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In a few days I will have another chance to drive a Prius.

Was reading Wayne's thread on P&G. Let's see how good a reader I've been.

Gently get up to your high speed (say 40mph), but not so gentle to do it in EV mode
Slightly let up on the accelerator to glide and avoid regen or the ICE running
When down to the low speed (say 20mph), repeat this againDid I "get it"?

AFAIK you don't just let totally off the throttle. Instead, once you're totally off the throttle, you immediately put ever-so-slight pressure on the pedal again, until the Energy screen shows white arrows going to all components.

Then you hold it there until you drop to your pre-determined speed level.

AFAIK you don't just let totally off the throttle. Instead, once you're totally off the throttle, you immediately put ever-so-slight pressure on the pedal again, until the Energy screen shows white arrows going to all components.

Then you hold it there until you drop to your pre-determined speed level.

Slight correction -- there should be NO arrows, just dark lines implying no power flows. At least if we're talking about the newest generation of Prius. --RN

When you pulse, try to keep the iMPG about half of your speed. Jim K says so, with others supporting that tidbit. Completely let off the throttle and then gently push it back down until you see no arrows. To maximize this, keep your speed under 40 mph. It's also easier once the ICE is warm, of course. A SG showing RPM's would also help. Keep the RPM's in the 1600-2300 range. If a SG isn't available, follow Jim's tip on the pulsing speed.

I hope all of that made sense. If it didn't, I'm sure someone will correct my ramblings. (It's that kind of day already...:eek:)

EDIT: Don't forget to turn it off when you're done. Right Marc?

The kind of day is Friday the 13th :eek:

Seriously, I'm the designated "dummy" on this thread.

What is iMPG?

Instantaneous MPG?

Yep, instantaneous MPG. And no, it's not that kind of Friday 13. It's just super busy.

Hi Chuck:

___With you and Dan car pooling in from Texas, you will have all the time in the world to learn some of the Prius’ secrets. Trust me, you will be an expert before you hit Oklahoma if Dan has anything to say about it :D

___Good Luck

___Wayne

I'm sure Dan will, but want to be as quick a study as possible.

Hi Delta Flyer,

Looks like you've got most of the idea down. :)

- "Pulse" up to target speed (anything 40 or below)
- Let off the accelerator completely to coax the ICE to shut off, and immediately...
- Re-apply light accelerator pressure such that you get no arrows on the energy screen. (green arrows = not enough, yellow arrows = too much)
- Hold this until you get down to your minimum speed
- Repeat!

As already mentioned, you don't need to be too easy with the "pulse" either. More "aggressive" pulsing, such that your IMPG matches or is a little less than your MPH as you accelerate, is fine. You're looking for either red+yellow arrows with no arrows to or from the battery (this is what is referred to as "deadband") or red+green, or even red+yellow+green. What you don't want is drawing current off of the battery (red+yellow, with a yellow arrow from the battery). Let the pulse also do the work of recharging for you. :)

Dan will certainly make you an expert if you are carpooling all the way here. :)

OK.. time for my Highway writeup. Hobbit seems to be the pro at high speed FE, so most of this is just taken from his site.

CC+help is the easiest way and it's what I strive for on the HW. Holding 60mph with the AC at around 77c while cruising at around 57 avg MPH should be achievable.

CC+help is a simple way to use CC as a minimum speed maintainer to give your leg some rest on flats. The way it works is set the CC at around 54 mph (88kph). Now when your in kph you'll get a warning before you hit CC panic. If your CC is set to 88kph then it will panic at 86kph. So this means that 87kph is your red zone. The driver's job is to keep the speed above 87kph and below 95kph while keeping RPM b/t 1400 and 2400 rpm. Highway driving is what first drove me to using KPH, in MPH I didn't know the CC would panic until I heard the engine rev.

So on the flats, if your in control at 90kph and CC is set at 88kph, simply hold the RPM at 1400 which (unless you have a tail wind) will slowly decel the car to 86kph. The CC will panic and jack the RPMs up to about 1800-1900 rpm to recover, then settle back down to about 1500. Now you get to leave it on auto-pilot till you see an incline or decline.

So on the declines. If it's a gradual decline that will have and end to it soon with a flat run, you may just want to take over and hold the RPM at 1400 RPM. When you get to the flat, transition to a stealth-warp till you bleed off enough speed to trigger a CC panic. As long as it panics on a flat, your OK, just let it do it's thing. Now if the decline is followed by an incline, it's a bit tricker. If you think the decline is steep enough, steath-warp down the hill then break out to acel up to around 95kph when you hit the bottom. This should give you enough momentum to cover the incline. On a few occasions I'll charge the slope hitting it at 90-95 kph in preparation for a nice long stealth-warp.

Now for inclines. Basic principle is just learning how much speed a hill will eat. Most over passes around my area will eat 3-5 kph if scaled at 1800 rpm. So I'll usually charge the hill hitting it at 90-95kph so that I can crest it at 88kph. If it's an overpass, they are steep enough to hold speed on the back side, so once I crest I'm in a good position to stealth-warp down the otherside. Once I'm on the flat, my speed bleeds off, CC panics and I'm on auto-pilot.

CC panic. As long as I'm not scaling a hill I'm usually OK with the efficets of the panic and the spike of RPMs. On flats or downhill grades, it never usually goes over 1800, sometimes with a headwind it will hit 2200 rpm. You can minimize the effects of a panic by easing up to the panic zone as gradually as possible. If I see a panic coming on a hill, I just pull back on the stalk, canceling CC. The target speed is still in memory, so it's easy to get back. You can also just reduce (or increase) the target speed with the stalk controls as well.

Autopilot. CC does OK on flats, but if a downhill grade is coming I'll usually P&G down the grade over the CC's control. Problem zone is 1400-1050 rpm. At highway speeds this is the lugging zone, and FE is poor. Looks good on SG, but FCD will not lie. Better to do a HS P&G (using stealth-warp as your glide) than to suffer a long period of lugging. If I see a lug event coming, I'll just get on the gas a bit to keep the RPM at 1400. Once we hit the flats the speed will bleed off and CC will take over.

So CC @ 88kph and max speed set to 95kph usually gives and avg speed of around 57mph.
When I'm in a hurry I set CC to 90kph with a max speed of 100kph, gives an avg just shy of 60mph.

Hobbit, how'd I do?

11011011

Hi Delta Flyer,

Looks like you've got most of the idea down. :)

- "Pulse" up to target speed (anything 40 or below)
- Let off the accelerator completely to coax the ICE to shut off, and immediately...
- Re-apply light accelerator pressure such that you get no arrows on the energy screen. (green arrows = not enough, yellow arrows = too much)
- Hold this until you get down to your minimum speed
- Repeat!

As already mentioned, you don't need to be too easy with the "pulse" either. More "aggressive" pulsing, such that your IMPG matches or is a little less than your MPH as you accelerate, is fine. You're looking for either red+yellow arrows with no arrows to or from the battery (this is what is referred to as "deadband") or red+green, or even red+yellow+green. What you don't want is drawing current off of the battery (red+yellow, with a yellow arrow from the battery). Let the pulse also do the work of recharging for you. :)

Dan will certainly make you an expert if you are carpooling all the way here. :)

Hey guys, in an effort to simplify the P&G how-to, I've got an easier way to do it. I found that the sweet-spot on the throttle was sometimes hard to hit with the AC running and pack down to 3 bars. I didn't realize it at the time, but I'd changed my procedure for entering glides and it had been committed to muscle memory. SG is required.

The mod is to forgo the re-apply and just throw it into neutral. It's actually easier to time than the feathering of the gas. The shifter seems to have about a 200 ms delay worked into the circuit. So work it kinda like a reverse clutch. On a stick, I usually press my foot (clutch) and move the shifter at almost the exact same time. This usually gets me through gears quick. The foot is a bit ahead of the hand to make the timing right.

So if your foot is a bit ahead of your hand and you try to pull off the gas and shift into N at the "same" time you'll fall right into a glide with very little re-gen or EV expended. For me it was just cuz I was lazy and didn't want to hold my foot at the magic spot.

Cool part is this, think this is exactly how you have to P&G the Camry.

11011011

Hi Dan:

___I have only experienced a good bit of Highway in the Prius-I and her 1.5 loves 1,250 – 1,400 RPM. The FE numbers there got stupid but my speeds were in the 47 – 52 mph range, not 55 plus unfortunately. Until I get some real time behind the wheel of a Prius-II on my commute, I may as well be talking about driving to the moon but I bet the lesser powered 1.5 in the Prius-I follows the same fuel consumption maps as the Prius-II?

___Running the TCH into a N-Glide is exactly the way it should be performed ;) Yoshi posted an interesting bit on current flows into or out of MG1 in N above 31 mph in the Prius-II but I am not sure that was a one off or actual on everyone’s. Caution advised until someone gets to the bottom of that issue?

___Good Luck

___Wayne

___Running the TCH into a N-Glide is exactly the way it should be performed ;) Yoshi posted an interesting bit on current flows into or out of MG1 in N above 31 mph in the Prius-II but I am not sure that was a one off or actual on everyone’s. Caution advised until someone gets to the bottom of that issue?:eek:

Yikes

Looks about right to me, Dan ... I'll occasionally use the
CC as a low-limit "reminder" to myself too, but usually take
the main work of RPM regulation manually for most of the
way. On mostly-flats the CC doesn't stray too far if it's
allowed to autopilot, either, but you'll likely peak over
3000 on overpasses and then "loaf" down the backside. I
see that happening, I'm like "gimme that thing, you don't
know what you're doing" as I yank the stalk to cancel.
.
I'm heading for Hybridfest with no particular new wacko
theories on any of this, other than just staying within
1600-2400 or thereabouts and seeing what I can do. Two
grand +/- 400, real easy to remember. I don't see a
significant vacuum drop until > 2400, which I attribute to
a slightly more open throttle, so I figure that's still
within range and will give me that tiny bit more climbing
capability without too much pain. But generally the lower
I can hold within that range and still maintain speed,
the better. I think. I might discover yet more stuff
[after *how* long of owning this thing?!] on this run...
.
_H*