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electric supercharger?b/s or not?

Discussion in 'General Tech and Maintenance' started by luis3360, Feb 16, 2006.

  1. luis3360

    luis3360 Junior Member

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    i have a ? i see i was n ebay looking around for a turbo or supercharger, and i see a mayor
    market of people selling this electrics supercharger offering up to 40 hp\and 1200cfm /
    and useing only 3 amps of your battery,. isit [b/s or not?
     
  2. jamesA

    jamesA Well known pissed off telephone guy VIP

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    Its BS. Don't bother with it.
     
  3. luis3360

    luis3360 Junior Member

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    so its just a m/fkin money making biz
     
  4. Z6CRX

    Z6CRX übber ɐɾuıu etarip

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    only if you use it to blow nitrous [​IMG] .. and even then its not worth it. Spend your money on something more usefull, or hook up a leaferblower to see if it help before you spend your money on some as retarded as this;) .
     
  5. Citizen_Insane

    Citizen_Insane Senior Member

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    Technically you could build an electric supercharger that worked by using a high output motor to spin a turbocharger compressor housing. Not very efficient tho. The whole reason turbo's rock is they recycle the energy from waste exhuast gases and turn it into useful power. Thats why they lead to more efficient engines.

    Also, a "real" electric supercharger would cost more than a DIY turbo setup. In otherwords, don't bother, its a waste of money and time. Just turbo if you want more power.
     
  6. brian11to1

    brian11to1 Senior Member

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  7. luis3360

    luis3360 Junior Member

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    thanks for the advice guys. :) :)
     
  8. Celerity

    Celerity Well-Known Member

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    I think it's time for a Celerity rant. I haven't yapped at ya'all about this in over a year, so I'll do it again.

    Supercharger, Turbo Charger, Electric Charger.

    None is more valid than the other. And here's why:

    A Supercharger has a leeching affect on the driver pulley. We all know that. So, people might say "Yeah, it blows air - but it's also like driving with your A/C on" And in a way, they would be right. But you see the SC adds more power than it leeches because of a few basics that hold true about Superchargers:
    * They blow colder air than a Turbo. Colder air, in essence (Not exact figures) means that 6 psi from a SC is comparable to 8+psi from a turbo. Or 12+ from a turbo without an intercooler (And it better be a free flowing intercooler too)
    * Their pulleys are very low draw, when the clutch isn't engages. Also, a screw-type of charger like an Eaton or Whipple has it's rotating mass very close to the axis of the rotator. This means that it's not like the pulley is turning a big fan.
    * Superchargers build up their pressures in the manifold very quickly.

    Turbochargers are more common because of their cost (Face it, not many moving parts = lower prices). But there is a myth that surrounds them: Turbos are not free power. Repeat after me: There is NO such thing as free power. Turbos build up pressure in the intake manifolds, but they also build up pressures on the exhaust side. It's slight, but it is there. There is a leeching affect that I would say is about the same as a SC (Now wait.. don't flame me out just yet). Any aircraft engineer can tell you that Turbos don't spin up air because of exhaust gasses "blowing" into the vanes - The exhaust air, which is very hot, hits the vanes and instantly cools - This is the biggest part that's overlooked on a turbo. a multi-fin vane is turned somewhat by pressures blowing it and making it spin: But it really produces more air on the intake side of the turbo because the gasses that hit the vanes contract and "pile up" on the vane before being spun around and exited out of the exhaust. That's where a good percentage of your forces are being transduced.

    And before I go on about the Electric "supercharger" I want to address tranduction. Tranducing is when you change one form of energy into another form - Light to electricity is transduction. Heat to air flow is one as well. There is no such thing as a lossless transduction process: A waste energy is given off, usually in heat. So whether your exhaust spins the vane, or a belt spins the vane - There are more losses at action there than you might think. And those losses are about the same.

    750 watts = 1 hp. Keep that figure in mind. That means that when your stereo is pushing out 750 watts of power, it's costing something somewhere 1 hp. It's coming out of your battery, it's coming out of your alternator. And both of those don't their power from nowhere - they get their power, ultimately, from the fuel getting burned in the piston chambers. Lets say that the turbo electrical fan is 12 volts, and 20 amps (Not many car electrical systems can handle more). 12x 20 is 240 watts at peak efficiency. Lets say there is a transformer in there that steps it down to 6 volts at 40 amps, and then introduces 3 phases. Now it's graphing out on the oscilloscope at 720 watts, pretty smoothly. But that, as you can see, is slightly less than 1hp. Which means that the turbo fan CAN NOT even hope to keep up with a Turbo or Supercharger. Observe transductional losses:
    *Turbo - Fuel is ignited, and starts pushing a piston down. Chemical to Physical. The hot gasses from the detonated fuel and air exits to the Vane of the turbo and cools off (Losing energy) and then dumps out the pipe.
    Supercharger: Fuel ignites, pushes the piston down. Chemical to Physical. That linear piston moves a rotational device 180 degrees (Linear to rotational physical) then that rotational force is geared down to turn a pulley, then through a belt to another pulley, and then to the vanes then it's "physical to chemical" as it introduces more oxygen to the mix.

    Electrical: Linear to Rotational. Rotational to Rotational with electric fields (Rotational to Magnetic) then Magnetic to Electric, then electric to Magnetic, then magnetic to rotational, then rotational to chemical (Introduction of more air).

    The losses are extreme.

    But as I submit to YOU , Hondaswap ! Loud exhaust ALSO has it's own losses ! That noise is produced. The louder it is, the more power to produce the tone - And where is that power coming from ? You got it ! The place that ALL OTHER POWER IN A CAR comes from - The fuel in the piston chamber at the time of detonation !

    Which means that loud exhaust, through a strange twisted path, winds up removing power ! Oh my god !! What will I do ?! If it takes a speaker and an amplifier, 750 watts to produce the same volume and tone of your exhaust, than that sound also takes 750 watts from the engine to be produced. Nothing is free. Your windshield wipers - even at rest (Unless they are hidden) are costing a fuel consumption. Wings that "provide" downforce, Cost on the fuel and combustion. Anything that produces anything on a car ultimately ties into one one thing: The combustion of fuel.

    So in defense of the Electric supercharger: It's all in the way that you use it. With an electric charger you can build up manifold pressures BEFORE you give it gas, thus shaving off maybe a few hundredths from a 1/4 mile. And in competition, that's a valid expense. In daily driving, not so much. But now you know why. None of these devices get energy "For free" because according to the Law of Conservation - There is no "free" energy.

    The only inventions by man that are more than 100% efficient are Bicycles and Wings. And if something isn't shaped like a perfect tear drop, than it's aerodynamically flawed and will have to contend with drag.

    Basic physics. Superchargers, Turbochargers and Electric chargers - nothing is free power. And the proven devices (SC and Turbos) are just as efficient as the other. It's all in where you leech power, and where you want to blow off the wasted energy.
     
  9. Citizen_Insane

    Citizen_Insane Senior Member

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    Actually, Cel, Turbo's are "free power" because they use energy (the interal kenetic energy) of the hot exhaust gases to produce power. This is energy that would normally be wasted by just leave the tailpipe. Sure there is a tiny bit of power lost due to the increased backpreasure from the turbo manifold (or from the intake restriction of the compressor) but it is nowhere near the parasitic loss from a supercharger.

    A supercharger gets its energy directly from the mechanics of the engine and therefore takes power directly away from the drivetrain. Now a turbocharger gets the vast majority (remember I said that turbo's run off of the stored KE in the exhaust gases) of its power from energy that would normally be vented to the atmosphere. Therefor how can a turbo rob the engine of the same amount of torque as a supercharger?

    I'm not going to get into the hardcore thermodynamics of it, I have enough homework that I don't need to be creating more...but I'm just saying that by nature turobchargers are more efficient than superchargers.
     
  10. Celerity

    Celerity Well-Known Member

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    The operation of a turbo charge is more efficient than a supercharger from the source (fuel burn) to the apparatus. Superchargers are more efficient from the Apparatus to the Load (The intake manifold)

    They place the efficiency at different ends of the device itself.
     
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