mmrmnhrm Posted June 10, 2006 Report Share Posted June 10, 2006 New question from the noob... Over on the GH boards, we're having a bit of a debate on just how to get the best accelleration profile out of our hybrids without flat-out flooring the thing (which is pretty sad, considering we've only got, at best, 110hp). The tree hugging crowd is all about doing it as slowly as possible, to the point where someone cracked a joke about a granny with a walker asking if they needed a push. The practical crowd (me included) prefers to just get going, but don't really care to just floor the thing, either. One of the folks brought up an interesting point: Why not just find the best rpm/power range, and use that. Seems straightforward enough, but we've got two problems... one, how to remove the effect of the electric motors coupled to our engines, and two, how does one find the engine output with a continuously variable transmission? The sites I've checked out so far all seem to imply that getting a good run depends on having total control over what gear the engine is running in. With a CVT, that's pretty much impossible. Quote Link to comment Share on other sites More sharing options...
Buteo Posted June 10, 2006 Report Share Posted June 10, 2006 i dont think hybrids were intended to be put on a dyno? Quote Link to comment Share on other sites More sharing options...
mmrmnhrm Posted June 11, 2006 Author Report Share Posted June 11, 2006 Almost certainly not It was more a theoretical question, given that I still haven't been able to think of a way to decouple electric from gasoline without the thing throwing all sorts of malfunction lights. I do know the Hondas *can* run on gasoline only, which is something the Toyotas can't do. Quote Link to comment Share on other sites More sharing options...
Nate1647545505 Posted June 11, 2006 Report Share Posted June 11, 2006 As far as the gasoline side max efficiency is lowest brake specific fuel consumption, and is measureable on a dyno with fuel flow and horsepwer data. The electronic side is probably measured in somewhat of the smae matter, except you measure efficiency with volt/hp. With a CVT, one would think Toyota would put both the electric motor and gasoline motor in prime efficiency ratings, they would be wasting money if they didn't. Quote Link to comment Share on other sites More sharing options...
Mensan Posted June 11, 2006 Report Share Posted June 11, 2006 With a CVT, one would think Toyota would put both the electric motor and gasoline motor in prime efficiency ratings, they would be wasting money if they didn't. Unless they couldn't compromise on efficiency vs. power. If it's best efficiency comes at an RPM where no power is made, the car would be a dog, and people would complain. Also, you would measure current/hp, the voltage will be static. Chris, if you want to get more fuel efficiency, let me know. I think we could get 10 more mpg easy out of that car, maybe much more. Quote Link to comment Share on other sites More sharing options...
mmrmnhrm Posted June 11, 2006 Author Report Share Posted June 11, 2006 Nate: If only that were the case... Honda's programming tends to leave the rpm a little on the high side in order to encourage recharging of the battery pack. This is more pronounced using cruise control, which is a little annoying. I can usually beat the computer cruise control by using foot cruise control, especially on hills. Eli: I'm also pretty sure there's more to be squeezed out of this engine. If the "early adopters" report good news, I'll be switching the stock paper air filter with a K&N, and the tires have already been raised to 44psi (max sidewall) instead of the OEM 32psi. A couple of folks have been looking into adding a CAI, but the engine compartment is so cramped I don't know where they're going to find the space for the pipe leading to the airbox. Similar problems were reported by folks who looked into changing the cat-back. Oil will also be changed from Honda's break-in to Mobil1 Group2 synth in another 5k miles or so. Honda's 0W20 is apparently only a semi-synthetic, and the M1 is the only other option at this weight right now. It be nice if there were a group 1, but nobody else is making one yet. Quote Link to comment Share on other sites More sharing options...
Nate1647545505 Posted June 11, 2006 Report Share Posted June 11, 2006 Unless they couldn't compromise on efficiency vs. power. If it's best efficiency comes at an RPM where no power is made, the car would be a dog, and people would complain. Also, you would measure current/hp, the voltage will be static. Chris, if you want to get more fuel efficiency, let me know. I think we could get 10 more mpg easy out of that car, maybe much more. Ah yes, sorry bout that. Usually electric motors are most efficient at 75%-100% of their max speed (guess it's all relative to motor, windings, casing, etc) We all could get more MPG out of our engine's, but we wouldn't exactly be helping the environment Eli, I know you mentioned something about extracting more power out of the hybrids, what is in that brain of yours? Quote Link to comment Share on other sites More sharing options...
mmrmnhrm Posted June 12, 2006 Author Report Share Posted June 12, 2006 Aha! Seems the work has already been done, it just took someone with press hookups to find it. So here's the chart: http://hondanews.com/media_storage/GIF/S2_Civic_10.gif (Link to full article) If I'm reading this correctly, the combined torque of electric+gas is just a hair over 120ft-lb up through about 2800rpm, at which point it starts tailing off, probably because the electric motor's controller can't rotate between windings fast enough. The 'Engine only' lines also cross right around 2800rpm, though I need you guys to speculate on whether this is just coincidence, or actually meaningful. Could it be related to the "throttle body fully open at 2650rpm" theory I related earlier? At any rate, since the torque starts dropping off there, and is flat before that, I suspect that means anywhere in the first 2800rpm will be more or less equal in terms of fuel efficiency (so long as granny doesn't cheat and give the treehuggers a push), while anything past that is great for jumping in front of trucks, but otherwise silly (especially when going against someone with a real engine ). Quote Link to comment Share on other sites More sharing options...
mmrmnhrm Posted June 12, 2006 Author Report Share Posted June 12, 2006 We all could get more MPG out of our engine's, but we wouldn't exactly be helping the environment Talking about burning lean here? IIRC, the Insight actually gets zero tax credit because even though its mpg rating is way up, and CO2 emissions miniscule, the NOx is atrocious. Quote Link to comment Share on other sites More sharing options...
mmrmnhrm Posted June 17, 2006 Author Report Share Posted June 17, 2006 Theories? Anyone? Quote Link to comment Share on other sites More sharing options...
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