some questions on driving manual

[JadeButterfly]

i haven't had a chance to drive my car much (about 500km over three weeks!) because of final exams and all...but i try my best to take out it during the nights for coffee run.

anyways just a few questions about driving manual as I'm still new to it.

1) From stop, once I release the clutch to the friction point, then apply gas... i can feel that some vibration coming from the clutch. I assume its because its trying to catch on. Is this vibration normal? Every time I feel this vibration, I have the tendency to let my clutch out faster, but end up stalling. If I let it vibrate for a good second at the friction point, its ok, but I'm afraid of learning the bad habit of "riding the clutch"

2) Rev-matching. I've been practicing quite a bit and its getting smoother and smoother. But I want to make sure I'm doing it right. From many sources, it sounds like your suppose to bring the rpm to the "exact" amount to match the rpm when downshifting. unfortunately I don't know my car that well to know this exact amount. Instead, when im coming down from 6-5-4 (normal street driving), i've learn to blip the throttle about 1000rpm, then let the clutch out smoothly so it catches on. It's smooth, but not butter smooth as some describe. from 4-3-2, I give it about 1500rpm. In both cases I'm over throttling because I don't know exactly what rpm I should be in afterwards. The motion I do it in is clutch in --> blip the throttle --> downshift --> clutch out.

3) Downshift to turn. I don't normally rev-match when approaching a turn unless the road is kinda clear, whereby I would rev-match before the turn. What I normally do is brake to slow down to about 20kph...clutch in....shift to second...and once i start turning, clutch out slowly while braking, then start accelerating once I clear half the turn. I understand that heel-toe would be the advance technique to this, but I haven't really mastered rev-matching to try heel-toeing yet...

I guess my question is, am I doing this correctly for a new driver? Hopefully I can get some constructive criticism so I can improve. Also, "riding the clutch" seems like a taboo for manual drivers...but aside from wearing out the clutch earlier (which can be replaced, just $), does it "damage" anything? Same with stalling at a stop, does it damage anything in the long run? Also, how much beating can the clutch take? Am I expecting to replace my clutch before 5k? 10k? 20k? cuz I'm learning on it?

thx, i appreciate your advice :)

[victor_t]

"riding the clutch" as I understand it is driving with your foot on the clutch instead of the dead pedal, meaning you're always applying slight pressure on the clutch.
could be wrong.

for your first question: I was also afraid of burning my clutch so I was letting out the clutch too fast, which results in some nasty wheel hop in first and second gear.
my friend (who has been driving only standard all his life) insists that I should let it out gently/slowly/ when he drives my car there is absolutely no wheel hop.
so I started doing it that way too, and shifting is much smoother.

yes, I feel some vibration in my clutch. In the beginning I thought it was "chattering" when I was areleasing the clutch while accelerating, but then I discovered that I feel a slight vibration even when the car is stopped: with the car on a level terrain and the transmission in neutral, if I press the clutch at some point in the middle of the travel, sometimes I feel a slight vibration. could be coming from the hydraulics.

for the rev matching: generally there's 700 to 1000 RPM difference between the gears, and about 20 km/h differnce (on a 5 speed, my opinion)
meaning that if you're doing 40km per hour in second gear at 3000 RPM, you'd be doing 2000RPM in third gear, and 3000RPM in third at 60 km/hr
this is not necessarely true for fifth gear anymore, it's 3000RPM at 120

but anyway, I don't think the point is to bring the revs to the exact RPM, I don't think it's possible either (the moment you release the gas, the motor starts to slow down anyway)
the point is to bring the RPM closer to where it should be so the clutch doesn't need to accelerate the motor.

if you don't rev match, as you release the clutch (slowly) first you'll feel the car breaking when the clutch starts engaging. then when clutch overtakes the inertia of the motor and starts accelerating the motor, the car stops breaking and the motor speeds up. if you blip the throttle and increase RPM about 1000 before, the release of the clutch will be much smoother. it's also easier for the clutch to engage with a motor that is naturally slowing down (let's say the speed is 3000RPM and it should be 2700RPM. the motor is already slowing down, helping the clutch. if you're at 2500 with motor slowing down, and speed should be 3000, the clutch must accelerate the motor and also fight the inertia of the motor, and this requires more force than the first scenario)

all of this couldb e wrong. I'm also a shift newbie.

[slam525i]

1. The vibration usually isn't from the hydraulic clutch but from the firewall. (i.e. you're feeling it through the car) If you're letting the revs drop significantly, this will be more noticeable. Regardless, it's "normal". It's okay to slip the clutch to 1st, as long as your revs aren't too high. You can't drive smoothly without some clutch slip.

2. You can't rev match "by numbers". You're not that good at mental math (and nor are the rest of us) and you'll spend too much time looking at the tach. Learn to do it by feel/sound. Also, if you try to nail the exact RPM with the throttle, you'll spend too long playing with the throttle. Just blip and then slip the clutch back out when you're about the right RPM.

3. Yes, heel-to-toe would be better, but requires a lot of practice. Worry about that later.

Seriously, don't worry that much about clutch wear. Some people jump on and off the clutch to save it, and instead send huge spikes in load through the drive train and wear out their tires.

Most clutch wear doesn't come from slipping the clutch with low speed differences. It comes from having a large difference between engine and drive train speed. The clutch has more energy to dissipate when it has a larger difference in speed to match.

The best ways to save your clutch: don't hill-hold with the clutch, rev match your shifts (up and down), keep your foot off the clutch unless you're pressing it, avoid starting in 2nd gear.

As for how long before it's worn out, obviously it depends on city vs. highway, driving style, etc. etc., but I believe most should last well over 100k. (I'm not familiar with the typical number for Mz3)

Isn't it fun driving a manual? :bana2