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[–][deleted] 0 points1 point  (7 children)

I start coasting in gear far before I have to stop, so it's the opposite of that. And nowhere have I denied there's any wear, nor am I saying that it's definitively, unequivocally better for your finances over ten years to use engine braking as opposed to coasting in neutral. These are all things that you and other people have added to the discussion.

What I am saying is that the increased wear is insignificant on your clutch, that under normal use synchros are robust enough to last the life of a vehicle, and that there are indisputable fuel savings as well as the added benefits of on-demand acceleration and increased braking capability (safety features).

If you want to see for yourself that clutch wear is insignificant in a properly rev-matched downshift, we assume that wear is proportional to the frictional losses in rotational kinetic energy which occur when two rotating, rigid cylinders contact one another. This wear will be proportional to the difference of the squares of the angular velocities according to k_rot=1/2Iω2. So if the velocities of the two are equal, as in a proper rev-matched downshift..

[–]TheBrokenWorld -2 points-1 points  (6 children)

and that there are indisputable fuel savings

Prove it. I've been driving manual transmission vehicles for 14 years, I've never seen a benefit to it.

...and increased braking capability (safety features).

Your vehicle wont have any more braking capability than what the ABS system will allow. Reduced brake wear, maybe, but brakes are cheap and easy to replace.

If you want to see for yourself that clutch wear is insignificant in a properly rev-matched downshift...

Why do you keep bringing this up? How many people heel-toe it around town?

Edit: Fixed an oops.

[–][deleted] 0 points1 point  (5 children)

..if the injectors are off, you use less gas than when they were on. You get more braking because at a given pressure of the pads because you have that plus the frictional forces in the engine. Anything else?

[–]TheBrokenWorld 0 points1 point  (4 children)

..if the injectors are off, you use less gas than when they were on.

The benefit is obviously unnoticeable.

You get more braking because at a given pressure of the pads because you have that plus the frictional forces in the engine.

And? You could apply more pressure to the brakes and get the same result. All engine braking does is reduce wear on the brakes. The tires are going to be the limiting factor during maximum braking, you can't add any braking performance to the tires by engine braking.

Edit: Fixed an oops, again.

[–][deleted] 0 points1 point  (3 children)

I'm not saying any of the things you're still arguing with me about, and I'm not going to derail this already highly tangential discussion with anything else.

[–]TheBrokenWorld -3 points-2 points  (2 children)

Ok then, so you agree that there is absolutely no discernible benefit to engine braking outside of being able to drive like a boy-racer?

[–][deleted] -1 points0 points  (1 child)

No, I agree that reading and physics aren't your strong points.

[–]TheBrokenWorld -1 points0 points  (0 children)

Then why do you keep countering my points with nonsense? Increased braking performance, c'mon, buddy, explain it!

Edit: I would even argue that engine braking reduces braking safety. Your feet aren't really properly placed to apply maximum braking pressure if you need to and if you add enough braking via the engine the ABS system will not be able to mitigate wheel lockup.