FIT Lean Burn

[Veen]

Been perusing lean burn posts a bit lately and trying to figure out if I have a "lean burn" mode in my GE FIT. Any other FIT owners have a lean burn area they like to ride in?

[Xist]

Lean burn is effectively outlawed in the U.S. as of 2005. It reduces carbon emissions, but drastically increases nitride emissions. The First Generation Honda Insight was an Ultra-Low Emissions Vehicle (with a manual transmission), but when the EPA changed the standards it was too dirty to sell. A few users have made their cars burn lean, but that sounds incredibly difficult.

I have lean burn on my Civic and as much as I enjoy getting better fuel economy at 65 than 55, I am not sure I would ever modify a car for lean burn.

The major production vehicles to have lean burn are the old CRX HF, Civic VX and HX, and the first generation Insight, but never a model with an automatic\CVT.

[ar5boosted]

Are there any tutorials for adding an easy* lean-burn to an existing vehicle ?

[cRiPpLe_rOoStEr]

Originally Posted by ar5boosted

Are there any tutorials for adding an easy* lean-burn to an existing vehicle ?

It would usually involve fooling the ECU with a different O² sensor signal. Maybe those emulators used in older CNG conversions could work for that matter, but I'm not sure. Also, that would leave one less room to keep the mixture control accuracy.

[rmay635703]

Originally Posted by Xist

Lean burn is effectively outlawed in the U.S. The First Generation Honda Insight was an Ultra-Low Emissions Vehicle (with a manual transmission), but when the EPA changed the standards it was too dirty to sell. A few usersautomatic\CVT.

That is a myth , the insight met standards but required too costly of a cat

[Xist]

Lean burn is effectively outlawed in the U.S. without an excessively expensive catalytic converter.

You may be able to find more information here: http://ecomodder.com/forum/showthrea...urn-27865.html

[oil pan 4]

Every vehicle is different. If you want to add lean burn you have to remap the fuel trim table.
If you just trick it into lean burn then it runs lean all the time when it shouldn't and you burn valves and at that time it's pretty much get another engine.
I only know because I have been there and done that.
Do not trick your engine into running lean, do it right or pay the price.

[cRiPpLe_rOoStEr]

If you'd be willing to fool the engine to keep longer at lean-burn, maybe it would worth to try either water injection or just a supplemental injector nozzle right after the throttle-body to avoid going too lean at high load (that was quite usual in my country, especially on turbocharged engines).

Originally Posted by oil pan 4

If you just trick it into lean burn then it runs lean all the time when it shouldn't and you burn valves and at that time it's pretty much get another engine.
I only know because I have been there and done that.
Do not trick your engine into running lean, do it right or pay the price.

That reminds me of some misconceptions held against CNG in my country. Since it has a higher compressibility than gasoline or ethanol, many conversions are set to run so lean on CNG that the engine easily overheats, damaging valve seats or even cracking the engine head.