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Filter the throttle position sensor's signal - a smoother signal to the ECU keeps it in lean-burn longer. Might this work on the HCH-I as well?

http://autospeed.com/cms/A_110187/article.html

Hi Andrew:

___I can see how it might help a new driver but a good Insight driver is already driving to keep TPS output as smooth as possible. Look at the std. traces and let me know if any of the heavy hitters drive an Insight like this in DWL steady state cruise. P&G is a different story where the smoothing circuit could actually harm but in a steady state cruise, his numbers are to low by comparison to what has been achieved in the real world during steady state cruise.

___Just my opinion but the circuit does not extend lean-burn, it just helps those with a heavy foot maintain a smoother TPS input into the ECU and the Insight will not drop out nearly as quickly.

___Since you will be in Plano this weekend, Reid or Chuck will let you drive theirs and you will see what is going on when the iFCD is running at 125 + mpg at 35- 40 mph and how you can control it. Above 55 mpg however, lean-burn is there but FE is disappearing quickly :(

___It was interesting to see a > 25:1 A/F ratio however? I thought 22.7 or so :1 was about the peak even though the LAF can read upwards of 25:1?

___Good Luck

___Wayne

In the Insight, I find myself watching the iMPG rather than the speedo (which can cause problems!). I modulate throttle position to keep the iMPG where I want it, and sometimes find myself going slower (or faster) than I meant to go.

As xcel says, the Insight is a real good throttle-foot-trainer.

Is it more sensitive than the Prius and HCH-II? I found them to be very sensitive compared to my older civic.

I agree with Wayne's assessment. He was driving pretty fast and I get better results with just my foot.

The Insight is about as sensitive as the HCH-I, a little more than the HCH-II (which seems a bit more forgiving at lower RPMs). The feel is similar though -- you hit a number and really need to make fine adjustments with your foot to get changes that don't vary pretty wildly.

Is it more sensitive than the Prius and HCH-II? I found them to be very sensitive compared to my older civic.

I don't know because I've never driven either the Prius or the HCH (sure wish I could!). But the Insight does seem to have a very delicate throttle - to the point where it seems to be affected by the driver's mood!

I've read Autospeed for years now. Great site with good articles. Also, they seem to be turning with the market and going more green. All the better IMO. So, I read their latest article on a modification that aims to keep you in lean burn mode easier than normal on the highway. I'm no expert on lean burn, but I do understand how the mod works. Interesting mod I thought would be useful to share considering theres some pretty hardcore Insighters around here. :)

http://autospeed.com/cms/A_110187/article.html

A fellow Insighter, sent me the link to this article, and was asking if I thought it had any merits for a hypermiler, or if we were/could do the same manually. I have not responded to him personlly as of yet, but....

IIRC the conversion is 235dot215, which would give ~81mpgUS, for the driver/vehicle in the article? I have seen some of that this winter, and I feel like I should pull back the hammer on the six gun when exiting the Insight.

Those that have asked the Insight to teach them how to drive it for maximizing the FE, have adjusted their right foot control to do pretty much what the TP smoother mod has done, like Wayne has said. I can see where it might help the heavy footed.

Not to take this off topic, but I am getting to the point of offense at the term "real world mileage", etc..etc., such as the tone in the article. It would seem that 3 years of daily commutes, sprinkled with road trips for Christmas, Hybridfest, picking up family at distant airports, is not real world. :confused:

I too was fasinated with the 25:1 AFR:eek:

Randall

Looks like Autospeed has un-subscription-ized a lot of their
articles recently.
.
_H*

I'd like to hear what others think of this modification. What's the downside? Are there any components that could be harmed by running lean for an over-extended period?

Haha, I missed PaleMelanesian's post on this. This thread can be deleted IMO.

So, you Insight drivers never get kicked out of lean burn when you want to stay in it? From the sound of the article it sounds like that can happen fairly easy (and I realize he's no hypermiler). I've never driven one, so I can't really say one way or another.

Moderators Note: Merged threads

Thanks Delta Flyer.

It's pretty unneccessary. I can stay in lean burn for 95% of long highway trips easily with good foot modulation.

As mentioned earlier, I pick the mileage.

The terrain decides how fast I go. :D:D:D

Tim, with foot control the only things that knock me out of lean burn are steep terrain, extra cold temperatures, and low speeds (which I FAS most of the time anyway ;))

Thanks for all the responses. I didn't know how hard/easy it was to maintain lean-burn.