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WOT?.....I NEVER go past 34% TPS.
Wasn't the Insight deliberately engineered to utilize the upper throttle range efficiently? If not it seems like it was - you know, high gear, low RPM, command electric but not see a gas penalty... I like to do that, probably mostly because I'm in perpetual pack-testing mode. Provided I can regen the electric when I would have otherwise been wasting the momentum, I can't say that I miss much... I can't say that I gain much either - except the 'thrill' of raw NiMH power... To me there's something really cool about super low RPM but having all that power available...
 

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Discussion Starter #83 (Edited)
@eq1:
I read something you said about that like 6 months ago, and I have tried every now and then to take advantage of flooring it right after an upshift at the shift indicator light. I do typically drive for FE though, so I'm not always sure how to work this in because you are still burning more gas. My pack is like okay though, it's not an incredible one, so maybe if I had a Bumblebee battery or something I'd be able to get more out of it.

The guys on Ecomodder who get 100mpg with their Insights usually talk about staying in lean burn almost the entire time the engine is running. I'm not sure how much assist they can even get like that. It might be that the car's maximum efficiency can be attained WITHOUT an IMA battery and its added weight, going by how they're driving. But I suspect most Insight drivers are looking for a balance between turtle mode hypermiling and "normal" driving with power//acceleration as needed.
 

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Yeah, I'm not going for Hyper-miler Grand Poo-bah status. One can clearly get better fuel economy driving slow and not using the IMA. But I like using the electric - going pretty fast but still getting good fuel economy...

I just took a drive that I do quite often, about 40 miles, mostly county highways and back roads. I got 85 mpg (actually the highest ever; it's usually like 78 mpg, and previous highest was 83) - yet I was still using a lot of assist, doing the speed limit+, and doing a handful of near full-throttle accelerations. Over the last ~4 years I've averaged about 67 mpg. I can't really complain with these numbers. That average is 2.5 times what I used to get in a first gen Miata...

But anyhow, you do need a decent pack to use high throttle levels effectively. I could never do what I do now with my previous clunker packs...
 

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What is your charging strategy? Do you grid charge between runs? Do you have MIMA? Do you drain it low enough to get background charge?

I seem to worry more about not having to charge than using a lot of assist. I use MIMA to get extra charge under deceleration and to add assist going uphill so I can stay in lean burn. I FAS a LOT on downhills, but coast in gear if I need to charge.

Sam
 

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What is your charging strategy? Do you grid charge between runs? Do you have MIMA? Do you drain it low enough to get background charge?
No grid charge, mima. Background charge doesn't seem to depend on how low I go, so I don't know. If I have lights on it comes on around 65%, otherwise it comes on whenever it feels like it... Charging strategy is to charge when it's convenient or I absolutely have to. I'll let it background charge if I'm on flats, I don't worry about that. I'll delay background charge if I know I'll have a good down hill coming up... Um, I always graze the brake pedal for full regen when coming to stops, rarely need to use brake friction material...
 

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Discussion Starter #87 (Edited)
There is a new development!

Note: I'm not driving the same car anymore, I'm now driving a 2000 red Insight with LTO. It has all aero panels, bottom has been smoothed out, OEM rims with RE92s at 60 PSI, rear wiper delete, and full lower grille block.

Anyway, what I have learned recently is that at moderate to low highway speeds, so say 40mph through about 55 mph, if I am going up a slight incline, and 5th gear + lean burn at 75 or 80 MPG instant FCD is not cutting it and the car is starting to decelerate, what I learned is 4th gear lean burn in the 55 to 70 MPG instant FCD can actually push the car up the hill and not lose speed!

This is better than dropping out of lean burn and staying in 5th and using assist to get up the same hill.

Is this potentially the purpose behind the otherwise overlooked and sometimes maligned 4th gear? I've noticed that when doing this below 50% SOC I sometimes even get some background charge in the 5-7 amp range and the car stays around 60 or 65 MPG instant FCD while in lean burn and it doesn't slow down. It's like there's a sweet spot or something.

I have of course hundreds of times used 4th gear to get up hills at speed, I just had never thought to attempt to do it in lean burn and to push the FCD below 75 MPG instant while doing so. In 5th gear the limit for lean burn seems to be around 75 MPG instant on the FCD -- push the pedal down any more and it will go back to stoichiometric burn, but the 4th gear lean burn limit is lower on the FCD, but still HIGHER MPGs than 5th gear + assist stoichiometric burn according to the instant FCD.

A couple guys made posts pointing me in this direction earlier in this thread, but I think I just didn't quite understand the instructions at the time.
 

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My experience and methods are similar. The car just doesn't have much climbing ability in 5th. If you are trying to get the optimal MPG and still maintain speed, you may just have to downshift. You just have to make a grade judgment and gear choice at each hill. Some gentle hills, when the air isn't dense, tires pumped up, etc. the car will climb and loose little speed. Unfortunately, since the purge cycle is load related, you may loose LB half way up.

I find that when I'm faced with downshifting to 4th, I need to do it a bit early so that I can re-establish LB before I start climbing. That is much easier than trying to get back into LB after one is already climbing.
 

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When mine is in lean burn, I can shift up or down without taking my foot off the gas and maintain lean burn. Don’t your cars do that?
 

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Discussion Starter #91
If I shift from 5th to 4th it will pop out of lean burn for about 1 second and then go back in as long as I hold the accelerator steady (so this is not ideal because I would prefer to blip it to rev-match) and as long as I wasn't near the limit of 5th gear lean burn accelerator depression (near 75 or 80 MPG on the instant FCD)
 

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When mine is in lean burn, I can shift up or down without taking my foot off the gas and maintain lean burn. Don’t your cars do that?
I was curious and just test drove my 2006 to see if it would do this. On several downshifts from 5th to 4th, I could not achieve this behavior. I did notice that the OBDII C&C green light does linger a second or so on clutching, but I don't slam downshifts, so I didn't manage to achieve the no LB gap. It might differ if it were warmer here or if the tires were at higher pressure.
 

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I agree – that's why I have the brick size sponge under my gas pedal for better calibrated foot pedal control.

The precision of where the gas pedal needs to be is greatly enhanced with the sponge .I know it sounds wacko But it works. it's my personal throttle position sensor.

In my heated gasoline line regulated with orifice or a needle valve keeps my car at the 150 mpg FCD most of the time. Cost under $40 to do it. With stop and g0es driving back-and-forth to work at 50 mph I'm getting over 100 mpg. But Highway only 150 MPG at 50 mph .

I never use 4th gear going up the highway to climb hills.

I think I am burning less gas in the motor so the air ratio goes up. The car is not continuously flooded with Un oxidized gasoline. To me it's a type of turbo charged. More air than fuel . And I can cut the fuel back even more and not have enough power to climb hills it's all in the needle valve adjustment.

I think when more gas enters the motor then it can burn it's flooded everyone is used to it don't realize it's happening. So you have slightly more power when you do it the way I'm doing it to climb hills. It takes practically no gas at all to go on level. Or 150 mpg at 50 mph.

Or you could say it's just another Monday
 

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I was curious and just test drove my 2006 to see if it would do this. On several downshifts from 5th to 4th, I could not achieve this behavior. I did notice that the OBDII C&C green light does linger a second or so on clutching, but I don't slam downshifts, so I didn't manage to achieve the no LB gap. It might differ if it were warmer here or if the tires were at higher pressure.
I was testing tonight, just to be sure I wasn’t fibbing. On a flat road, at about 45 to 55 mph, I can go from 4th to 5th and keep lean burn. I didn’t have the road to test it at higher speeds. It’s just above freezing, wet roads, tires are at 35 psi. 10 mph slower and I can do the same between 3rd and 4th. I can’t quite get 3, 4, and 5 to do it all at once due to bouncing or lagging at either end. I’m not feathering the clutch or slamming, either. In-shift-out over the course of a couple seconds.

Curious.
 

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Yes, seemingly so, but I learn something every day. May have something to do with electronic box versions. So, Natalya reported she couldn't do it and I can't. Maybe we'll get some others to weigh in :)
 

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I'm pretty sure that I lose LB for a short time when I shift, either up or down. But I really don't pay that close attention.

Sam
 

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Yes, seemingly so, but I learn something every day. May have something to do with electronic box versions. So, Natalya reported she couldn't do it and I can't. Maybe we'll get some others to weigh in :)
I went out again today in calm weather, dry, flat roads, temps around freezing, same tire pressure as before. At 55 I can shift between 3, 4, and 5 with no loss of lean burn. I can do the same at 35 mph. It’s easier going up gear than down and upper gears give better mileage. 75 mpg low, 100 mpg high. My speed remains constant. I tried down-shifting 4-3 at the bottom of a pretty good rise, 20+ feet and fairly steep, and sailed over it in 3rd, still in lean burn, at the same speed (45 mph), with the up-shift light on. I suppose I could use the technique to up my lifetime, but I’m not that obsessed with it.

Now, keep in mind that this car sometimes, but very rarely, slides into autostop at 25mph. Not sure if the two are related, but thought it might be worth mentioning.
 

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I assume you are using the FCD as an indication of "Lean Burn"?
 

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I have.an ammeter in series with my LAF sensor to indicate lean burn, and I can fairly readily move between gears in which lean burn should be possible if I keep the gas steady. Only tried it a little but not hitting the clutch switch at the bottom of travel seemed to make it more reliable... Or maybe not. Also tried once to go from fourth to third and LB was lost, but came right back when I went back to fourth.
 

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