Lean Burn all the way!

[basjoos]

Originally Posted by greasemonkee

Ahhh, yes, Ireland! perhaps they weren't so emissions restricted? If you find out the code I may be compelled to find one myself, so you may be able to achieve more than 20 hp according to what you're saying.

37820-P07-g01

[steffen707]

Originally Posted by basjoos

37820-P07-g01

According to PGMFI.ORG - Grassroots ECU Development - Library . EcuDefinitionCodes you have one of 2 JDM ecus with the p07-g01 code.

I'm not exactly sure what that means, but apparently there were 2 types of the p07-g01. Perhaps there are different tunes on the eeprom.

My next question is whether or not you can just flash an eeprom with the p07-g01 BIN from that website, and throw it in a USDM 49 state ecu.

I'll have to join pgmfi.org and find out. Its been a long time since i posted on that site.

[greasemonkee]

To my knowledge the P07 code has yet to be understood; there are two eproms within. By now someone may have figured out how to at least socket one of those things, but as far as altering the component commanding it to switch between the leanburn map and normal map - may be impossible.

The only hope would be to put that particular ecu and car on the treadmill and log air/fuel and timing data, add an eprom emulator on a socket friendly ecu and tune based off the recorded data. Even still, you'd only be able to run closed loop on your "leanburn" secondary maps you've created in the software, primary maps would have to run open loop, but for stoich operation this is sufficient. All tuning software I am aware of isn't very economy minded so you'd have to get creative.

I'd love to try this, and if successful burn the maps to a chip which could be used in any VX coupled with a modified ecu and wideband UEGO controller.

BUT, what about egr? Now you've got an whole new variable, and how to control it??? Is it essential for the safe operation of the engine? Lot of time and money to gamble.

[wagonef8]

I run two different tunes on my project car with Neptune I was thinking of doing the same and make a FE tune and a normal tune and just monitor AFR with wideband
HRTuning - Home Of The NepTune RTP and TunerView

[steffen707]

Originally Posted by greasemonkee

To my knowledge the P07 code has yet to be understood; there are two eproms within. By now someone may have figured out how to at least socket one of those things, but as far as altering the component commanding it to switch between the leanburn map and normal map - may be impossible.

The only hope would be to put that particular ecu and car on the treadmill and log air/fuel and timing data, add an eprom emulator on a socket friendly ecu and tune based off the recorded data. Even still, you'd only be able to run closed loop on your "leanburn" secondary maps you've created in the software, primary maps would have to run open loop, but for stoich operation this is sufficient. All tuning software I am aware of isn't very economy minded so you'd have to get creative.

I'd love to try this, and if successful burn the maps to a chip which could be used in any VX coupled with a modified ecu and wideband UEGO controller.

BUT, what about egr? Now you've got an whole new variable, and how to control it??? Is it essential for the safe operation of the engine? Lot of time and money to gamble.

So there's actually 2 eeproms inside each ecu? I called Hondata and they don't do anything with the P07 ecus. No interest in fuel economy there. I did see a p07-g02 for sale in the UK, but it would cost $130 shipped. I don't wanna spend that kind of money to just test and see if I get better MPG when the ecu plugs might not even be the same.

[greasemonkee]

I see we think alike lol. I was eying that one myself and was thinking hard about grabbing it. The P07 is still a mystery then, especially with its wideband LAF controller. Only the P07 has dual eproms - one solely for leanburn and the other for stoichiometric/WOT burn.

Lately I've been wondering if there's any merit in the idea of a MAP hack/piggyback such as a VAFC to force the ecu to stay in leanburn at slightly higher loads. If I can locate one cheap enough I'll give it a shot; another 5 ft/lb torque may go a long way. At this point we're on the verge of throttleless diesel-like operation

[steffen707]

Originally Posted by greasemonkee

Lately I've been wondering if there's any merit in the idea of a MAP hack/piggyback such as a VAFC to force the ecu to stay in leanburn at slightly higher loads. If I can locate one cheap enough I'll give it a shot; another 5 ft/lb torque may go a long way. At this point we're on the verge of throttleless diesel-like operation

I like the possibilities of tweaking stuff, but i'm also worried about screwing up the motor. I don't really feel like having to rebuild it if I end up messing it up.

That's why I like the idea of just an ecu swap, should be easy and maybe in the UK, or japan they had different parameters for when lean burn happens.

Keep me posted on what you discover greasemonkee. I'm sure several would be interested.

[brucepick]

Originally Posted by steffen707

That's odd, in the VX it has to be under like 2400 or 2800, not OVER. Is this right?

Correction to my earlier post saying my '97 HX needs 2400-2500 rpm or better for lean burn. Since Jan. 2012 have been adding Marvel Mystery Oil to the gas and have regularly had lean burn down to about 46 mph in 5th gear which is well below 2400 rpm. Something like 2000 rpm but I never ID'd the lower rpms limiit for lean burn. You can see my thread http://ecomodder.com/forum/showthrea...oil-21024.html.