Honda Insight w/Acura TSX engine - Ecomodding

[California98Civic]

Originally Posted by MetroMPG

... just saw you have one of the top comments on the article, Ecky. Nicely done.

Your comment, Ecky, really could have been part of the article. My favorite comment be the guy who wrote "shut up and take my star" all IN CAPS. Haha.

[rmay635703]

Originally Posted by California98Civic

Your comment, Ecky, really could have been part of the article. My favorite comment be the guy who wrote "shut up and take my star" all IN CAPS. Haha.

What is the deal with that I can remove as many stars as I want but ???

[Ecky]

Finished cleaning up my low speed fuel maps and built my cam angle tables for low speed (subject to change).




Angles marked in red are for throttle response and power, chosen for their ability to stuff the maximum amount of air into the cylinder.

Black are transition cells, or those basically unused.

Those marked in green are where the majority of steady state driving happens. High cam advance in those areas drastically reduces power output - in some areas 33% or more - because (I believe) the intake cam opens early enough that it prevents some of the exhaust gasses from going out through the exhaust. In other words, a lot of EGR. This should raise cylinder pressure with gasses that don't contain oxygen and pull gasses back in which have heat (usable energy) which hasn't been extracted yet. It should also reduce vacuum in the intake, raising load and moving the engine closer to optimal BSFC. The downside to a lot of EGR is that in more extreme cases I might have to pull timing to avoid detonation from the extra heat, which could negatively affect economy.

Soon the area marked in green will become my lean burn window, which may mean I might have to get rid of the crazy cam advance there. Lean burn requires significantly more ignition advance because the flame front is slower, and the leaner you go, the sooner you have to start combustion, otherwise the piston will race down the cylinder ahead of the slower explosion with no energy extracted at all.

My plan is to lean out to maybe 18.5:1 or 19:1, put a small load on the engine (maybe run the A/C), hold the throttle very still at a specific RPM (let's say 2250RPM), and in real-time advance the ignition timing 0.5 degrees at a time. Every time I advance timing, if power increases (meaning more energy is getting extracted from the combustion event) I should see a small increase in RPM. I'll keep doing this until I stop seeing improvement from adding timing, then back off a few degrees, and that should be close to optimal ignition timing in that rough area of the map for that air-fuel ratio.

[Ecky]

Starting to see returns on my tuning - last tank was ~45mpg, rather than ~40. Not great, but not terrible for what it is, and considering I still don't have a 6th gear.

Currently on my radar are:

0) Lean burn tuning.

1) Get the evap system working - I have RSX, Insight and Accord EGR valves to choose from. The RSX valve does not fit onto my Accord throttle body, and the hose size it uses is smaller than what's in the car, but it matches the ECU and wiring harness. The Insight and Accord valves both have the correct hose size. Once I get the valve plumbed in, I need to move all of the currently orphaned pins on the Insight body harness related to the evap system to their correct places on the RSX ECU.

2) Get cruise control working. Currently I need to add a relay to the brake switch (to break continuity and disable cruise when brake is pressed) and then test - it's probably ready to go otherwise.

3) Finish air conditioning wiring.

4) Get coolant temperature gauge working.

5) I was looking at wiring diagrams and found the pin that goes from the Insight ECU to cluster and carries whatever signaling is needed for the FCD (fuel consumption display) to work, but still don't know what it carries. I plan to play with this (maybe ground it out and see if anything happens) but I doubt I'll get the FCD working accurately any time soon. In the mean time, I ordered a ScanGauge-E from the Ecomodder store.

I don't think the ScanGauge will be able to take into account lean burn though?

[California98Civic]

Originally Posted by Ecky

... I don't think the ScanGauge will be able to take into account lean burn though?

I think that's right. The lean burn guys usually create an MPGino.

[mpg_numbers_guy]

I wonder how the OEM Insight gauges compensated for lean burn? Maybe something can be tapped into to make the Scangauge work, some kind of custom xGauge maybe.

But at that point a MPGuino would be better as it's known to work.

[MakitaDiesel]

1. What are your parameters in Kpro to fool the A/C to cy le? To be clear, you ran a wire from Insight A27 to RSX B9 (AND Insight A17 to RSX E18?) as well for this to work?

2. Do you happen to have a shot of your shifter box where it mounts to the tunnel? Insight/Accord bolt patterns are not the same.

3. I admire your readiness to tune your own car. What resources are you using as guides for this process? I'll either learn it myself or e-tune but I'm doubtful your average outsourced tuner would accept or understand the request of a tune with "lean-burn part-throttle cruise".

Mak

[Ecky]

Originally Posted by MakitaDiesel

1. What are your parameters in Kpro to fool the A/C to cy le? To be clear, you ran a wire from Insight A27 to RSX B9 (AND Insight A17 to RSX E18?) as well for this to work?

2. Do you happen to have a shot of your shifter box where it mounts to the tunnel? Insight/Accord bolt patterns are not the same.

3. I admire your readiness to tune your own car. What resources are you using as guides for this process? I'll either learn it myself or e-tune but I'm doubtful your average outsourced tuner would accept or understand the request of a tune with "lean-burn part-throttle cruise".

Mak

1. I think KPro is supposed to have logic for A/C compensation already, but it didn't work on mine. I'm still playing with, but idle is managed with ignition timing, so if you too find the built-in logic isn't working, you might try having two NOS triggers - one to activate the compressor, and another to add maybe 7 degrees of timing while the car is in the idle range, to "catch" the engine when a sudden load hits. The ECU will adjust timing by itself and stabilize RPM after a moment, just need to give it a small bit of help in the transition.

2) After work.

3) Asking questions on Facebook, reading KPro documentation, following Julian Edgar's lean burn tuning on the stock engine.

[Ecky]

My RE92s on the front wheels are rapidly turning into slicks, so I ordered a pair of wheels for the front. I'm going to try Vredestein Quatrac 5's in 185/60r14. The RE92s in the rear still look almost new.

Why these?

-Low (but not lowest) rolling resistance - probably not as good as Bridgestone or Michelin's best but they're well-regarded

-Middle of the road tread life - moderately sticky rubber that won't need to be replaced too often

-Extremely lightweight - 14lbs for 185 width tires, whereas the stock tires are 13lbs

-They have an option in 165/65r14 for the rears, if I like them

-185 width in the front will close some of the inner track width difference between front and rear track, which should reduce tramlining

-Priced right - $55 for 165's and $75 for 185's

-Rave reviews

I've come to realize, especially after getting fuel maps and cam angles sorted out, that a tire with as little grip as the RE92s are just going to get destroyed by this engine, even if I'm careful.

Since I have proper winter tires, it isn't necessary that I picked out something with great snow traction. All else being equal, I'd have traded a bit of winter handling for most anything else, but these tires seem like a very good compromise of characteristics.

[MetroMPG]

Originally Posted by mpg_numbers_guy

I wonder how the OEM Insight gauges compensated for lean burn? Maybe something can be tapped into to make the Scangauge work, some kind of custom xGauge maybe.

But at that point a MPGuino would be better as it's known to work.

The factory gauges and MPGuino measure fuel use directly (injector pulse activity... I assume the factory gauge does the same), whereas the ScanGauge calculates it based on air consumption, at an assumed 14.7:1 ratio (or thereabouts).



Unfortunately, there's no way to add an x-gauge that calculates MPG in an engine that switches between lean burn and normal stoichiometric.



MPGuino is the way to go.