Bad Driving Habits (M/T)

kenchan

it can start even 1500 if you ride the clutch long enough.

ZMan8

That's tough to answer because you can damage the clutch by riding it at 1500 rpm and 5000 rpm. 5000 will put more of a load on there which leads to more damange. But say you slip the clutch for 5 seconds at 5000 rpm and slip it at 1500 rpm for 20 seconds. Then i'm not sure which one is worse.

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2010 370Z 40 Anniv., 6 MT | Fast Intentions | Swift Springs | SPC | Z1Motorsports | JWM | Redline Oils | 35% Window Tint
2015 Mazda6 | 370ZChicago: Chicago Area Cars & Coffee

AlphaSnacks

All RPMs cause 'damage' to the clutch - the clutch is a friction disk that wears every time you use it, just like your brake pads do. Don't be terribly afraid of the wear - it is designed to function that way. If you're excessively slipping the clutch at high RPMs, you're causing more wear. For example, you can cause the same amount of wear to the clutch by slipping it for 2 seconds at 5K RPM - as you would by slipping it for 6 seconds at a more generous 1800-2000RPM.

I sometimes double-blip the throttle when I take off. One blip to about 2K as I let off the clutch and feel the engagement, and immediately the second blip is to catch and hold the RPM around the 1500RPM mark as I accelerate and slip for about 2 seconds or so. I don't find myself doing this on other MT cars - cars like BMWs and Audis have much more linear throttle response. Where as the throttle on our cars is a little crazy and inconsistent and can feel different every 20 minutes.

There is nothing wrong with slipping the clutch. 2 seconds on a flat road at lower revs, and about 3 seconds on a hill with moderate revs is okay. You'll know if you're cooking the clutch...burned clutch smells like tire smoke + garbage. But again, it takes quite a bit of stupidity to cook a clutch during normal driving.

Augustus

Yeah, ZMan & kenchan, that's what I was wondering.

Like if there was sort of an optimal guideline for a normal speed, low-impact, standard start. I realize that every situation is a little different; desired 'launch' speed, uphill/downhill start, ambient temps, traffic conditions, vehicle loading, whether there's a hottie in the lane next to you, etc.

So engaging the clutch at 1,200 -1,500 RPM, do you allow the RPM's to fall a bit as the clutch engages and the car begins moving? Or do you modulate the throttle to keep the RPM's steady as you fully engage the clutch? Tough question, I realize.

With my near-bog technique/habit, I'm modulating the throttle to keep it around 1k, as I've got to to keep it from stalling.

AlphaSnacks

Far more torque down low than a Z to allow either car to just get on up and go off the clutch.

Isn't that necessary in an S2K? In a 370Z you can coast at 5MPH without even a slight buck and comfortably accelerate - I do this a lot at yield, slow down, school bumps, and even stop signs - no qualms from the car. Again, that's because the Z has enough torque to maintain the momentum in 2nd gear at 5MPH.

I've driven an S2000 ages ago, and I recall it not liking being in 2nd gear at anything below 5MPH, you felt it as soon you slowed down past 10MPH in fact.

AlphaSnacks

Professional Nerdism at it's finest.

ZMan8

I try to keep my revs >1000 when I'm engaging in 1st.

So here is my process say at stop light flat surface:
1. Disengage clutch (press in clutch pedal) & lift foot off brakes
2. Start to release clutch and about a little before the engagement point I rev up to around 1200-1500 rpm.
3. Once I feel the clutch start engage, I continue maintatin the revs to keep from stalling/chattering
4. as the clutch engages more I start to apply more throttle (the key here is smoothness).

__________________
2010 370Z 40 Anniv., 6 MT | Fast Intentions | Swift Springs | SPC | Z1Motorsports | JWM | Redline Oils | 35% Window Tint
2015 Mazda6 | 370ZChicago: Chicago Area Cars & Coffee

Augustus

Thanks Arnold K. That's the kind of info I'm curious about.

Yeah, I know the smell from being around others doing stupid things in manual cars. Out of curiosity, what actually makes the smell? Just the friction material of the clutch being overheated/burned?

alcheng

You can even do that in 3rd gear if the clutch is in good condition.

My friend study auto-mechanic in college here, his instructor told him this is one of the method to test the clutch.

Of course, don't do that always!!

kenchan

yep, rpm falls a little bit while engaging. i dont modulate the throttle and engage the clutch linearly if just a regular start. if over bumps, crawling, over r/r crossing, uphill, etc i modulate a little bit case by case.

Nick911sc

I take this as a complete compliment! haha

Red__Zed

Most people that do that test are looking for the car to stall, by releasing the clutch in 3rd.

alcheng

LOL, seriously, I tried it on a manual car, it won't stall, you have to release the clutch very slowly, it determines is your clutch still give enough friction.

But since you have to release the clutch so slowly in 3rd, that's why it shouldn't perform often.

kenchan

there was some stupid contest in japan some time ago where you take your highest gear and see if you can get the car going without stalling... without throttle input.

Nick911sc

I would like to see this stupid contest if footage is available! haha