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Old 08-26-2005, 11:07 AM   #17
SD987
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Join Date: Jun 2005
Location: San Diego, California
Posts: 874
Limoncello, thanks for that link, interesting reading.

I don't claim to be 'Joe-driver', and just like anyone else, my tendencies come from how I was originally taught and personal experience driving manual cars from day one. That being said, I've found the following tips to be helpful in improving performance.

In my experience the timing of the pedal movement is actually secondary to making the correct movements. What do I mean? How hard can it be to press three pedals?

Well it’s like a golf swing, if the same basic movements are done with the wrong muscle groups instead of the right ones, it’s pretty hard to hit a perfect shot, no matter how you time it. The first thing I would recommend is to actually stick your head in the footwell (preferably when no one else is around) and see how the pedals are configured; look behind the gas pedal. Automotive engineers are pretty smart people and they don't place the pedals in a car without one, consideration for human physiology and two, the time honored art of performance driving.

A. For a human to exert maximum force with their feet, involves the leg muscles motivating first the heel muscles which serve to align the primary muscle group below the arch for optimal application. Lastly the muscles toward the front of the foot below the toes fully extend to apply smaller but more precise amounts of force. When releasing that force, the heel actually starts first, down and slightly forward to serve as a pivot point of reference for the rest of the foot.

B. The brake and gas are located close to each other, obviously because the same foot controls them, but also to perform classic heel-toe shifting, in which the right foot operates both pedals simultaneously.

How does A + B translate into action?

1. The gas pedal is meant to be operated with the right half of the right foot (think of using the outside foot muscles) and pressed down and up to the right (northeasterly), oddly enough, the same direction that the pedal is pointing. If you’re someone who pushes the gas pedal straight down, with the inner/stronger foot muscles (the natural tendency), you’re going to tend to lug the engine and have difficulty. The ability to modulate the throttle response pushing as I suggest, versus straight down is night and day and essential if you were to actually give heel-toe shifting a shot.

2. Brake pedals are meant to be pushed down with the inner leg muscles and left top side of the right foot. The brake response between doing this and just jamming on the brake with your whole foot isn’t remarkable, but using that part of the foot improves switching speed between brake and gas which is key. Initial alignment of the right foot at rest should be to the brake pedal.

3. The clutch pedal is also engaged by pushing down and forward with the inner part of the left foot to maximum extension (of the arch), and is released by initiating with the heel as I mentioned above. Many drivers don’t fully extend their arch (and thus the pedal) when putting the clutch in, which is helpful to smooth shifting. The combination of the heel initiated release and relaxation of the arch muscles from full extension is engineered into the “take-up” built into the clutch pedal, i.e. the amount of required release during which little noticeable happens before the point of engagement when your primary muscle group and toes come into play. I think alot of drivers initially control the release of the clutch from the front/toe area creating labored starts, e.g. riding the clutch. Without employing the heel area as a reference point, your left foot is a ship without a rudder. These folks not surprisingly find that they shift smoother when they don’t push the clutch all the way in, just until they are below the engagement point (the clutch slip area). Because they can’t get the timing of the take-up right, they skip the whole take-up step but are reducing clutch life. Using the clutch slip area to hold yourself on a hill is even worse...

Move purposefully and with confidence. Tentative movements while driving are like decelerating your putter…However, don’t make your feet stiff as a board, otherwise you’re running counter to everything I suggested above. A bad tendency people have is to delay the gas. As soon as that gear clicks into place, apply gas. Even during what seems like a momentary delay your car is actually foundering (has no drive to the wheels) and is slowing down. People have too much pause in all gears, but mostly they seem to do this in first gear, which is the natural tendency after years of tentatively pulling out of first for fear of stalling out.

When using the shifter in the Box use your wrist muscles more than your fingers. The wrist muscles are stronger and the Porsche shifter is heavy, but more importantly the wrist muscles have a limited range of movement which also match the movements built into the shifter. If you wiggle your fingers, they can go all over the place but this is an instance where flexibility is less desirable than strength and muscle-matched engineering.

To be in optimal position for manual driving I would do a couple of things.

Unless your arms and legs are proportioned like a baboon I suggest you push yourself back a little. Most drivers I see are too close to the wheel and pedals. Move back to a point where with your arms extended, the top of the wrist joint overhangs the steering wheel; and your legs (with the clutch pedal pushed fully in) are extended but to a point well before your knees lock. Your knees should be slightly bowed out but not touching the center console (right knee). This will put you in that maximum force position when the clutch pedal is fully depressed and facilitate using the outside/right portion of the right foot when applying gas. People who sit too close are also putting themselves in real danger if the air bag is activated. Manufacturers recommend a minimum of 10 inches from the air bag.

Some readers of this post may say..."no kidding" to most of these or think I’m full of crap. That’s OK, and I'd welcome other points of view or disagreement, but maybe something we add in this thread will make someone shift smoother, launch faster and have more clutch life.
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