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Old 03-02-2012, 09:32 PM   #4 (permalink)
Olympiadis
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Quote:
Originally Posted by Ken Fry View Post
Hard to know what you are trying to say here. First, given factory optimized timing, (which varies continuously under control of the ECU) a tuner cannot make "drastic" changes in either BSFC or output (which are not the same thing). There are no evil automotive engineers working to make you use more fuel. Companies spend many millions to tune for an optimized mix of fuel economy, drivability and performance.
Obviously the "ads" about HHO you have read with the claims you cite are wrong. You sound as though you're trying hard to convince me and perhaps yourself as well.

If you yourself have done testing on an automotive engine with regard to scale of HHO production vs engine air demand, then I would be curious to see your results, beyond your calculated estimates of course. I have yet to test such a thing and the data may become useful to me in some other area of tuning.

I received a very thorough training concerning the conservation of energy as a sophomore in high-school (1982) which has always been useful to me in many areas of life, not just physics classes.
It is a law that has dominion over all that we know in a broad scope, but when applied to individual situations the caveat "in a closed system" must be applied for it to be fully reconciled in the accounting process.

What I see you doing here is what I have seen numerous times by the younger crowd of freshly trained physicists (not meaning you), and that is to target the alternator of the vehicle as the weak point, having such a poor energy conversion rating. And it's not that it matters if the alternator was in fact 100% efficient, because that was never the point, and I would never get drawn into such a red herring (at least I would hope). If it were a closed system with a 100% efficient alternator, then HHO could still not produce excess energy. As far as I'm concerned that was never worth arguing.
The glaring fact remains that an automotive engine is not a closed system due to the majority of chemical energy in the gasoline not being converted into usable motion.
That is exactly where my discussion of burn-rate comes into play. An improvement in fuel efficiency that comes from a slightly better energy conversion rate in the combustion chamber is completely separate and, depending on tuning specifics, can far outpace the quantity of energy lost to an inefficient charging system, no matter what that power may be used for.

IRT what I quoted from you above, you seem to be confused about how the adaptive spark algorithms are actually working. What makes me think this is that you more than allude to the idea that millions spend by automotive companies directly result in an "optimized mix of fuel economy, drivability and performance.". If what you're really saying is that the tune is a compromise for greatly varying climates and extreme levels of ineptitude by the drivers of the vehicles they sell, then you would be on the right track. Don't forget to throw in the requirement to maintain a specified window of emissions, - that's a big one.
The fact is that the spark advance is not optimized for even running at stoich, let alone a particular performance aspect. Every algorithm I've looked at for adaptive spark starts with one or more base tables that are quite conservative ( in the interest of longevity in the hands of many ), with table switching thresholds and spark modifiers based on feedback from a knock-sensor, - the purpose being to minimize engine damage in a variety of circumstances ranging from bad fuel, to towing, to malfunctions or mechanical issues. I have yet to see an algorithm that is programmed to increase the efficiency of the burn, or result in less fuel used.
If you own a vehicle with such an algorithm, then please post it here. I would find it quite interesting, and I welcome new input.

Also, in the scope of what I've seen personally, the adaptive spark logic and adaptive fuel logic operate separately and completely independently of each other. This precludes the possibility of the ECM/PCM automatically tuning for best economy. An engine tuner has to perform this task of combining feedback from both fuel and spark in order to optimize a tune. I may be wrong, but I feel that if you were a real tuner, then this would already have occurred to you by necessity.
There is also the fact that if the PCM were programmed with logic to optimize best economy, then it would be unable to remain within the specified window of emissions standards.

If you have been around skilled tuners for any amount of time, or in fact learned the skill yourself, then you would also know that the difference a tuner can make is much more significant than you suggest. If there wasn't a significant room for improvement, then what would be the point?

I was amused at your attempted straw-man, being the evil automotive engineers. The ones that are and have been gainfully employed by an automotive company are generally extremely competent and do a great job given the constraints imposed upon them. Let them work unbridled by government imposed regulation and they could surely impress us all.
Change your straw-man to the EPA and I'll bite.
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