Driving to consumption vs. driving to load
 

I keep seeing mention of driving to load, but there are cars like the civic and newer gms that utilize lean burn, and this fuel saving technology is not load specific. I submit that whenever possible, driving to consumption lets you find and stay in lean burn much longer, and thus save more gas. I also found out that mu cruise is configured to stay in lean burn as long as possible.

I agree.

Actually "driving to consumption" is probably a better way of describing what I do when I say I'm "driving with load" (DWL) anyway (even though I don't have lean burn).

I almost never have the "LOD" value displayed on my ScanGauge - when I'm focused on DWL, I'm actually watching instant fuel consumption (MPG).

What newer GM's have lean burn? So far the only documented cars I know of that use it are Honda and some Fords (search for Escort lean burn here).

Ecotecs do it, and some v8s. The u haul truck I rented had it, and do does my ion.

The scan guage II in my 2007 Yaris displays Intake air temp, because I use exhaust manifold heat to heat the intake air, Coolent temperature, Throatle position switch, and LHK Liters per 100km, instintaniouse fuel consumption. The readings I use for FE are TPS and LHK. I have the option of load but never found it helpful because of my poor understanding of how to make it usefull to my driving for FE. When in cruise control on the highway if the TPS goes to 17 with a hint of engine bracking I know I can depress the clutch and coast down the hill at idle without having to tap the brake to kick it out of cruise... When I depress the clutch by mistake before the apropriat conditions prevail what the engine does is raise RPM about 600rmp then stay at that RPM for about 15sec then goes to idle, or it stays at the RPM it was at in cruise for 15seconds then returns to idle. Its interesting what our mestakes teach us...

Holy typos, batman, I use fuel flow in gph to find lean burn, tps is redundant, imo, since you should know where your footy is on the throttle, unless you are looking to avoid, let's say, 80% throttle, but still, gph is your best friend in efficiency hunting, shooting for the lowest flow is ideal

Holy typos, batman, I use fuel flow in gph to find lean burn, tps is redundant, imo, since you should know where your foot is on the throttle, unless you are looking to avoid, let's say, 80% throttle, but still, gph is your best friend in efficiency hunting, shooting for the lowest flow is ideal

Hmm... I was aware that the direct-injection GM engines used lean-burn, but I am not aware of any conventional port-injected GM engines that use lean burn (in North America anyway).

For those of us running stoic, watching MAF flow is also a good indicator, as air-mass is directly proportional to fuel-mass when an engine is in closed loop.

The guy that tuned my engine said it appeared as though my car was going into lean burn.

...look for engines listed as being SIDI (Spark Ignition direct Injection).

Where is it said they have to be direct injection to have lean burn?

The problem with lean burn is NOX emissions. Direct injection allows higher compression on lower quality fuel. It may also allow higher air-fuel ratios without NOX issues. Not sure about that but the higher compression accomplishes the same result without NOX issues.

Many manufacturers tried lean burn a couple of decades ago. The best comparison of the mileage difference would be the Federal and California versions of the Honda Civic VX.

Direct injection cools the in combustion temperature by transferring the heat to the incoming fuel charge for better atomization and higher compression. It may eventually evolve into a real HCCI design which will allow true lean burning with virtually no regulated emissions.

If (or when) they perfect a HCCI IC gasoline engine, the potential elimination of any after combustion treatment of exhaust emissions may actually be a consequence of that evolution of the IC engine. 60% conversion of fuel energy, combined with integrated pulse and glide of the power planet while the vehicle operates independently of the power plants function will produce the proverbial 100 MPG car.

regards
Mech

My car has a 10.1:1 compression ratio. Nothing too special, but high enough. It also earns ulev rating, if not sulev iirc, this is because of many things, but I believe lean burn is one of them. My tuner knows what lean burn looks like, so I trust his judgement.

The previous generation Prius had 13.5 to 1 compression, ran on regular fuel and did not have lean burn.

Lean burn can be easily determined by reading the voltage generated by the O2 sensor.

I don't think your Saturn has lean burn, but it can easily be confirmed by a simple voltage reading.

regards
Mech