ADM Electric Turbo / Supercharger

[Tanzy]

I don't think it makes much of a diff in big CC cars. I've felt the thing in action before and it moves a lot of air but whether it can be used to pressurised air is questionable.

 

[Arsony]

E-like-shit supercharger rather....

yky, Tanzy,

This is the umpteenth times someone has come in here asking about this kinda of mod and I think the rest of the guys would probably be thinking...
"ok... here goes Ash again".....

Dont waste your time, money and effort cos here's why...

http://grannypotts.freeservers.com/monkey.html

and

http://www.homemadeturbo.com/tech_projects/el_blower/

and finally to understand why it doesn't work...

From an autospeed test.

"The amount of air that flows into the cylinder, compared with the cylinder volume, is called the engine's breathing - or volumetric - efficiency. In a 3 litre six cylinder engine, each cylinder has a swept volume of 500cc. If the cylinder breathes in only 400cc on the intake stroke, the engine is said to have an 80 per cent volumetric efficiency (ie 400/500 = 0.8 or 80 per cent). Volumetric efficiency will depend on lots of factors (including how well the ports flow), but let's say that the VE of the example engine is in fact 80 per cent. If this 3 litre engine is revving at 6000 rpm full throttle, this means that it inhales 7200 litres of air per minute (remember, one intake stroke per two rpm), or 120 litres per second. To put it in different units, each minute this engine consumes 254 cubic feet of air. To put that into context, a little 60mm diameter PC cooling fan flows only about 18 cubic feet per minute. So, just to flow the amount of air that this naturally aspirated, 3 litre engine needs, you'd need an array of fourteen 60mm fans working flat-out. And that's without creating any boost at all...."

"But let's say that instead of using a belt-drive from the engine, we power the supercharger by using a 12 volt electric motor powered from the car battery. For an electric motor power of 14,500 watts, we'd need a current flow of about 1000 amps (14,500 watts divided by 13.8 volts = 1050 amps). So, to supply the current to drive an electric supercharger having the same airflow output as the most energy-efficient type currently available, it would take 1000 amps. To generate this much electrical power would require at least 8 heavy-duty alternators bolted to the engine. Furthermore, to handle this current, the wires connecting the battery to the supercharger would have to be enormously thick - perhaps brass or copper bars 10mm square would be needed. "

and taken form automotive forums.com/...

"E chargers... unless you want to spend big big $$$ and drive a diesel rig DONT WORK. Anyone who is posting that a fan can produce boost is flat out lying, a fan can move air but not create boost (i.e. pressure) and the centrifugal e chargers that I have seen are junk. Anyone who is trying to sell you something made of plastic (i.e. leaf blower) and telling you that it will create boost is full of it. If you could get 30hp out of your car with an electric fan don’t you think everyone would be strapping toro leaf blowers to their cars? Save your self the time, money and probably damage to your engine and go buy a real turbo/supercharger or go on the bottle. And before you flame me becuase nitrous will ruin your engine I'd rather risk it with nitrous and get some real power instead of getting broken off pieces of plastic sucked into my manifold. Or setup a ram air system, not the ricer ram air systems that arent really true ram air but TRUE ram air, a TRUE ram air setup will create pressure in your intake manifod if it is setup correctly, granted it will not work until you are at speed but I have seen track cars runnig 1.5 lbs with a ram air setup at speed."

So ... like I said. Go save yourself.... get a proper CAI instead... now THAT would give you gains... PROVEN gains.... i

If you have not gotten yours, look for Piggyboyz .... who actually set up a lot of our cars' . You can look mine up at the meetup if you want...

Cheers....

Arsony
Topaz Blue NOT forced induced...

 

[yky]

Thanks for the advice. Much appreciated. To think of them having the temerity of selling the charger at that price....

 

[Shaun]

Arsony, computer fans are very different in specification compared to the bilge blowers that these kits run. Bilge blowers support around 300-500 CFM, but at very low pressure ratios (1 psi or less). Still a PSI is a PSI and it does help.

It works in theory, and I've seen it work in real life dynoed, gain was small. I talked about this on Delphi before. It was a 2.5L engine, power across the range all the way till redline. IIRC somewhere around 7hp.

I hate little do-dads that do nothing, but this does do something - just that it costs a lot. You could get your own bilge blower for 1/3, 1/4 of the price and run it pre-filter and there would be no problems. I would never pay 600-900 bucks for a bilge blower.

 

[Racebred]

i wonder if these things actually restrict air flow at higher car speeds.

 

[Whisky_Tango]

Generally, 1 PSI of air will give you 1 PSI of fuel.
So more air and petrol give you more power.

I suppose, this device helps in low end to mid range. On the high end, the flow somehow balance out with the WOT flowrate.

If Im not wrong, WOT for 320i is 580kg/s thereabout. This is measured in Mass.

Taking 500CFM which is measured in volume. Covert to L/s (1CFM=0.472L/s)

= 500 x 0.472
= 236 L/s

Taking density of air = 1kg/m3, convert to kg/s (1m3=1000L)

= 236L/s x 1Kg/m3
= 236Kg/s (where the L and the m3 are crossed out)

So Shawn's concern is valid, as the fan max out at 236kg/s which is smaller than required by the engine of 580kg/s less my assumption of 580kg/s is wrong.

 

[Shaun]

only if engine consumes more than the blower is speced to flow. and that will only happen on the larger displacement engines. few cars have true ram air setups. and if there is ram, the ram is not lost but helps the blower compressor efficiency. This is assuming WOT with the blower blowing.

PART THROTTLE - high speed throttle openings just below WOT will yield the largest restriction but this is not a big deal because these throttle openings are very rarely used in driving unless cruising at high speeds. Even then a loss can be compensated for by opening on the throttle further. In any engine the limit is WOT and the fact the blower extends this limit is a pure positive. You are only changing where the restriction is.. there is no true restriction because as you offset it with throttle opening and eventually set it off and the ceiling is raised. The only thing is that between 99% throttle and 100% there is a non-linear increase in power but because the difference is so low to begin with (1psi or less and sub 10hp), it doesn't make a diff

 

[Racebred]

ordinary people write one sentence. (like me)

engineers say the same thing but one whole page of equation all come out. hehehhe

 

[Shaun]

Generally, 1 PSI of air will give you 1 PSI of fuel.
So more air and petrol give you more power.

I suppose, this device helps in low end to mid range. On the high end, the flow somehow balance out with the WOT flowrate.

If Im not wrong, WOT for 320i is 580kg/s thereabout. This is measured in Mass.

Taking 500CFM which is measured in volume. Covert to L/s (1CFM=0.472L/s)

= 500 x 0.472
= 236 L/s

Taking density of air = 1kg/m3, convert to kg/s (1m3=1000L)

= 236L/s x 1Kg/m3
= 236Kg/s (where the L and the m3 are crossed out)

So Shawn's concern is valid, as the fan max out at 236kg/s which is smaller than required by the engine of 580kg/s less my assumption of 580kg/s is wrong.

Eric, your figures are off.. it is not kg/s . it is g/s . if you could move 580kg/s you would be outrunning every car on the face of the world hehehah

I also do know that a 320 will not max out at 580g/s. 240hp cars max out around 250g/s. You can confirm this with logs. I can guarantee you that a lightly-modified 320 will not flow more than 350CFM at a 6500 redline.

 

[Whisky_Tango]

only if engine consumes more than the blower is speced to flow. and that will only happen on the larger displacement engines. few cars have true ram air setups. and if there is ram, the ram is not lost but helps the blower compressor efficiency. This is assuming WOT with the blower blowing.

Your statement is also logical as in during WOT, engine is still drawing 580kg/s for example and this fan is blowing at max 236kg/s but did not totally block the intake pipe instead its existing the air flow.

hmm... pondering now...

 

[Shaun]

bro, it definitely is not kg/s ! I promise you this it is measured in g/s . I've run multiple motronic MAF logs. I am not about to do the math for all this but think about it... BSACs are all measured around 6 lb/hp-hr and . How can you be flowing 500++ kg per SECOND on a 2.2 litre car?

 

[Whisky_Tango]

Generally, 1 PSI of air will give you 1 PSI of fuel.
So more air and petrol give you more power.

I suppose, this device helps in low end to mid range. On the high end, the flow somehow balance out with the WOT flowrate.

If Im not wrong, WOT for 320i is 580kg/s thereabout. This is measured in Mass.

Taking 500CFM which is measured in volume. Covert to L/s (1CFM=0.472L/s)

= 500 x 0.472
= 236 L/s

Taking density of air = 1kg/m3, convert to kg/s (1m3=1000L)

= 236L/s x 1Kg/m3
= 236Kg/s (where the L and the m3 are crossed out)

So Shawn's concern is valid, as the fan max out at 236kg/s which is smaller than required by the engine of 580kg/s less my assumption of 580kg/s is wrong.

Eric, your figures are off.. it is not kg/s . it is g/s . if you could move 580kg/s you would be outrunning every car on the face of the world hehehah

I also do know that a 320 will not max out at 580g/s. 240hp cars max out around 250g/s. You can confirm this with logs. I can guarantee you that a lightly-modified 320 will not flow more than 350CFM at a 6500 redline.

Thanks for the highlighting the fact.

So eventually based on calculation, this fan does produce higher flow than required.

 

[Tanzy]

I'm more concerned with the fan running the battery flat on the long run. I heard it consumes as much power as the electric starter motor.

This E. Aircharger is also variable and I think it's tapped on to the MAF or vacuum sensor.

 

[Shaun]

10% high corrected

math

500 CFM = 14.16 m^3 / min = approx 14kg/min = approx 210g/s

3.0L at 6500 redline and 100% VE (generously) = 350CFM = approx 160g/s


both assuming air is around 90 F

 

[Shaun]

to clarify the previous 240whp quote was off. it is more like so about 290 whp. Don't let that quote throw you off.

so it appears a 500 CFM bilge blower will become a restriction at around 374hp. Even substantially modded 3.0 NAs don't need to worry. But first you need to find out the true rating of the blower model used. THey range from 300-500CFM

 

[Racebred]

for comparison, what is the cfm of a belt driven supercharger?

 

[Shaun]

I have never seen a supercharger compressor map before.

but you can look at turbo compressor maps. a turbo like a TD06H-20G can provide 500CFM at a pressure ratio of 2.4 (20+psi) and around 75% adiabatic efficiency. FAR superior to a bilge blower as you can see.

 

[Shaun]

looked around out of curiousity after your question and found a Vortech V1S-Trim supercharger flow map. it is capable of 750CFM at 9psi at 72% adiabatic efficiency. Shaft speeds of around 35,000 RPM vs turbos typically running between 70,000-150,000 RPM.

V1S must be some sort of monster trim for V8s. if you had the crank and SC pulley sizes on a specific engine, you could calculate very precisely where you'd be since shaft speed is fixed in ratio to crank speed. not so simple for turbos

 

[Racebred]

the ASA SCs are much faster, running up to 15 times your rpm, which for a BMW, is close to 100000rpm. read it in BMW CAR.

 

[Shaun]

15 x 35,000 RPM = 525,000 RPM

?? half a million RPM ? are you sure?