[changzuki]

11 Points to Ponder (especially #11)....

Using the course at the Green Grand Prix with its turns, hills, and traffic, or, using your own vehicle and driving conditions, let's look at some items that have been mentioned and think for a moment the effect they can have on fuel economy versus a complete clone (or not clone) that hasn't or can't take advantage of the following:

1) Lightweight where possible, including rotating mass. What's it worth in fuel savings while driving with varied, mixed conditions?

2) Aerodynamics - in the case of Centurion vs Centurion there are differences (windshield rake, ground effects, and underside). Aerodynamic differences in two clones - what's it worth? In the case of Centurion vs normal car - what's its small frontal area worth?

3) Drivetrain - again, in the case of Centurion vs Centurion both achieve 65 mph but there are stark differences in drivetrain methodology even though the agreement is on lowering rpm. But we've each tailored our drivetrains for the task at hand (urban driving vs more rural & highway). What is a more efficient drivetrain worth in fuel savings?

4) Fuel shut off - Governor behavior didn't seem clearly understood so I gave an example and a video clip. Being able to effectively shut fuel off to the combustion chambers "at will" - what might that be worth in fuel savings?

5) Decompressor - if you've never experienced the compression release while coasting, well - it's amazing! Releasing cylinder compression with potential to use the rotating mass of the engine - what's it worth in fuel savings? Anything?

6) An engine that's in it's perfect published bsfc range - roughly 80% loaded vs one that is not. what's it worth in efficiency / fuel savings?

7) Gas vs Diesel - from the btu angle. Any fuel savings there?

8) Air to fuel ratio - in discussions throughout the boards it appears that lean-burn is a desirable quality (setting emissions aside which is debatable). In terms of lean burn, a diesel "is" as long as it's not "rolling coal".. What's the lean burn worth in say fuel savings?

9) A driver who knows his/her vehicle - Each person who is driving a car has the ability to raise or lower their mpg on demand regardless of all the current technology. Initially, I learned to drive vehicles by the seat of the pants. Then for years, I learned on a human-dyno using a computrainer. Next came a scangage, and this was on both gas and diesel engined vehicles. Each had their own best practices to turn in great numbers, and so does Centurion. What are these driver applied strategies worth if done correctly?

10) Minimal electrical load - Eliminating alternator load has benefits especially when the engine is small and of limited power. This allows for more of the power it makes to be available, or reduces the load on the engine however one wishes to look at it. Centurion, the Listeroid, and Changzuki do not need electricity to run. Without the drag on the engine of some mechanism to create electricity, what's that worth in fuel savings?

11) ***A specific purpose-built vehicle vs one that is not. This point is huge and typically overlooked. Only a small handful of cars at the GGP (and around) are purpose-built for exceptional mpg. What is a specific purpose-built vehicle for high mpg worth vs one that is not?

There are enough examples above to ponder between any two identical vehicles, or between two different vehicles and what the overall effect will have on something like MPG.

The next logical step is to then put the items from above into practice to see if they work as predicted and make any adjustments/omissions as necessary.

Pulling a personal mpg best, or setting a record at an event like the Green Grand Prix is not a mystery, or looking for some magical alternatives to explain a high mpg run. It's a series of well thought out best practices that were put into a real world working example. (Now there's a quote!)

I think everyone that achieves personal best mpg's (be it at home or at an event) may agree with the above statement. And those ecomodders that did well at this year's Green Grand Prix, quite frankly had their act together, but that's just my observation.

Lastly, when you hear stuff like "so-and-so used every trick in the book", please keep an open mind... Records were made to be broken and occasionally are.

When this happens, "every trick in the book" - just got rewrote..

~CrazyJerry
.

.