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PMPB · 07-09-2013, 02:02 AM

Good lord, some of the advice on here is really bizarre. Some people seem to think the clutch cannot ever be slipped because you're wearing it out.... Guess what, the clutch is a consumable.

Don'ts:
1. Let the clutch out slowly at high revs. For example, holding the clutch on the biting point at 3500rpm for several seconds would be bad. You'll smell it.
2. Slam the shifter from 1st to 2nd. Because we have a large gap in ratios between 1 and 2, it's better to give the synchros a bit more time to work, just slow that shift down, just a fraction, and feather the clutch slightly to avoid badly jerking. Trust me, jerking badly (forward/backward rocking from letting clutch out too fast) is just as bad a little slip to help the engine RPM slow down to match the drivetrain speed.
3. This engine likes a little RPM. The 'diesel' noise it makes below 2000rpm during acceleration isn't bad, it just loading + DI pounding fuel into the cylinders, but it's not great either. I aim to shift around 2500rpm, and expect to be back in gear at no lower than 1900rpm.

It's not possible to always start moving with the clutch in 1st before applying ANY gas, also the rpms will dip below the 600rpm idle (which our engine HATE). Anybody who says that's the normal way to drive, lives in a rural area where they have all day to go somewhere and no traffic.

Normal 1st gear accel would be something like
1. Start releasing clutch (with experience it will be easier to release the clutch to just before the bitting point)
2. Barely touch the gas, the rpms will climb (maybe 800-1100rpm) while you simultaneously hit the biting point.
3. Smoothly apply more throttle while letting out the clutch reasonably slowly. This is where practice will make you better. Too fast and the engine bogs, too slow and the RPM's really climb and you are needlessly wearing the clutch. To have any hope of pulling away from a stop at a good steady speed, your RPM's will be in the 1000+ range and varying (maybe 800-1400, or more) depending if you are going up a hill, if you car is heavily laden, if you are blasting away from somebody about to rear-end you, if you are going down a hill, you may use very little gas, and be able to fully release the clutch quickly.

At the end of the day, you need to remember that the clutch is meant to smoothly transfer the power of the engine to the rest of the drive train. How smooth you want to be, and how quickly you need to increase that power transfer dictates how fast you release the clutch.

DON'Ts
1.The same as you would never drive around with your foot slightly on the brake pedal, don't drive around with your foot slightly on the clutch.
2. Don't hold the car on a steep hill with gas/clutch. That said, if you've creeped up to a stop sign that's on a hill, and you just need to stop for a second before accelerating again (empty intersection), there is no reason you can't just depress the clutch slightly so that it slips for 1/2 a second. Why come to a full stop with the brake pedal, only to have to jump on the gas quickly slipping the clutch to greater degree again. I'd come to full stop if I was waiting for a pedestrian or another vehicle to make its manoeuvre.

07-09-2013, 02:02 AM	#118
PMPB Senior Member Join Date: May 2013 Drives: BRZ Sport-tech Location: Canada Posts: 347 Thanks: 77 Thanked 182 Times in 111 Posts Mentioned: 0 Post(s) Tagged: 0 Thread(s)	Good lord, some of the advice on here is really bizarre. Some people seem to think the clutch cannot ever be slipped because you're wearing it out.... Guess what, the clutch is a consumable. Don'ts: 1. Let the clutch out slowly at high revs. For example, holding the clutch on the biting point at 3500rpm for several seconds would be bad. You'll smell it. 2. Slam the shifter from 1st to 2nd. Because we have a large gap in ratios between 1 and 2, it's better to give the synchros a bit more time to work, just slow that shift down, just a fraction, and feather the clutch slightly to avoid badly jerking. Trust me, jerking badly (forward/backward rocking from letting clutch out too fast) is just as bad a little slip to help the engine RPM slow down to match the drivetrain speed. 3. This engine likes a little RPM. The 'diesel' noise it makes below 2000rpm during acceleration isn't bad, it just loading + DI pounding fuel into the cylinders, but it's not great either. I aim to shift around 2500rpm, and expect to be back in gear at no lower than 1900rpm. It's not possible to always start moving with the clutch in 1st before applying ANY gas, also the rpms will dip below the 600rpm idle (which our engine HATE). Anybody who says that's the normal way to drive, lives in a rural area where they have all day to go somewhere and no traffic. Normal 1st gear accel would be something like 1. Start releasing clutch (with experience it will be easier to release the clutch to just before the bitting point) 2. Barely touch the gas, the rpms will climb (maybe 800-1100rpm) while you simultaneously hit the biting point. 3. Smoothly apply more throttle while letting out the clutch reasonably slowly. This is where practice will make you better. Too fast and the engine bogs, too slow and the RPM's really climb and you are needlessly wearing the clutch. To have any hope of pulling away from a stop at a good steady speed, your RPM's will be in the 1000+ range and varying (maybe 800-1400, or more) depending if you are going up a hill, if you car is heavily laden, if you are blasting away from somebody about to rear-end you, if you are going down a hill, you may use very little gas, and be able to fully release the clutch quickly. At the end of the day, you need to remember that the clutch is meant to smoothly transfer the power of the engine to the rest of the drive train. How smooth you want to be, and how quickly you need to increase that power transfer dictates how fast you release the clutch. DON'Ts 1.The same as you would never drive around with your foot slightly on the brake pedal, don't drive around with your foot slightly on the clutch. 2. Don't hold the car on a steep hill with gas/clutch. That said, if you've creeped up to a stop sign that's on a hill, and you just need to stop for a second before accelerating again (empty intersection), there is no reason you can't just depress the clutch slightly so that it slips for 1/2 a second. Why come to a full stop with the brake pedal, only to have to jump on the gas quickly slipping the clutch to greater degree again. I'd come to full stop if I was waiting for a pedestrian or another vehicle to make its manoeuvre.