the slip: shifting without using the clutch

[p38fln]

Also, I think one of the most overlooked ways of saving fuel economy on a vehicle witha stick shift - don't rev the engine up to get going, ESPECIALLY if you have a computer controlled car. GENTLY ease up on the clutch, and once it is all the way up and you're rolling, THEN give it gas. Doing the gas and clutch at the same time wastes a lot of energy as heat.

[winkosmosis]

Originally Posted by p38fln

Also, I think one of the most overlooked ways of saving fuel economy on a vehicle witha stick shift - don't rev the engine up to get going, ESPECIALLY if you have a computer controlled car. GENTLY ease up on the clutch, and once it is all the way up and you're rolling, THEN give it gas. Doing the gas and clutch at the same time wastes a lot of energy as heat.

That's how you stall. I guess unless your engine is a big V8.

[p38fln]

I routinely did it with a 1999 Rav4 with a 4 cylinder engine - it took a bit longer to get rolling that way but it never stalled.

[Varn]

Winki
For some reason my vw diesel 1.6 can actually go without throttle from a dead stop. I do use the clutch of course. For some reason there is a lot of low end torque and maybe a lot of flywheel. It is a curious little car.

[comptiger5000]

Most computers will automatically throttle up a bit to try to prevent a stall. However, on an engine with not much low end torque, it's a bad idea, as you end up slipping the clutch far more to get moving.

[p38fln]

It was a technique taught in truck driving school in the driving semis for fuel efficiency class that I never believed would work in a car either - until I tried it. Basically, you let halfway up on the clutch, let the vehicle start rolling, then let all the way up on the clutch then give it gas after the clutch is all the way up. They said it cuts down on clutch wear too. It was still on its original clutch at 157,000 miles when I traded it in for a Ford Ranger, and I wasn't exactly an easy driver on that old Rav4 either.

[Varn]

Comptiger,
The less power (and heat) that the clutch has to adsorb the less it wears and the less fuel you will use to get started. Cost to implement is zero as well.

[justjohn]

I have a related question.

When trying to rev match to engine brake, is coming in with rpms a little low or rpms a little high better in terms of wear and tear on the clutch/transmission?

[comptiger5000]

I'd say coming in a little high is probably better for wear, as the revs are already falling as it engages, vs the clutch having to pull them up against engine braking.

[jtbo]

Originally Posted by winkosmosis

That's how you stall. I guess unless your engine is a big V8.

Oh no, I can easily just lift foot from clutch and car gets going, while finding parking spot I don't touch accelerator at all, same with when taking off, I just lift foot off from clutch.

Mine is 1.9l diesel, but have been doing this with 2.0l gasoline motor too in my other car.

Modern cars will stall unless they have stupid automatic throttle control, which will add more throttle, modern cars have very thin torque at idle, when older engines have strong good torque at idle.

That is at least how it is in euro cars.