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Worrying about Auto Stop/Start? Don't!

9.1K views 84 replies 34 participants last post by  996mk2  
I would be surprised if Toyota managed to outsmart physics.

Every time the engine stops, the lubrication film collapses because there is no movement of parts. No movement, no wear.

Every time the engine starts, the lubrication film needs to be build up which takes time. During that time your tribo contacts such as sliding bearings see some wear because they have to travel in the Stribeck curve from its far left end (metal-to-metal contact = wear) over the mid range of the curve (where only few asperities touch each other) to eventually end up in a wear-free zone on the right end of the curve (hydrodnamic area where only the oil sees friction or shear).

This can be mitigated by reducing the overall number of engine starts, regardless if cold or hot.

Under identical running conditions, a brand new engine operates a bit more to the left on the Stribeck curve than the same engine after the proper break-in period.

View attachment 70596
They have special bearing designed for Stop Start systems.
I cannot find the full article i was renemberi g from many years, but this was analyzed in details.
 
I think we'd all be in much better shape if traffic lights were better coordinated than if we had this stop/start stuff. Seems like a no brainer to network the lights to allow much better traffic flow. I believe there is some coordination between some lights that are very close together but there is much more opportunity here I think.
Its a common thing in Europe, I thought you have the same.
In cities, lights are in network, and there are induction sensors in the asphalt, measuring the traffic. In some places it works very good.
 
^this!! +1000000 for roundabouts!!! A tiny slice of tight cornering, chicaneing on an otherwise mundane drive to work. Now if only everyone understood how to use them.....
it can be bad when they don't use their turn signal for exiting. You just wait, wait, and @ssholes just exit next to you without signaling and you cannot just fly through. I love roundabouts but only works if everyone plays by the rule.
 
[.. Entering a roundabout requires a signal.

Well, another law that's clear as mud. 😆
This is unbelievable stupid 😀 the only way you can go when you wait to enter the roundabout is the flow of the traffic . Why on earth you would need to signal entering?

Exiting is the most important to signal as you are giving time to the next person to speed up, when waiting to enter. Otherwise they must wait until the non signaling car exists.
 
I agree that exiting is the most important.
But on entry is also helpful. In the UK we are (were) taught to do both.
A lot of roundabouts are small and don’t have any more than a painted circle in the middle. In those cases it helps me as an oncoming driver anticipate your intent.
On multi-lane roundabouts it lets me know if you are staying to the outside lane and going straight off, or if you are going to the inside lane to go off at a later exit.
Ah, inside the multi lane roundabout is valid!