Sometimes if you wish for something long enough ... you actually might get it. Case in point - the much maligned phantom "electric supercharger" - now in a slightly upscale version from the traditional ebay offering and called the 'VTES or Variable Torque Enhancement System".

Some specs:

- 0-70,000 rpm in <350ms
- shaft power 1.8kW
- Max pressure ratio 1.45
- max current 350A
- compact size
- easy placement

http://www.cpowert.com/products/vtes.htm

and look at the 'download procdeuct data sheet' pdf for easy reference. I didn't see a compressor map, but they must have that info.

I'm far from an FI expert, but this would seem to offer some promise for the rotary. Can some of the fi gurus chime in and tell us whether this is something feasable for at least intermittent use? Wouldn't it greatly simlpify fi in the rotary being so compact? It would seem to possibly be an easy (ier) DIY kit compared to the traditional turbo or supercharger?

And btw something like this unit is rumored to being considered for the next 2014 BMW M3 (reference story C&D), and the company and the product appear legit

Does the offer of development assistance get anyone excited? Opinions please.

 

Well the amp draw and other specs seem reasonable for something that works. Might be an actual product. Development assistance is kinda scary. 350amps at 14 volts is 4900 watts. That's enough to destroy both your alternator and battery pretty quick.

 

BMW is experimenting with a small electric super charger.

 

Looks cool.

From what I could read, I think our engine is too big. We have a 1.3L 2 cycle engine that turns at 9,000 RPM. If the biggest engine they listed was a 2L, might be trouble..

However, the supercharger guys have also shown that a little boost goes a really long way in a rotary engine, and this is not blocking the exhaust like a turbo does...

I seem to think the BMW application was for the short term to combat turbo lag, but am not sure.

Cool find.

 

looks like they're using their own battery for power delivery. I didn't see it in any of their pictures but sustaining 5000 watts is some serious ****.

 

Exhaust gasses are still mostly free to use...
A 5kw electric system isn't.

 

350A was the acceleration use draw, 220A the steady state draw ... so only (!) 3080 watts. A small Lithium pack can do that easily for short periods with charging (perhaps alternator + brake regenerative?) in between. BMW is saying they plan to use exhaust heat generated electicity by thermoelectric semiconductor material.

With electrical power taking over many car functions like steering assist, water pumps, air conditioning, etc., out-of-box thinking is removing mechanical components from the car and the direct mechanical load removed from the engine. The major benefit I see from this is the conversion of mechanical functions to electronic is that it allows far far greater precision, control ability, and efficiencies, plus space and weight savings over the mechanical parts.

Think of some historical mechanical to electronic progressions. For example, once the village clock tower was the only way to know time, no watches were available. Then the clock tower got distilled to a mechanical watch that fits on you wrist, but they were expensive. But once the electronic conversion and miniturization of timepieces and timing based equipment came about and progressed - it cheap and far far better than before and in virtually every device available today.

It's happened to so many complicated mechanical products before, and the car electronics revolution is just beginning.

 

Perhaps LiFe... not sure I'd be comfortable with LiPo or LiIon with sense of safety in a "small" package. At least not for the average Joe without a serious over/under charge/discharge protection circuit.

My guess is to survive a 350A @ 12V peak you'd need 12+ cells in a 3s4p setup. That's a brick about the same size as a conventional car battery, would be good for a hundred or so discharge cycles and run between $200-$400

 

yall are not thinking things through. Remember a supercharger also helps an engine even when it is not in "boost".

 

^ slkrug .... ummm ... you are flat out wrong and missing the whole point. The answer is that the extra power produced comes from burning extra gasoline, not from transfering electrical energy from the battery to the supercharger to the engine. The supercharger is the enabler, not the producer of power. Sure it uses some energy itself, but way less than the extra produced by pressurizing/burning the mixture.

 

i remember the same type arguement being used concerning how the electric water pump couldnt work. It would require too much energy and any hp gain would be negated.
that was proved wrong and this will be too.
Maybe if they removed the word supercharger and call it an electric booster pump or something then it would be thought of differently.

 

If you were right then superchargers as a whole would be bullshit products. In your mind any energy that would have gone to working the supercharger from the engine would be lost since it couldn't put the same amount of energy back. In this instance the example isn't any different from the typical mechanical supercharger.

 

What will be tricky is the intake air path when the 'charger is off. If the off mode simply routes air through the unit, it will create considerable resistance. Probably a VFAD-like shutter is required. One likely wouldn't want the charger on during light throttle where the throttle plate is mostly closed and na is sufficient to supply the requested power. It should come on only when power requirements are high and the throttle plate is mostly open, kinda like water/meth injection. One could combine the two perhaps and reduced the need for an intercooler.

 

As far as when to use this....quite the contrary to what you are saying. If you read thru the material on the site, it pretty much limits use to low RPM but instant TORQUE applications. This was what an electric supercharger in the RX-8 was once supposed to do once upon a time. Where the rotary is weak is low end torque, that's why it's geared down so much in 1st/2nd and feels so lethargic starting off ... no torque.

Imagine instant (ok - 350ms) 200ft-lbs of torque with a touch of the gas at virtually zero RPM. The site speaks of assist until a real turbo takes over for larger engines, and all the graphs shown regardless of engine type/size are for extra boost at under 2000 to 3000 rpm.

I do see that a VFAD like thing would be helpful for taking it out of the air path at higher RPM though. It doesn't seem that there's enough flow to accomodate higher RPM use in an engine our size... maybe they come in different sizes ... dunno.

 

^ Not at all. HP = (torque x rpm) /5252. I didn't mention rpm at all. If you're at 4k rpm, fully open the throttle, it blows. If you're at 8k, throttle closed, it doesn't. Efficient and appropriate use would be much more related to manifold pressure than rpm. If the unit can't supply the volume of flow needed for full engine output, then of course, it'd have to be switched off and air shunted around the compressor. Their site does put a lot of emphasis on diesels which would be simpler to deal with, having no throttle plate to complicate things.

 

Aren't the seals particularly vulnerable under high load, low rpm? Is that a time you want to be applying any kind of boost?

 

What HP gain? When certain device pumps liquid and is driven by simple mechanical means, its more efficient than losing energy in alternator, wiring and electric motor itself. EWP does have benefits, but you completly missed them...

You completly omitted what Renesis flows. I went through their documentation and these is no airflow number. They just tell that this device on very small displacement 4-stroke piston engine can increase power by 25 kw. From this I can assume that this device can supply about 4 pounds of air per minute at 1.45 PR.

Renesis will outflow it by 1500 rpms with atmospheric filling...
And for real, who drives rotary engine at such low speeds?
Example with 2.0 boosted engine is understandable, this device will increase mass flow which in turn spins the turbine earlier, but again, not applicable in this case.

Really, they should generate compressor map for such product. With some guesstimation work, you could calculate what kind of airflow at what PR it could support with power it draws or from their "shaft power".

Much more interesting device is their TIGERS system, which should extract energy from exhaust gasses via turbine, but again, they don't quote any corrected mass flow and PR requirements to supply rated power...

Seems dodgy to me, or they are just plain dumb and doesn't know how to evaluate these devices correctly...

 

^ lol I didn't 'omit' anything. I don't even know the answers, no less the questions that need answering! That's why I posted this here in this section!!

But if what you say is correct, that's good info ...maybe not a good mix with the rotary. Thanks for that!

I don't think this is a 'dodgy' product, whatever that means to you, rather it's simply a new solution to problems people are just beginning to consider and work at. It may work for some, not others, time will tell, but I'm SURE they never had the rotary's unique problems in mind when developing it.

 

I choose not to get into all the benefits of the ewp in this thread. Anytime parasidic draw on the engine is reduced then that is directly reflected to an increase of power to the drive wheels. Poeple used to make the arguement that the increased draw on the alternator would negate the parasidic draw reduction that the ewp provided. That has proven to be a false.
I have been running a supercharger for a few years now. The off boost throttle response and power is still greater than oem . You have to ask yourself why is that?
I think the elctric supercharger could be switched and also have a bypass valve for lifted throttle needs etc. It will be more of a use that a lot believe.
For giggles--get an electric leaf blower and hook it up to your intake (post maf please) and see if it makes a difference --lol. Now dont go and blow the engine

 

So.. use TWO of them.

 

Homogenizer.....

 

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