I'm not going point by point to be a jerk - just don't want to miss something.
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Originally Posted by BigVinnie
Also to Jeff, how do you explain the loss in fuel that needs to be used as PSI increases as well as cylinder temprature? In order to prevent detonation to highly volitile O2 that is being compressed additional fuel is used in the process to actually drop cylinder temp (but I guess you coming from Florida doesn't care to understand how NOX and smog emissions works).
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Loss in fuel? If fuel goes into the combustion chamber, it's combusted. Not lost. So.. due to this glaring mis-wording, I really dont' know what you're talking about.
Cylinder temperature during driving (not on a dyno) isn't changed due to pressure, unless the intercooler is unefficient. Otherwise, I've yet to see a good intercooler fail to regulate charge temp to within 10*F of ambient.
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Fuel actually being heavier and denser than O2 will make it harder to compress.
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Again.. there's a communications breakdown here. You can't compress a liquid. Period. So I dont' know what this is about.
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You can use a lower injection bandwidth at lower RPM, but as you boost higher PSI to make more power the bandwidth will have to increase as the RPM/to power level gets larger, as well as engine temprature.
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This is another Mushmouth-ish bit. I don't know what this is about, but I'll take a shot. First, it's pulsewidth, not bandwidth. And ya, as you raise horsepower, be it by pressure (PSI, as you state), or by natural revs of the motor, the fuel must be added to make said power. Power = Air x Fuel.
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It isn't the fuel saver you say it is when you push your engine into higher RPM's or WOT. If FI engines conserved fuel through out the entire power band then there would defenitely be alot more FI engines on the road (especially with our fuel crisis we have today). Do you ever ask your self why the fuck are there crappy Hybrids?
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This is pretty easy to answer. Hybrids save more fuel than a forced induction setup. And the other side of that is that turbos are too expensive to use for pure fuel economy.
And.. someone else's quote:
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You're not comparing the correct numbers. For this comparison, you need to look at WOT. Your car isn't making anywhere near 300hp when you're not making boost.
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Here's the deal though, I hit boost EVERY time I step on the throttle. I make 2-5psi boost just leaving a stoplight and driving to 3000rpm. I also hit your WOT (zero vacuum) at 2000rpm, EVERY time I step on the throttle.
Myself, and any other random guy driving his car on the street, drive roughly equivalently. I hit 320hp the same number of times he hits 155hp. And, as I accelerate to 3000rpm, I pull 200+hp from 2500-on, at partial throttle. He hits 100hp from 2500-on (or something) at partial throttle.
It doesn't matter about the fact
I don't hit WOT. I hit your WOT without thinking or trying. And.. get better efficiency in the rest of my driving. Think about it - your exhaust gasses are wasted out your exhaust pipe, and your engine works to suck air in. That's why only at WOT and 5k+ rpm you hit zero vacuum. My exhaust gasses spool a turbine, which is attached to the compressor via a propeller shaft. The compressor sucks the air (rather than the engine doing it), and then pushes it into the engine (not compressed during say, highway driving). And, at 2k-onwards, my car is at your WOT (zero vacuum), at partial throttle. Your wasted gasses are put to work on my car, and doing the engine's most important job (being an air pump). You need to understand that I am getting "free" energy that's put to work on my car, and that all else equal, my harnessed exhaust doing something that your exhaust isn't - makes my engine more efficient.
-Jeff