Finally added the EV mod

[Danny Hamilton]

[quote=figmentor @ Jun 5 2007, 11:48 AM) [snapback]455749[/snapback]</div>

For what it's worth, I just took my EV switch out! I am trying anything possible to get my mileage over about 43 including new tires, Mobil 1, 42/40 tire pressure (despite the extra wear that nobody talks about), the block heater and pulse and glide practice. 35,000 miles and I've only done better than 45 a few times. Maybe it's the place I live and all these %^$$ stop lights and short trips. If there are any hypermilers within 100 miles of Lansing, MI, let me know so I can come visit you for a roadtrip, PLEASE!!! contact me at figmentor@yahoo.com
[/b]

Approaching 5,000 on my ODO and have been driving for several weeks now. You can see my average MPG in my sig. I can't tell you why your struggling to exceed 45mpg (possible reasons include average trip distance, average speed, number of stops in average trip, acceleration rate, decceleration rate, average amount of coasting, average amount of gliding, etc). I can however tell you what I do to get the FE that I get.


Original Integrity Tires] 41/39 (extra wear? They are rated for 44 I think?),
Dino oil that came with the car (haven't had first oil change yet, going to before 5,000 like the manual says.)
I have the EV mod installed for entertainment and demonstration purposes only. When I installed it I tried to improve my milage by figureing out when to use it, but after reading many posts here about it, and seeing that my average milage didn't improve much overall, I decided I'd probably hurt my milage more than help it. So now it's just for fun.

I always leave the windows up, and use the auto A/C at the warmest temp I can be comfortable (depends on how sunny it is, but usually somewhere between 68deg. and 78deg.)

No other MPG affecting mods.

My commute is 45 miles each way.
In the morning it is 0.75 miles at 25mph to the first stop light. By that time the car is warmed up enough to shut the engine off when I stop. I get <25MPG for this leg.

I then have 40mph for 2 miles with 1 stop sign and 2 stop lights. I accelerate with the pedal about 1/3 of they way down to 40mph and then set cruise control after each sign and light. I cancel cruise control about 0.25 miles before each stop and try to glide for about 0.125 miles and coast for as much of the remaining 0.125 miles before each stop as I can until a light touch on the brake will stop the car in time. By the end of this leg the MFD reads around 25 to 30MPG depending on how many lights I catch, how well I glide, how accurately I predict my coasting distance, and how much traffic is backed up at the signs.

I then have expressway travel exactly at the speed limit of 55mph for 40 miles (a few short stretches the speed limit gets up to 65mph, but the distances are a small percentage of the trip). I accelerate up the entrance ramp to 55mph using the same approximately 1/3 accelerator pedal as previously and again set cruise control. My destination is a few hundred feet higher than home, and the trip is largely flat (I-80, I-55, I-355, and I-88) with long stretches of very gradual inclines and declines. By the end of this leg the MFD is reading anywhere between 45mpg and 63mpg depending on wind, rain, temperaure, sunshine, how frequently a truck drives in front of me, etc. (but most typically the MFD reads between 53MPG and 58MPG).

I cancel cruise control and coast up the exit ramp where I use just enough accelerator to maintain the 35mph speed limit at the top of the ramp. At this time the SOC is usually all green. I have 5 lights and about 1.25 miles to my destination. About 0.125 miles are at a speed limit of 35mph and the remaining 1.125 miles are at 45mph I try to accelerate from any light I catch at a rate the prvents the ICE from starting up and keep my speed on the 45mph at 41mph. However, if there is any traffic behind me, I match my acceleration to the car next to me, and keep my speed at 45mph. This leg is almost entirely down a very slight decline and I can frequently make it into a parking spot without the ICE starting up and with only losing enough SOC to drop to the top blue bar. This boosts my MPG a bit since I travel 1 mile using essentially 0 gal.

My return trip follows the same route in reverse using the same techniqes except that my trip to the expressway is only about 0.25 miles with 2 lights rather than 1.125 miles with 5 lights.

This is how I accomplish my MPG. YMMV

Note that if my trips averaged less than 6 miles I'd never average 50MPG using these techniques, considering I'm only at 30MPG best case after 2.75 miles, and unless the remaining 3.25 miles were down a continuously steep enough hill to glide the whole way, there wouldn't be enough distance at >50MPG to make up for the 2.75 miles at 30MPG.

I hope this helps explain one way >50MPG can be accomplished, and helps you figure out ways to improve your milage.

This is not a competition. Your temp, wind speeds, precipitation, hills, and average trip length will determine an upper limit for MPG that you can achieve and that may or may not be >50MPG. The challenge is to control what you can to get as close to your upper limit as possible without endangering yourself or others and without enduring more inconvienience than you are willing to.

Some MPG related things you have a lot of control over are your route, your top speed, your acceleration rate, your deceleration rate, how early before a stop you get off the accelerator, how much gliding you do, how well you time stop signs and stop lights, your use of A/C and other power drains, external modifications that increase drag (roof racks, rear bicycle racks, open windows, front end cover, etc), your tires and inflation within certain parameters, perhaps your choice of oil.

If you feel you have adjusted all these to the extent that you are willing or able, and if your car is in good condition and not in need of any repairs, then you are likely getting GREAT MPG no matter what the number is, and most other cars would likely also get significantly worse than their EPA numbers as well under the conditions you are dealing with.

If you don't find this post helpful, I hope a nearby hypermiler has the time to help you make any adjustments to your driving and vehicle that might get you to any goal you have in mind, or at least that they cen help you understand how high MPG can be expected given your particular conditions.

[Pegasus_]

I just added the EV button to my new Prius and am now going to wait until I finish with this (nearly full) tank before using it extensively to see if there's any difference in average MPG.

My plan is to use it when accelerating from nearly every stop instead of babying the pedal (when that will tick off people behind me,) and to use it when the system won't let me glide at lower speeds in the earlier warmup stage(s). The rationale is that electric motors are WAY more efficient than ICEs overall, so to force the car to use its most efficient power source during its least efficient operation (acceleration) should yield at least a noticable MPG increase.

Later I plan to add a charger so I can charge the HV battery to nearly 100% from the wall. This in conjunction with judicious use of the EV mode should make an appreciable difference. (The system favors electric motor use more and more as the battery charge goes up from 5 bars. To maximize this, I would want to use EV mode as much as I can at the end of my trips so the SOC is as low as possible so more charge comes from the wall instead of the ICE.)

Whacha tink?

[Fibb222]

The single biggest thing that makes my mileage higher than it otherwise has to be is short trips. If I drive for only ten minutes many times a tankful, I get ~20% more consumption. That's a big problem that's hard to overcome. Short trips use less gas overall but more gas per mile. I definitely try to plan my routes/errands so that the engine is warmed up as much as possible before I make my first stop.

If I don't have any short trips I consistently get ~4.6 L/100km a tank or 51 mpg US.

I recently installed the EV mod from Coastal and it works fine - I'm on my first tank with it and have currently 4.4 L/100km (54 mpg US) at ~200 km

I know that if I use it incorrectly it will increase my car's fuel consumption. I only plan to use it in situations like the OP described - where a series of traffic lights are strung close together and are often red ; or when leaving my neighborhood which is a few blocks from the freeway. Once I'm on the freeway I'm going down a large hill so I can easily replenish my battery.

I also don't like the ICE coming on shortly after starting up the car when I can't get moving into traffic right away. I prefer to get moving before I let the car heat up the cat converter, hoping this doesn't lead to too many unnecessary emissions, considering that I'm babying the accelerator then.

Lastly, of course, the EV is good in parking lots but it's only necessary then when the car is cold. Otherwise the ICE is almost always off there anyway.

Cheers

[JimboK]

<div class='quotetop'>QUOTE(Pegasus_ @ Jul 5 2007, 01:30 PM) [snapback]473538[/snapback]</div>

I just added the EV button to my new Prius and am now going to wait until I finish with this (nearly full) tank before using it extensively to see if there's any difference in average MPG.

My plan is to use it when accelerating from nearly every stop instead of babying the pedal (when that will tick off people behind me,) and to use it when the system won't let me glide at lower speeds in the earlier warmup stage(s). The rationale is that electric motors are WAY more efficient than ICEs overall, so to force the car to use its most efficient power source during its least efficient operation (acceleration) should yield at least a noticable MPG increase.

Later I plan to add a charger so I can charge the HV battery to nearly 100% from the wall. This in conjunction with judicious use of the EV mode should make an appreciable difference. (The system favors electric motor use more and more as the battery charge goes up from 5 bars. To maximize this, I would want to use EV mode as much as I can at the end of my trips so the SOC is as low as possible so more charge comes from the wall instead of the ICE.)

Whacha tink? [/b]

Hello, Pegasus. Sorry I missed your post when you first wrote it.

For using it during warmup glides, I think you're on target. That's my most frequent use. For accelerating from every stop, the experts would probably tell you that's not wise. I'm not an expert and I may not be describing this precisely, but I think it goes something like this: Yes, the electric motor is more efficient than the ICE. But the battery that powers it is not getting its energy from the grid; it all comes from the ICE. So to recover that lost charge, not only does the ICE run, conversion losses occur as it charges the battery and the battery runs the motor. The EV switch is most helpful keeping the ICE from running when the car needs little or no propulsion.

As for charging it from the grid, I can't speak to that other than to say the car intentionally babies the battery to keep it from even approaching overcharging, in the interest of battery longevity. I'd think if the battery could handle it, Toyota engineers would have allowed it. That presumably is why those who do plug-in conversions add batteries.

[Pegasus_]

<div class='quotetop'>QUOTE(JimboK @ Jul 8 2007, 06:47 PM) [snapback]475217[/snapback]</div>

The EV switch is most helpful keeping the ICE from running when the car needs little or no propulsion.[/b]

...Which makes me think Toyota could have done better with the algorithms. If I was designing them, I'd want to give preference to the electric motor (ESPECIALLY during acceleration, which means using the motor's full potential (momentary 200% torque)) and use the ICE more for generation rather than propulsion (i.e. make it behave more like a series hybrid.) It seems Toyota's focus was more on emissions than fuel economy (which makes a difference as evidenced by the system's running the engine just to keep the exhaust system warm. I wonder if they considered electrically heating the cat converters?) Cost I'm sure was also a factor, since allowing the motor to do what it's capable of would drain the battery pretty quickly and a larger battery costs more.

As for charging it from the grid, I can't speak to that other than to say the car intentionally babies the battery to keep it from even approaching overcharging, in the interest of battery longevity. I'd think if the battery could handle it, Toyota engineers would have allowed it. That presumably is why those who do plug-in conversions add batteries.
[/b]

Actually, they add batteries to get an acceptable all-electric range. The stock battery is only good for 2 miles or so even if used fully. However, it can definitely handle larger cycles (see the Toyota RAV4 EV which uses similar NiMH batteries,) with some decrease in cycle life. But if the current algorithms allow the battery to last >200K miles, why not be more agressive with the fuel economy if it meant even only 100K miles when replacement is <$2000? At 4 cents/mi including grid power, you're still saving over gas! I'm sure Toyota just wasn't taking _any_ chances with the battery so as to offer the long warranty and not lose money or face on it.

[Pegasus_]

Gas mileage improvement:

I recently filled up and have to take my wife downtown three days this week. The good thing is that I can operate in all-electric mode just about the entire time I'm downtown (2 mi roundtrip from the on/off ramp.) My MFD shows just under 60MPG as a result!

Here's what I do:
1) EV mode until I get to a longer stretch (.5mi) when I can let the engine warm itself while moving the whole time (~30MPG)
2) Regular mode onto the highway for about 10 mins, pulsing & gliding sortof the whole way (charges the battery back up by the time I have to exit.) Doing 60-70MPH. 35~99 inst. MPG depending on hills, probably ~52MPG avg.
3) Exit, hit the EV switch when stopped at the light. Accelerate gently with traffic through 7 more lights & 3 turns, etc. 99.9MPG.
4) Kill EV on a longer stretch (.25 mi) nearing the highway (charge up a bit) ~35MPG.
5) Start EV again to accelerate onto the highway until >34MPH when it kills itself.
6) Recharge while P&G-ing back home.

(For San Antonians, I get off IH-35 N at Durango, hit EV switch at that light. L on Flores, R on Houston, R on St. Mary's, L on College, L on the next street, L onto Houston again, L onto Flores, kill EV after Commerce to get a bit more charge (~1.2mi EV at this point), start EV at Durango, R on Durango, L on Pecos La Trinidad back onto IH-35 S.)

P&G makes the most MPG difference. I find that the car's accel pedal is more of a torque than speed control. That is, if you've gotten to your desired speed and the engine is still revving (& MPG is <45,) back off the pedal completely, then press it a bit again. (It seems the computer needs to be told to reevaluate the gear ratio and this is how you tell it.) You'll notice the MPG shoot up to >50 and your speed will stay about the same. This applies on the highway as well as in stop & go traffic. (You just won't glide on the highway as easily since the engine has to spin.)

[bustagriggs]

<div class='quotetop'>QUOTE(JimboK @ Jul 8 2007, 07:47 PM) [snapback]475217[/snapback]</div>

Yes, the electric motor is more efficient than the ICE. But the battery that powers it is not getting its energy from the grid; it all comes from the ICE. So to recover that lost charge, not only does the ICE run, conversion losses occur as it charges the battery and the battery runs the motor. The EV switch is most helpful keeping the ICE from running when the car needs little or no propulsion.
[/b]

I think this is the key part most people don't understand. The electric motor is recharged by gas and just a little by regen braking. The conversion from gas to electric is not 100% efficient. So unless you drive downhill both ways or are very heavy on the gas pedal (causing regen), using electric is a net loss.

The computer may be smart enough to know how much electricity was generated by everything other than ICE and let you use only that much battery and maybe a little more for warm up and anything else that would make the ICE more efficient..

[JimboK]

For the sake of completeness here, I am posting to report that I replaced the switch this week with this, a slightly more expensive ($2.69) and hopefully more rugged switch than the original one. Since shortly after the original installation I have had repeated problems with EV mode spontaneously misfiring. A discussion in this thread helped me focus on the switch as the likely culprit. The problem mostly has been very episodic, too infrequent to overcome my laziness enough to want to fix it. But it recently has been occurring multiple times daily and finally has gotten frustrating enough to replace it.

Here is the finished installation:



I didn't particularly care for the conspicuous red color, but I like the feel of the button. It should be especially helpful in the winter when I'm trying to find it by feel and push it with heavy gloves on.

And most important, the EV misfires have stopped, so I'm declaring the problem resolved.

[Green Hokie]

Hi Jim,

Looks like a button to fire a missile or detonate something!

[JimboK]

Originally Posted by Green Hokie

Looks like a button to fire a missile or detonate something!

Hey, Pete. Long time, no talk-to!

Yeah, I commented in the other thread that I could have some fun with it when my friends ask, "What's that?"

Here's Doc Willie's response to that:

Originally Posted by Doc Willie

"Never touch that button."

"Why not?"

"When pressed, it causes this section of the roof to detach, and the passenger seat to be ejected upward."

"You're joking."

"I never joke about my work, 007"