Harlan

iTrader: (3)

Ok, figured it out. The Narrow band o2 was effecting Commanded AFR. Disconnected it and it pulled me down to 14.3 max until it flagged a CEL then I had full control of AFR. Drove a little bit at around 16:1. Need to make a permanent solution if I'm gonna run like this. While lean burning ECTs didn't seem to change, but EGT did go up by about 30 deg.

olddragger

iTrader: (3)

HUH!!! Did you say that the narrow band o2 sensor ( after the CC) had an affect on your a/f????
Are you sure??.
All this time everyone has thought that the narrow bands only real function was to check to see if the CC was working right?

Harlan

iTrader: (3)

100% positive. I was directly offsetting the wideband signal to the ECU, and the Narrow Band was causing the ecu to drop commanded AFRs. With the signal wire pulled from the Narrow band (0volts to ECU or ultra lean.) my commanded AFRs dropped to 14.3 max instead of 14.8. When the ECU registered the NB as a fault AFRs went to 14.8 as usual.

It appears the ECU is using the NB as a go/no go test when at stoich. This had no effect to my ability to lean AFRs at idle, because the ECU expects to see a lean condition. Probably to prevent a lean condition that could cause engine damage.

Harlan

iTrader: (3)

Currently have the car set up to tweak the narrow band, I'll run a data set to show it effecting commanded AFR on my drive to work tomorrow. Currently soaking some fuel injectors to test if they will rust up. I'm starting to think that the problems with running fuel injectors as water injectors goes back to engines designed without ethanol, and doesn't apply to modern (last 15 years) fuel injectors. I'll find out soon. Also I'm starting to understand MM's tuning posts. Dunno if I'm going crazy, need to stop reading the forums, or need to drink more.

Harlan

iTrader: (3)

Small update:

Fuel injectors are still soaking, no adverse effects. Working out a controller with an arduino as well as a mounting location in the UIM.

LS2 coils do not work for an Ion sense application, which I could have figured out by looking at the wiring diagram, but instead I chose to waste an afternoon. I have an Isuzu coil on order and hopefully it has a useable pin for in cylinder pressure.

I have successfully run lean burn, but the results have been less than positive. As I force the ECU to read rich it drives the mixture lean, down to -25% STFT; however it drives my timing back as it reads higher engine load. Need to tweak indicated MAF in order to get this to work and ideally I need a more advanced timing than stock.

Have a 192F thermostat waiting to put it in. Also have some 0W20 oil. I think the 0W20 will be perfect with a zinc additive. These two things are probably going to be the silver bullet where fuel economy is concerned.

May be a while before I update again. My work schedule is kinda hectic right now.

olddragger

iTrader: (3)

ok---need more info.....

Harlan

iTrader: (3)

An arduino is an open source micro controller. Some people have even used them as piggyback ECUs. I'm planning on using mine at first to control water injection and monitor peak combustion pressure.

All ignition timing is based around trying to maintain peak pressure at about 15 deg ATDC or on a rotary about 45 deg ATDC. Sabb pioneered a technology using spark plugs as ionization gap sensors (Ion Sense) to monitor cylinder pressure, and some Isuzus have that technology as well. It's a long shot, but it could get interesting. Sabb even went so far as to have a closed loop ignition timing system. Maybe I've gone off the deep end, but it seems doable to me. If nothing else it has the potential to be a much better knock detection system.
http://g-homeserver.com/attachments/...ortunities.pdf
http://delphi.com/manufacturers/auto...gnsys/ionized/

Harlan

iTrader: (3)

Well got some stuff done this weekend. Changed all my oil to 0w20 with STP oil treatment as well. The 192deg thermostat I had was the right size but did not have the bypass valve on it. So there I am sitting with my car torn apart to get to the dang thermostat and no replacement. So at first I tried shimming an extra thermostat I had. No luck, it seems the wax slug is set for a certain temperature and spring tension has little effect. So in the end I sacrificed a spare motorad thermostat to get the bypass valve to put on my proper setpoint thermostat. The result: Frankenstat.

Also the past week I have slowly been tweeking timing, got it up to 10deg adv above stock in the 3-4k cruise range. Now I have it back at +8 with the higher coolant temps, and plan to keep tweaking it up until I either start to see EGT dropping rapidly or ECT spiking. Spark plugs still look good. Gaining slight ammounts of fuel economy each step. Will try steam injection again with the higher coolant temps.

TomB

I would like to get your thoughts on the water free coolant you are using. I just bought a 2010 RX-8 and plan on changing the coolant. I saw a video on Jay Leno's Garage about using the Evans product and I'm very interested. The only downside I see is the price. looks like about $200 but you never change it again. Will it work well in the RX-8?

Harlan

iTrader: (3)

Evans NPG is great stuff. The concept is valid, and running water free coolant has saved my engine a couple times in the hot Texas heat. It will run a little hotter both because of more efficient heat transfer from less steam blanketing (good) and because the coolant has a lower specific heat (bad). It also has limited nucleate boiling which is bad for heat transfer.

It's not truly lifetime, although if you wanted you could dry it out on a stove when it got too water logged. The PG and EG are both hygroscopic so they will absorb water over time.

As for the expense, I just run straight EG antifreeze (prestone universal). It is thicker than Evans NPG and has a slightly lower specific heat capacity, but it's cheap and it also can save you from coolant seal failure. Hope this helps some.

olddragger

iTrader: (3)

you are running straight EG antifreeze?
Not too thick for the water pump at high rpm?
Concerned about cavitation.

Harlan

iTrader: (3)

With the higher boiling point there is less cavitation not more. It probably kills a couple HP at high rpm, but the water pump does fine. Don't take this as an endorsement for straight EG, just a statement that it works.

longpath

iTrader: (1)

I'm intrigued by your solution for creating a higher than stock thermostat. I'd been thinking of implementing one when I was first looking into Evans waterless coolant. I am using NPG+. My current maintenance strategy is to vent pressure on a dry day when the coolant is cold, then drive it for an hour (my commute is fine for that), then close the cap when I arrive. I figure once or twice a year during a dry winter day is fine for this. I'm curious what thermostat you started out with before altering it to serve here.

Harlan

iTrader: (3)

Drying out the coolant like that works pretty well. I even thought about puting an air breather to vac like the oil reservoir to keep air flowing through it while the engine is running. It should dry out the coolant just like it does the oil.

The higher than stock thermostat was a failure. No significant MPG gains, also made heat soak much worse. Not worth it! Running 0-W20 did gain a little bit of short trip fuel economy, but long highway economy didn't change and I'm sure it's worse for the engine. Sorry I got caught up in other things and never did post results for everything in this thread.

olddragger

iTrader: (3)

I meant cavitation because of the viscosity difference between the coolants. The more vicious a fluid the harder it is for this type of pump to move it. The impeller is moving pretty fast at 8K engine rpms!
Probably not an issue--but i was just curious.

Harlan

iTrader: (3)

Moving a viscous fluid does take more work, but a fluid needs to boil to cavitate. I've watched pumps cavitating pumping 130deg water because the pump was drawing a vacuum at the impeller lowering the boiling point to less than 130degrees. Raise the boiling point of the fluid and you have less cavitation.

olddragger

iTrader: (3)

now that is something I didnt realize---thanks. After thinking about it further your answer makes perfect sense.

longpath

iTrader: (1)

Sorry to hear that it did not pan out; but I thank you for taking the time to try it. I look forward to your results, whenever you can post them.