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Old 05-07-2012, 11:34 AM   #15 (permalink)
itjstagame
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Join Date: Sep 2008
Location: Thomaston, CT
Posts: 23

Commuter Plus - '98 Saturn SW2
Last 3: 37.12 mpg (US)

Rover - '07 Land Rover LR3 HSE
Last 3: 17.6 mpg (US)

Blackie - '16 Ford Focus Titanium Hatchback
90 day: 33.25 mpg (US)

Bertha - '11 Four Winds Chateau 31a
90 day: 7.79 mpg (US)

Van - '15 Honda Odyssey EX
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Yes I knew the numbers were pretty useless, I don't really have the time to do ABA testing as I don't get home until almost 7pm most nights and weekends are always busy, so I do what I can and log what I can. Again this wasn't to show the outcome of a lab test really, I was experimenting to see if it was even worth considering somekind of ABA test or if it was even useful. As shown it didn't even make sense to attempt ram air and even if the numbers aren't controlled enough to prove one way or another, I think it's pretty clearly it was the wrong thing to attempt. I think a lot of people start with experiments, see if it 'feels' better and then do and ABA to prove whether it is or not.

I know I didn't include weather conditions but can you think of anything that would cause a 6mpg drop? I think that is fairly significant, but like I said the numbers don't matter as much to me as I could tell by watching the gauges that FE dropped and so did power.

I do understand the point between warm air and cold air and yes I now see what you mean, about the ram air. Increasing pressure would require less throttle opening and therefore more pumping losses (or equal losses since the point is at less throttle we should have same vacuum/pressure/oxygen as before without 'ram'). It would only work without a throttle restriction, so at WOT or in a diesel (which has no throttle plate), in which case increased pressure would decrease pumping losses. I guess I fell in to the 'less throttle is good' and completely forgot the point of my WAI.

That said, it may still have a use (if it worked) just as CAI can have a point. Anything that can increase the efficiency of my 60-70% throttle pulse should be useful since otherwise my engine should be off anyway.

That said, I always wish I had a gauge like MPG/s or something so I can find for a given acceleration or power output what is the most efficient. For instance, maybe 4th gear at 4-5krpm on the DOHC is actually more efficient than 70% throttle at 2k rpm in 5th gear. I'm not sure, but the point would be even though 4th gear clearly gives worse MPG, it should really just be what uses the least fuel to pulse from 50-60mph. So if higher rpm was more efficient; then even if it got half the MPG as pulsing in 5th it should take LESS than half the time. Again, we can read about BSFC for a given engine, but I wish I could think of some gauge or some test to show in a given environment installed in a car what the most efficient acceleration is.
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