's boobs?
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