Braking...

Here's my thoughts on my Prius appliance:

- Its braking is nowhere as good as the Civic or Insight braking
- In the Honda system, the first half-inch is reserved exclusively for electrical braking. If you want friction braking, move your foot greater than 1/2 an inch & it engages the disc brakes. Release your foot and it releases the disc brakes (but electric braking is still active).
- The prius is not that simple.

In my prius I have yet to figure out the magic amount to push my foot, so I can activate electrical braking without touching the friction brakes.

 

The Prius is really easy and good. The right 3/4 of the brake area in the HSI is regeneration. That will do almost all of the braking you need and does not use the friction brakes. That may or may not be some amount of push from your foot. Its sort of like you use the speedometer to find out how fast you are going, not your hand out the window to feel the wind

 

My take, if you never use B mode, stay in D, you'll be in the best mode virtually all the time.

The only time I ever get the urge to use B is coming down one of our ski hills. Even though it's likely warranted in that situation, it really gets on my nerves: the high revs sound like the engine's protesting. I use it sparingly even in that scenario.

 

Hate to wear down my brake pads just because the engine revs.

 

It's B mode that makes the engine rev.

 

I know it's B mode that does this. I was just wondering if B mode harms anything.

Not to mention, can you damage anything by driving while in B mode, i.e.:foot on gas. Yes, I foot a couple of times

 

Back in the old days when I was driving a 1940 Chevy dump truck the boss said "Its cheaper to replace the brakes than the engine." I suspect that doesn't relate to this situation The 1941 truck had vacuum assist brakes... wow!

 

I haven't been doing very well at reading the manual for much more than the basics, so I'm thankful for these posts that explain things like the braking. I understand regen, etc., but I thought there was always friction braking when the pedal was depressed, so I'll now change some of my driving habits. I already slow down approaching stops, etc., but I'll slow down even more when I can.

 

I actually dislike using B down a long grade. Shifting from D to B will start the gas engine, thus wasting fuel and putting unnecessary wear on the engine components. Wouldn't it be better to stay in D and let the engine shut off?

 

B mode does not use any fuel when coasting downhill - the engine just pumps air.

 

Going down a hill in B, the car shuts off fuel to the engine then spins the engine to provide drag and thus slow the car.

Wear should be negligible as the duration is short and loads are much less than in normal running as there there is no fuel and thus none of the high pressures and high forces associated with fuel combustion.

 

Engine wear in B mode is equal to the number of miles driven * 1.5 (because the rpm is approximately 1.5 more than normal). I don't see why hybrids need a B mode. Perhaps if the hill is extremely steep, but hybrids absorb the downhill energy through the electric motor. That keeps the disc brakes cooler.

 

Number of revolutions is not the only factor in wear.

B is for big hills where regeneration has to stop because the battery is full so without engine braking, all you would have is friction braking.

Its a significant benefit in particular circumstances and costs almost nothing to implement.