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Originally posted by Josch:
Yeah ok, let just go salvage a Caterpillar starter off a D-12 Earthmover, and then you can put 2 big batteries in your trunk to spin it up and create your boost, and the instant you floor it (and your WOT switch engages the motor's solenoid) and your batteries rapidly drop in voltage as your motor spins up to speed, then your alternator (if sized correctly) will put your same 10hp load on your crankshaft thru the alternator belt as it tries to keep the batteries charged.
The whole point of using electricity instead of a belt is that you avoid putting that load on the engine... I've never heard of any car having a ten horsepower alternator. Ours is two horsepower.
Originally posted by Josch:
If your alternator is too small (like stock amperage), it will just full-field your alternator for a long time to try and charge your batteries and will overheat and likely fry the diodes in it....
It's simple enough to protect against that, if it's a real risk.
Originally posted by Josch:
Ok, (you think) why not just rig up a simple WOT switch to shut off the field current to the alternator (shutting it down) for while you get on it?.... so then after you put that on, you floor it and watch your voltmeter drop down to 10 volts as the boost kicks in and your ignition system gets very weak and combustion becomes less complete (especially at the higher rpms when you need the hottest spark under those boost conditions). You don't believe me? Try it and see....on a backyard budget even?
A simple matter of sizing your batteries to the job. A single Optima red-top can put out something like 15 horsepower, and if I use two, I doubt you'll see enough voltage drop to worry about. Or, I could isolate one battery at activation time, keeping the rest of the car at 14V. I'm also considering possible 24V arrangements (though this might require finding a way to reconfigure the coils inside the motor), which would reduce the need for a ten pound thyristor. There are all kinds of options.
These are all issues that are quite manageable with a little care and foresight. I don't know why you make such a big deal out of them. You already posted some really unrealistically pessimistic stuff before, and I don't see you revisiting those ideas once the mistakes were pointed out...
Originally posted by Josch:
Even more impossible. Automakers couldn't even do it.
What do you mean, couldn't? When did they try? It's not that they couldn't, it's just that they didn't. For probably very reasonable economic reasons.
Originally posted by Josch:
Big diesel engine companies really could profit from this method if workable.
Your thought processes are pretty confusing here. Big diesel? This is a technique for small engines. Two liters is about the most I'd want to try this with.
Originally posted by Josch:
They still can't figure it out either. And you hope to acheive this on a shoestring budjet?
Sometimes I wonder why I bother trying so hard to reason with the unreasonable
Which one of the two of us is doing any actual reasoning here? Like, where in any of your, cough, reasoning have you come up with a single number that means anything?
Originally posted by Josch:
But if you DO do it and succeed, then you can market it, sell it to all the automakers and big diesel companies, get rich, and then come back here and laugh at all of us here and you can tell the world how wrong us stupid skeptics were 
No, I'll simply tell owners of small engine cars that they now have another choice. For anyone who thinks bolt-on NA performance is not enough but a multi-kilobuck turbo setup is too much, this is a nice option in the middle, where we currently don't have much of anything.
Perhaps I should also mention that I half intend to get me an actual electric car some time in the next five years, and a project like this is good practice in that direction. It's like a miniature model of an electric drive train.
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You know, this business of defending an experimental idea was exactly what I did not want this conversation to turn into, when I first asked about the value of intercoolers. Originally posted by Rara:
So, for Paul's assumed 35kPa boost pressure we get the following.
Pt = 5.00kW
Now, typical centrifugal compressor efficiency is something like 65% so:
Ps = 5kW/.65 = 7.69 kW at the electric motor shaft. This is roughly 10.3 hp required from the motor.
That's just about the same number I came up with by taking a rough guess at the inefficiencies. In summary, with either your figures or mine, it's at the difficult end, but certainly not impossible.
Originally posted by Rara:
Now, assuming your 12V system, this is roughly 650Amps running ANY TIME you wish to have boost,
Correction, not ANY time you have boost, but any time you have maximum boost at high RPMs. 90% of the time the demand is lower. (One advantage of electric boost is you can regulate the demand to exactly fit the need, instead of taking too much and throwing away the part you don't want, as all mechanical boosters do in some parts of the powerband.) And note also that if the system fails to give you this much power, that only affects the high end; you might have 6 psi at 4000 rpm and 4 psi at 6000. Since the car's present behavior is that you really feel an increase in pull as you go above 4000, that could still help quite a bit.
Originally posted by Rara:
Now, Paul was looking for ~200hp w/ his 5psi, and that ain't gonna happen,
Of course it's not. I never said I expected 200 hp, I only said I had no interest in anything beyond that.
So never mind the second, higher boost scenario.
Originally posted by Rara:
Oh, I also failed to mention, that your typical centrifugal compressor will be spinning well over 100k rpm to meet these flow requirements, and whatever magical wonder motor paul chooses to run will need to be even bigger to account for the additional losses due to the required gearing to run the compressor at the appropriate speed.
I was figuring on using a belt. Is that bad? And I thought it was only like 30k rpm... If it's 100k, that means gears, which would be more difficult and annoying.
Originally posted by Rara:
You have been whining about the cost of an intercooler becuase you want to do your project cheaply, but really, do you think even a version of this that doesn't even work well is going to be cheap? An intercooler, even a new one from spearco, will be a drop in the bucket compared to the cost of the required componentry for this sort of a setup.
I thought we settled the intercooler issue a month ago. I already told you I'd use a basic air-air cooler. If you're going to talk down to people, it helps to listen first.
Originally posted by Rara:
High current motors, custom compressors and gearing, much larger alternator, 2nd battery, high current electrical distribution and control components, most all needing to be custom made.
Depending on how much I use it, there may not be that much need for a larger alternator. Other users might want one.
As for the custom making, that's just hobby value. There's not much I'd have to farm out to anyone.
Originally posted by Rara:
All for the same amount of hp that could be had in the other motor offered in the car stock, and all the time, not just for extremely short bursts of time. And to top it all off, you still wouldn't be legal to drive the car in california. Though, you could anyway, and really piss off all your neighbors over in Berkeley.
I guess your suggestion is to buy a different car.
Hell, my CTA intake isn't legal in California, and this system could pass the same way the CTA did last time: unlike a turbocharger, it can be easily dismounted.
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Thanks everyone! I now know less about tcs and scs than before by reading this section of the forum. I now plan to reread the entire thing minus Paul's random babblings. Paul, it does not take 9 pages of posts to prove you're right if you are, in fact, right. Quoting everyone's counters and picking apart their advice is not agreeing with 90% of what they're saying. It's trying to prove you're right. These guys know more about forced induction than you do. IT'S A FACT. Instead of trying to prove them wrong, LISTEN TO THEM!!  In the short term, yes, it isn't cost effective to use an intercooler. However, 3 months down the road when you've replaced your head gasket 4 times, it will seem really cost-effective. There are some good ideas when it comes to using electric motors, but not for turbos. It is best to go mechanically driven for turbos, since so much power is required to drive the electric motor. If you're really itching to stick an electric motor in your car, go with the electrically-driven water pump from batinc. And please, please don't quote this post. Last thing I need to see is a little box inside one of your posts with my words in it 
I ran a search already!
99 Ford Contour SVT - SOLD!! 
'90 CRX Si, '98 Explorer V8, '98 Acura ITRally Co-Driver
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Originally posted by imnotted:
Thanks everyone! I now know less about tcs and scs than before by reading this section of the forum. I now plan to reread the entire thing minus Paul's random babblings. Paul, it does not take 9 pages of posts to prove you're right if you are, in fact, right. Quoting everyone's counters and picking apart their advice is not agreeing with 90% of what they're saying. It's trying to prove you're right. These guys know more about forced induction than you do. IT'S A FACT. Instead of trying to prove them wrong, LISTEN TO THEM!! In the short term, yes, it isn't cost effective to use an intercooler. However, 3 months down the road when you've replaced your head gasket 4 times, it will seem really cost-effective. There are some good ideas when it comes to using electric motors, but not for turbos. It is best to go mechanically driven for turbos, since so much power is required to drive the electric motor. If you're really itching to stick an electric motor in your car, go with the electrically-driven water pump from batinc. And please, please don't quote this post. Last thing I need to see is a little box inside one of your posts with my words in it
Too late! 
Former owner of '99 CSVT - Silver #222/2760
356/334 wHP/TQ at 10psi on pump gas!
See My Mods
'05 Volvo S40 Turbo 5 AWD with 6spd, Passion Red
'06 Mazda5 Touring, 5spd,MTX, Black
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takes another hit from this post... In the morning my wife likes to cuddle, and this morning, as I was lying in bed, wide awake, I was thinking, what if we could use Paul's idea to supplement a conventional turbocharger? Use it to "preload" the system until full boost is being provided by the regular turbo? Use a stored electrical charge to run the compressor, and when it is no longer needed, it shuts off, and recharges. It could be recharged by alternator, when the car breaks (like hybrids), or someother use of existing kinetic energy, or a combination of all of those. takes another hit from this post... I really need to get some professional help 
Contour--It will make a master mechanic out of you!
95 LX MTX Bolt-ons
95 Neon SOHC ATX
77 Dodge Powerwagon-more displacement than my Neon, Contour, and wife's Saturn---combined!
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"Absolut Rara."
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Originally posted by Oeneus:
takes another hit from this post...
In the morning my wife likes to cuddle, and this morning, as I was lying in bed, wide awake, I was thinking, what if we could use Paul's idea to supplement a conventional turbocharger? Use it to "preload" the system until full boost is being provided by the regular turbo? Use a stored electrical charge to run the compressor, and when it is no longer needed, it shuts off, and recharges. It could be recharged by alternator, when the car breaks (like hybrids), or someother use of existing kinetic energy, or a combination of all of those.
takes another hit from this post...
I really need to get some professional help
better yet, rather than a seperate setup, why not directly couple the electric motor to the turbo charger to simply help it get up to operating speed faster?
In fact, there are companies doing just that right now. Though I can't say that I know of any in production. While in theory it is a great idea, in practical application there are a lot of things that hinder it. To steal a german proverb "The Devil is in the details."
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Perhaps a magnetic field coupling since the turbine is so light? That way it wouldn't actually be in contact with the turbine.
war...
Former owner of '99 CSVT - Silver #222/2760
356/334 wHP/TQ at 10psi on pump gas!
See My Mods
'05 Volvo S40 Turbo 5 AWD with 6spd, Passion Red
'06 Mazda5 Touring, 5spd,MTX, Black
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Water injection will cool the intake air, but water is non-condensable so it will increase compression ratio.If you want to see the difference between your engine running with cool air and hot (ie boosted) loose a water pump and wait to see how your engine runs at the higher compreesion created by the high temp.I lost the water pump in my 84 Mustang GT and the comprssion got so high that it would'nt even crank when the key was turned. High intake air temps will kill any motor unless it is designed for it.get an inter-cooler if your going to run boost.
2000 Contour SE,All stock and lots a fun,But I have plans
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Originally posted by warmonger:
Perhaps a magnetic field coupling since the turbine is so light? That way it wouldn't actually be in contact with the turbine.
war...
So in layman's terms, use a magnet to spin the turbine at low engine rpms? I am assuming an electro-magnet, or could it work only using the polar characteristics of the magnets?
Contour--It will make a master mechanic out of you!
95 LX MTX Bolt-ons
95 Neon SOHC ATX
77 Dodge Powerwagon-more displacement than my Neon, Contour, and wife's Saturn---combined!
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Originally posted by Oeneus:
Originally posted by warmonger:
Perhaps a magnetic field coupling since the turbine is so light? That way it wouldn't actually be in contact with the turbine.
war...
So in layman's terms, use a magnet to spin the turbine at low engine rpms? I am assuming an electro-magnet, or could it work only using the polar characteristics of the magnets?
You would have to have some permanent magnetic areas on your compressor wheel, then use electromagnetic field coils surrounding the compressor housing. These would be swithed on to spool the compressor/tubine up to speed rapidly but would have to be shut off to prevent them from actually slowing the compressor wheel down at very high turbo speeds.
You could just use a conventional electric motor armature located centrally...between the turbine and compressor, sort of where the bearings are now and then shut off the motor as the exahust volume goes up. However, the turbo has enough mass already and would be VERY massive with that kind of armature in the middle. That is why I was thinking permanetly magnetic blades on the compressor with the actual compressor housing having field coils all through it. Exhaust side is too hot.
Still, it would probably be smarter to continue working on Lighter Mass components for the turbine/compressor wheels so that less exhaust would be required to spool the compressor RATHER than adding more energy to turn an already massive turbine.
war...
Former owner of '99 CSVT - Silver #222/2760
356/334 wHP/TQ at 10psi on pump gas!
See My Mods
'05 Volvo S40 Turbo 5 AWD with 6spd, Passion Red
'06 Mazda5 Touring, 5spd,MTX, Black
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