Alt kill switch planning (help)

[Ladogaboy]

Originally Posted by California98Civic

Though longterm fuel trim was somewhat rich, 0.78 going out and 1.56 coming back...

Lambda, I'm assuming? I usually deal with ratios, so I have to calculate.

[California98Civic]

Originally Posted by Ladogaboy

Lambda, I'm assuming? I usually deal with ratios, so I have to calculate.

I'm not sure how to answer directly, not fuly understanding what lambda is for this context. The numbers I reported are the UltraGauge, which represents lean or rich as +/- percentages. For example the +0.78 I reported indicates rich conditions and if I had seen say for example -3.06 I would be looking at a lean percentage. Does that mean 0.00 is "lambda"?

[brucepick]

Originally Posted by California98Civic

"GPES", I like it. It effectively makes a simple ICE into a crude and practical hybrid, you know? I hardly ever charge my charging system with anything other than the grid. The power I used for the 65 mile trip home yesterday came entirely from the solar panels my friend has on his house roof. Much greener than burning gasoline.

One optional addition to the "GPES" mod would be electrical load reductions (LED, HID, and such...). With load reductions I have driven my commuting distances in the cold dark without using the alternator at all. Your plans are even more promising for night driving because of the bigger deep cycle batteries you are considering.

james

Electrical load reductions would definitely be a worthwhile component of a GPES.

[EDIT]
On second thought (investigation), the concept is already covered, briefly, in the Master List of 65+ proven mods, under Alternator Delete...
http://ecomodder.com/forum/fuel-econ...ications.php#5

[Ladogaboy]

Originally Posted by California98Civic

I'm not sure how to answer directly, not fuly understanding what lambda is for this context. The numbers I reported are the UltraGauge, which represents lean or rich as +/- percentages. For example the +0.78 I reported indicates rich conditions and if I had seen say for example -3.06 I would be looking at a lean percentage. Does that mean 0.00 is "lambda"?

As I understand it, 1 = Lambda (or stoich... 14.7:1 AFR). So yes, < 1 means rich, and > 1 means lean.

[California98Civic]

Originally Posted by Ladogaboy

As I understand it, 1 = Lambda (or stoich... 14.7:1 AFR). So yes, < 1 means rich, and > 1 means lean.

So then, this would mean that a +1.56% rich condition as counted by the Ultra Gauge is 1.0156 and +0.78% is 1.0078?

[Ladogaboy]

No, 1 Lambda = stoich/14.7:1 AFR, so .9 Lambda = 13.23:1 AFR. Likewise, 1.1 Lambda = 16.17:1 AFR.

This is my understanding, anyway.

[California98Civic]

Originally Posted by Ladogaboy

No, 1 Lambda = stoich/14.7:1 AFR, so .9 Lambda = 13.23:1 AFR. Likewise, 1.1 Lambda = 16.17:1 AFR.

Thanks! Your comments sent me back to the UltraGauge user manual and I learned something. In my earlier posts I had it backwards as to what the UG numbers mean. Quoting the manual: "positive values indicate a lean condition exists and the injector is left open longer to compensate, thus adding more fuel" (p.17). Now that means that a UG reading of +1.56% long term fuel trim is 1.0156 lambda, a lean condition, and my car will add more fuel to maintain stoich? That's not good for fuel economy. Better would be negative percentages, indicating rich condition, in response to which the car's ECU will seek stoich by reducing fuel.

Do I have that right?

[Ladogaboy]

I'm not sure how the UG is listing it... that's why I was asking. Maybe someone else on these boards can explain? But your explanation sounds viable.

[3dplane]

Originally Posted by California98Civic

"positive values indicate a lean condition exists and the injector is left open longer to compensate, thus adding more fuel" (p.17). Now that means that a UG reading of +1.56% long term fuel trim is 1.0156 lambda, a lean condition, and my car will add more fuel to maintain stoich? That's not good for fuel economy. Better would be negative percentages, indicating rich condition, in response to which the car's ECU will seek stoich by reducing fuel.

Do I have that right?

Ideally you want to see near zero % fuel trim values on a properly operating system.
Neither rich or lean is good. Positive values indicate a lean condition as the ECU is trying to compensate for that. It is still a lean condition! Same true vica versa if it is running rich and the ECU is reducing fuel and you see the negative values, you STILL have a rich condition!

When the ECU has to exceed it's predetermined range/limit of allowed compensation in either direction,that's when you get a check engine light with the appropriate code.

(On GM vehicles I believe it is around 25% long term fuel trim value.)

Barna

[brucepick]

Originally Posted by brucepick

Electrical load reductions would definitely be a worthwhile component of a GPES.

[EDIT]
On second thought (investigation), the concept is already covered, briefly, in the Master List of 65+ proven mods, under Alternator Delete...
65+ Vehicle modifications for better fuel economy - EcoModder.com

On my earlier suggestion to rename "Alternator Delete" to "Grid Powered Electrical System" or GPES - - -

On third thought (fourth? fifth??), somehow the term "Alternator Delete" conjures up images of home town drag strip runs. True that the item in the "65 mods" thread did mention the other critical component, the deep cycle battery.

I think we should call it EPES, for Externally Powered Electrical System. "Grid Powered..." or GPES doesn't include solar. "Externally Powered Electrical System" states what's really being done, and hints at its most significant feature: you're no longer getting electricity by burning gasoline in the engine.

Projects like these go way beyond a simple deletion of the alternator. In fact the alt often remains in place, with the belt in place also.

I think there's a case to be made that it deserves a more descriptive name when you combine a disabled alternator plus a carefully selected deep cycle battery, plus a charger, plus wiring and switching to enable the use of the alt when wanted. And maybe even wiring and switching to enable the use of two separate batteries as needed, to make the system more flexible and more capable.

I suggest EPES, for Externally Powered Electrical System.