SGII Driving Lessons

[trikkonceptz]

OK finally got my SGII up and running, now come the questions ...

I understand open/closed loop and throttle position. Now how do I use them to my full advantage? Can I accelerate to speed with as high a TP as possible without going open loop and still expect to increase FE. Or is slow steady acceleration the norm for automatics?

[Daox]

The higher the engine load (LOD) the better. Load is not directly proportional to TPS which is why I like to use it instead of TPS.

[trikkonceptz]

Originally Posted by Daox

The higher the engine load (LOD) the better. Load is not directly proportional to TPS which is why I like to use it instead of TPS.

Please explain LOD, I am not familiar with that term or how to monitor it.

[Daox]

Engine load is basically the % of maximum torque you are using at a said rpm.

[trikkonceptz]

OK got it ... now how do I use that with my scangauge and to my advantage?

[dleefoto]

How can the LOD gauge (if not, then what gauge?) tell you when your engine begins fuel enrichment, or when it goes out of closed loop?

[Arragonis]

Originally Posted by Daox

Engine load is basically the % of maximum torque you are using at a said rpm.

Genuine question and not having a go, but how does it know what the maximum available torque is, and how does it know what torque you are using when modern cars have such different torque curves ?

Example - Honda Civic Type R (headline 192hp hatchback) has max torque at 5600 rpm (only 142 lb/ft - ), mine has it at 1900 (229 lb/ft ) or around 290+ lb/ft chipped .

I'm intrigued by the LOD measure. I'm tempted to use it but it remains a mystery. I know there is wisdom there, somewhere.

[Daox]

Allow me to answer your question with a question. How does an engine know how much fuel to inject? It calculates it based off the amount of air flowing into the engine. It knows the maximum amount of air it can let in (for the most part, there is compensation for air density etc so LOD isn't 100% exact), and it knows the minimum amount of air. Calculating percentage is a small step away then.

[euromodder]

Originally Posted by Arragonis

I'm intrigued by the LOD measure. I'm tempted to use it but it remains a mystery.

It's one of my permanent gauges, and it does give a good indication of how hard the engine is working.
Yesterday however, it was jumping from 30 to 55 while I was doing 100kph on the motorway @ 67+ mpg (HM would see a lofty 81 mpg).

[Arragonis]

Originally Posted by Daox

Allow me to answer your question with a question. How does an engine know how much fuel to inject? It calculates it based off the amount of air flowing into the engine. It knows the maximum amount of air it can let in (for the most part, there is compensation for air density etc so LOD isn't 100% exact), and it knows the minimum amount of air. Calculating percentage is a small step away then.

On my Diesel it will be a lookup value in a table based on factors like engine speed, temp, throttle position and air flow. But I still wonder how it knows what the max is to work out how much of it you are using.

To amplify a little. To work out % torque you would need to know for the current engine speed how much torque your engine can make at max, and then how much you are making now.

Or is it just fuel load, how much fuel is being added compared to how much could be added ?