tank12983

I have seen those electric super/turbo chargers for sale on eBay and other places but as we all know they are junk. But on youtube yesterday I saw a video of a brush less electric motor hooked up to a electric blower that had enough power to blow a full beer can across a table. now I had been kicking around the idea of a good electric turbo for a while because I didn't want to do anything irreversible to my car which would be required to do an actual turbo.

The very concept of a electric turbo has some very fundamental problem like powering, the parasitic drag when the turbo isn’t in use, which type of turbo should be used, and how the boost should be delivered. I have come up with a few ideas, questions, and problems.

if you took one of the battery relocation kits and used it to have two batteries you could use one for normal operation of the car and the other to power the electric supercharger. now this brings up a problem. you would have to recharge the secondary battery all the time but I came up with a solution with this. I have the pace setter headers so my smog pump isn't doing anything so you take off the smog pump and put on another alternator to charge the secondary battery. now I don't even know if that would work and I'm probably just saying mumbo jumbo, but its makes for a interesting idea doesn’t it.


I have seen two main types of electric superchargers a squirrel cage one and a inline turbine one. But I would think the inline ones would have less parasitic drag. if you were to use the squirrel cage I would think that you would have a type of dual snorkel intake to counteract the drag. with one end hooked up to a normal air filter and the other end hooked up to the squirrel with a inline air filter and some sort of valve that would shut the normal air filter as to not let the air that super charger generates out the normal air filter.

what I personally think would work best is sticking with the dual idea but instead of have one I would have two of the turbine inline superchargers with inline air filters. one on each snorkel. my reasoning behind this is that
1 it would save space using inline superchargers not that there is that much of a lacking of space considering the room where those 2 cylinders should be but still.
2 with two superchargers you would not need a valve that wouldn't let the boosted air out when you are using them. the two superchargers would push against each and have no where else to go but into the engine
3 with two superchargers the drag created when they are not in use would be cancelled out because of the dual snorkel letting enough air in

the only thing that would be different between two inline and two squirrel cages would be the amount of space you can come up with.

here is another problem would you use the electric supercharger like normal forced induction or like nitrous. To put it another way would you rig something to the throttle so that it would respond like a real supercharger or would you just have a switch that would turn it on and off like nitrous.

P.S. I have posted this in the v6 section aswell because i didn't really think that any v8 guys would be too interested in this, but you never know

83TransAmRECARO

I was involved in a project similar to this in high school only we bolted it up to a crustang... we wired up a microswitch to the side of the throttle stop and added a battery to the car wired in parallel. the batteries were mounted in the trunk however... we ran a few test on the car and only changed the 1/4 mile time by tenths of a sec... however the joke remained of a hair dryer on a 4 cylinder car... but if you have found a air supply that has alot of force it may work... we were using a bird cage design built by the hvac class...
I'm not sure about the extra alternator... seems like it would rob you of more horsepower than it would benefit... just my constructive thinking...
I hope you get it to work out for you... good luck on it either way...

Street Lethal

iTrader: (16)

That's exactly what those concoctions lack....

okfoz

I once thought about mounting a starter motor to a blower or a turbo...

Only at WOT it would hit a switch that would turn on the motor. To overcome the parasitic drag for when not in use I thought about a door with a really weak spring that would open due to the added air pressure, when you were no longer in WOT the door would close, the door may actually work with or without a spring as in theory it should open based on what had more air coming through at the time...

A starter motor has a lot of torque so you might actually be able to gear it for better performance.

I know you do not want it running all the time, due to starters tend to die if they are run for too long and get hot... I figured for a 15 second Quarter mile it should be fine...



John

junkcltr

iTrader: (1)

Before you guys go all crazy with "new" ideas...............you might want to do the calculation to see how much HP is required to push air into a 305ci or 350ci engine. The electric motor is going to be giant and much larger than a SC or TC.

A simple search before posting would have shown that this idea has been around since the early 1900s.

EDIT: a starter motor would make about 0 - 1 PSI of boost at full load (300 amps)

okfoz

I want to think I did the math and came up with the same conclusion...

Interesting idea anyways...

John

junkcltr

iTrader: (1)

I think a better setup is an electric start CR500 (2-stroke) engine running a SC in the trunk. You fire it up when you need the extra HP. It would put a car in the 9s and the power to weight ratio is better than the SC on the car engine. Less than 1 MPG lost due to the added weight.

tank12983

aren't we just a little pessimistic. I have a 3.1L v6 with a stock cfm rating of 308 not that much

here are some videos that are not the one i mentioned in the post but are still impressive. a friend of mind showed me the other one and i don't know the address

http://www.youtube.com/watch?v=lgWJYgcWB4w
http://www.youtube.com/watch?v=iFWJ_amrCh4
http://www.youtube.com/watch?v=VdLgF...eature=related

its simple it comes down to this:
is it going to be as good as a real turbo NO
is its going to be as expensive as a real turbo NO
do you have to pay for refills of your nos tank NO

and at any rate I doubt that I'm going to do this now or even but if enough people kick around enough ideas you never know it might become possible

Street Lethal

iTrader: (16)

^ The problem with those demonstrations, is that there really isn't any pressure being forced back to the electric turbo. Nobody is saying that they can't move air, as even house fans can do that, but testing it's ability in a closed off (not open ended) setup is the real question at hand. To apply a substantial amount of psi after the "zero" inch vacuum point has been realized is a totally different task from just pushing and crushing empty soda cans....

junkcltr

iTrader: (1)

Nah, just being real. One always needs to do a feasability study before building anything. You will hear people talk about compressor maps, pipe size, etc all before building a turbo or supercharger setup...........to pick the right parts and to see if it is worth building.

So here is some info for you to see if your setup is worth building.
1) Using a stock 3.1 liter engine as you stated, it takes about 4.5 HP to make 2 PSI of boost at 5000 RPM
2) 4.5 HP is 3.4KWatts, that means you need 3400/14 = 242 AMPs. That means you need an battery that can provide A LOT of amps between boost usage. You need a dump truck alternator pretty much or you will destroy batteries. A car battery is destroyed with deep discharges.
3) You gain ((2+14.7)/14.7)*140 = 19HP at 2 PSI of boost

Overall, you need a supercharger, a 3.5KW motor, a giant alternator.....................all for a whopping 20HP gain. As you can see this is why no one does this setup. If you feel the 20HP is worth it then by all means build it.

This is fact........you may perceive it as being pessimistic. You could also perceive it as optimistic in that 20HP is better than nothing.

You can't beat a turbocharger for efficiency.


Consider it kicked.

tank12983

lets consider this
http://www.rctoys.com/rc-toys-and-pa...RS-HACKER.html

2600 watts at a weight of 795 gram (that's a little less that 2 pounds) 5200w with a twin setup then use the battery they suggest forgetting the extra battery+alternator idea (10 cell 37V 8000mAh LiPoly batteries) since its a R/C battery i think it will handle depletion and charging well, rig it in the nitrous fashion. OK so its not going to give you top end power, what will it give you off the line

tank12983

if i calculated that right that about 7 horse power and 3 psi, my engine has 83k on it and 3 psi sounds good enough to me.

Street Lethal

iTrader: (16)

^ Why not just re-design the entire engine, for that matter (and I'm being very serious). Tyco electric slot cars FTW....

junkcltr

iTrader: (1)

10*37v*8A = 10*296 = 2.96 KWatts
2960/746 = 3.96 HP

So, using all those batteries will get you almost 2 PSI of boost. What is the AMP/HR on those batteries? It will tell you how long you can boost between recharges. Oh yeah, where are you going to find a 37V DC motor that is rated at 5HP continuous?
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That is wrong. Show the equations that led you to 7 HP and 3 PSI. What you posted is about 4 HP and less than 2 PSI of boost (about 15 BHP - at the crank).

Sure, it sounds good but figure in the cost & fab. time and it is a waste. Just put a N2O 20HP shot on it and the bottle will pretty much last "forever"..........compared to pulling out batteries and recharging them.

EDIT: All this is assuming no wiring or motor loss of energy. Taking into account these losses will put you in the 3 - 3.5 HP range which will make about 1 to 1.5 PSI of boost or about 10 - 15 HP at the crank.

tank12983

pretty sure the watt rating of the motor is it power it produces when its turning and you equated out the power of the batteries with is just one 10 cell battery not ten batteries... but any way two motors have 5200 watts of turning power assuming kilo still means thousand that's 5.2 kilowatts which converts to 6.97 horse power (7) then I looked at your equation seeing that

3.4kw=4.5hp=2psi and assumed that it take
2.25hp=1psi so i said that said that
5.2kw=7hp=3psi at 5000 rpm. and since we're discussing like friends and not debating like enemies I would still like to know what it would give you off the line

here is a chart that shows the depletion rate of the batteries and the site says the it take 4 hours to recharge the batteries and a half hour rest period after the charge

http://www.batteryspace.com/ProductI...e/8Ah_pack.jpg

junkcltr

iTrader: (1)

The motor you have sounds like a 5200 Watt motor. Are you sure it can handle 37 volts?

You still only have 2960 of power (fuel) to feed that 5200 watt motor. Think of it like having a vehicle 500 HP engine but only enough carb(fuel) to make 200HP.
So, because of you only having 2960 watts of fuel then you only get 2960 out of that motor which translates to less than 2 PSI of boost.

What do you get off the line....???
Assuming a 3.1 engine with a 4 HP battery supply to feed the 5 HP motor:
This will give 2.5 PSI at 3600 RPM and you would get about 30 ft/lb at peak torque at the crank. It would be a little quicker off the line and you would feel it.

Using that chart shows that if you used 10 of those batteries you could run full boost for 1 hour continuously.

You might want to look into tncscooters.com for parts. They sell the motor, batteries, and speed controllers. I have an electric scooter I picked up used to experiment with boosting some briggs & stratton engines (yeah, I play around with stuff besides just doing science/math) . I might go electric or smog pump. The electric would work nice for a wood splitter or weldernator.

tank12983

what i was trying to say or find out is would two squirrel cage fans both with one 2.6kw motor powered at the correct optimal peak both blowing into the intake create

also here is another interesting blower http://www.electricmotors.com/index.html

junkcltr

iTrader: (1)

Squirrel cage fans? Post a pic.
A lot of engineering goes/went into SC and TC compressor fans. I would be amazed if you can make any other fan work to build boost using the electric motor setup.

Those motors are just your every day industrial motors that I originally said you won't fit under the hood with the SC or TC fan setup. They would allow you to make a normal PSI range and require the truck alternator and deep cycle back woods batteries.

tank12983

these motors aren't that big the weight about 800g as i mentionsed be for but i don't know the dimension. the reason I used them for my concept was because they are brushless electric motor which are stronger faster lighter smaller than normal electric motors

junkcltr

iTrader: (1)

Just make sure you aren't looking at the AC high HP motor. Those are typically brushless squirrel cage design. You typically see them on air compressor of 3HP and up and in industrial machines. I think you are confusing DC and AC motor design.
My 5HP 240v air compressor motor weighs about 90 lbs. That 90 lb unit replaced a 110lb unit. Your best bet is a 36 volt scooter motor.

tank12983

the motors are for R/C helicopters and air planes and that they can power models that weight 30lb, that's a really big R/C model what you consider a 1.75lb motor is powering it. they are definitely DC motors and i was thinking of using something in the ballpark of this for the actual turbo in loo of using a real turbo but with only the fan hooked up to the motor

http://www.sears.com/shc/s/p_10153_12605_07179242000P
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I know its HIGHLY impractical but imagine piping this into the intake
http://www.sears.com/shc/s/p_10153_12605_00990909000P
2900 to 4000 cfm that incredible

scribbles

I got a cheap *** SC, i will only have a grand into it when done, and should make a solid 6-7psi on a 350, It would take a 40hp electric fan to do that, electric dosent work.

tank12983

1 I don't have a 350 so there is no cheap easy bolt superchargers to Put on my 3.1L v6
2 I don"t want 6 to 7 psi i have plus 80k on the engine
3 I don't want to spend $1000

scribbles

I was trying to comment on the fact that you need to move a lot of air, and keep the heat to a minimum, you will spend Way more than 1k on an electric setup that will give you 1psi at say 6000rpm. With a v6, just fab up a junk yard remote turbo, you should be able to get 3-4 lbs out of that. You could set up a Meth injection setup for say 150-200, should give you another 14-18 hp at WOT, and be better for your motor that shattered plastic bits getting eaten by your intake. Or just get nitrous, drop on a 75 shot, be 55hp ahead for not much more money