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I was wondering how much hp my power steering cost. Also, here's probably a dumb question: why can't you run a DC motor to pull your power steering like you can for your water pump?
 

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1st question- your PS pump takes about 1-2 hp from articles I remember reading, cant say that is accurate, but sounds good to me.

2nd question-sounds like you may have found an idea for a new market of speed parts, now all you have to do is build it and they will come.
 

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I sure hope you're right. I must have been mistaken but thought I had heard somewhere that power steering robs around 20 hp. If it's just 1 to 2 hp, that's probably why I haven't heard of anyone using an electric motor. I would still like some more posts from you other guys that have knowledge in this area. Thanks
 

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There are already some production cars using electric power steering pumps (the new Mini Cooper uses one) but I have never seen them offered to the aftermarket yet, sounds like you had better jump on this one.
 

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They use power steering in NASCAR (Gordon lost his this weekend).

Unlike power brakes, power steering is RPM dependant. Once you make so many RPM, it's all neutral (as far as I understand). I don't think it robs your engine of that much... but I could be wrong. I think on a V configuration motor we lose more to volumetric efficiency and valve train power loss.
 

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On my 68 mustang taking off the power steering belt at the track gives me about 1mph more and shaves about a tenth off the ET.If you don't think these old pumps are hard to turn try it by hand some time,and then imagine it at 6000rpms!I estimate this to be close to 10 hp.I think the newer plastic style take less power to turn,at least it feels that way by hand turning.
 

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This is why the automotive industry will be converting to 42 volt charging systems. This will allow them to run electric water pumps, rack and pinion, air pumps, a/c pumps. The only accesory that will be belt driven will be the large alternator with a cog belt most likely to be able to handle the load. But just keep in mind that energy cannot be created or destroyed. By using more electrical accesories the alternator must work harder causing a loss of Horsepower through the alternator.
 

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as i see it, you can only temporaraly remove the load the the engine by using a DC engine to drive those things, and thats if you remove the belt to the alternator too ..

As i have unserstood it by reading alot of articles about future cars with 48V systems, they are doing this bqs its more easy to route electrical cables in the car than hydraulic or mechanical systems, but you will still loose some power, the alternator, DC motor and cables wont run 100% efficiently
 

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I have often wondered how much hp the alternator takes to run when you install a big electric fan setup.It probably takes up a lot of the hp you gain by taking off the fan.When I put an electric fan on my 68 mustang I could not get the fan belt to stop squealing,deglazed the pulleys tried a couple different belts nothing worked so I switched to a clutch fan.
 

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I'm not sure how mch power it does cost but, when my PS pump had to be replaced I drove it for a short while without it (66 Mustang with 289 and c4). I could tell the difference for sure. If i had to guess, I would say about 10-15hp.
 

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I can see one big advatage to use alectric motors to drive the fan, Ps pump or Waterpump, and it is that you can keep them spinning at their optimum RPM, not too fast so they cavitate or too slow so they doesent work well, ex the fan, when you are standing still you want maximum airflow from the fan, but it doesent spin as faast, and while you are moving it spins faster then nessesery and robbing hp and fuel, the same for the PS pump.
 

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1 horsepower is equal to abou 750 watts of electric power. Assuming the alternator is about 90% efficient, and running at 14.5v, a 45 amp draw from the alternator requires 1 engine hp. So, running 30 amp electric fans uses about .66hp, running an electric water pump (about 10 amps I think) uses .2hp. If the power steering actually needs 2hp to run, it would have to pull 90 amps off the alternator to turn it. However, that 2hp was probably at like 5500rpm, but the pump only needs to turn about 2000-2500rpm, so the power requirements would be way less, like 20-30 amps at most.

I think the major advantage to electric drive, as someone else mentioned, is you can run the parts at their optimal RPM, so at high RPM you still only require enough power to run the parts at low RPM.

There is one thing about mechanical fans that's kept me wondering. The power loss due to a mechanical fan is not to spin the fan, but to move air. It takes very little power to spin the fan (imagine if the blades were flat), so the of the 10hp loss from a big belt driven fan, I'd say 9.5hp goes to actualy moving air. Now, if a BIG electric fan pulls a 30 amp load, that means it is only consuming about .7hp of energy, .7hp of moving air, compared to 9.5hp of moving air. To me this means that if you are having cooling problems, the LAST thing you want to do is swap out your belt driven fan for an electric. Any thoughts?
 

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well I would tend to say in takeing 9.5 HP to turn that fan how many CFM is it moveing
I know that the black magic move 2800 CFM and use 13.9 amps

it sure feels like they move more air than a stock fan and at a whole .3 HP

take yor pick 10 hp or .3 with the .3 probally moveing more air, also take in mind that it will move 2800 cfm at idle when the car is sitting there. the stock fan doesn't do much at all at idle
 

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Generating electrical power is not very efficient, so all that calculating watts to hp isn't realistic. If it were you could hook up an alternator to power an electric motor to turn the alternator. Not! You would have a perpetual motion machine.

Another thought. You want the fan to pull the most air when ram air isn't available, like when the car is sitting still. This is also when the alternator is putting out the least amount of amps because of the idle RPM.

The electric motor for the PS pump sounds like a good idea. When racing, you could just flip a switch so there's no drain on the alternator. How about an AC clutch for the PS? Kinda like variable assist.
 

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Ok, just a thought but, could you use a electric fuel pump for your power steering ? Make sure to let me know if I'm way off base, ok.
 

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Cheater: I know generating electric power is not 100% efficient, but I think it's safe to say that modern alternators are at LEAST 75% efficient at turning that mechanical energy into electrical energy. I'll see if I can find some actual efficiency numbers on the web.

lordviper13: my whole point was that the belt driven fan requires 9.5hp to move the volume of air it does, where the electric only requires ~.5hp. Given the fan blade designs are equally efficient, the airflow should be proportional to the squaroot of the power consumed (four times as much power, twice as much airflow). I can see how at idle the electric fan would cool better because at idle the belt fan is probably using way less power than the electric fan. But I think the belt driven fan will outflow the electric at anything over 2500rpm.
 

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I was wondering how much hp my power steering cost. Also, here's probably a dumb question: why can't you run a DC motor to pull your power steering like you can for your water pump?
Don't know what you guys have been reading (or not reading_ but power steering uses 25-30 horsepower on most older cars. It makes a big difference--pull off the power steering belt next time you are at the strip and you will see. THEY DID NOT SEND THROUGH MANY OF THE TOP MUSCLE CARS OF THE 60'S WITH POWER STEERING DELETE FOR NO REASON.....BUD
 

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True, but people do say use the search function...a lot.
 

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1 horsepower is equal to abou 750 watts of electric power. Assuming the alternator is about 90% efficient, and running at 14.5v, a 45 amp draw from the alternator requires 1 engine hp. So, running 30 amp electric fans uses about .66hp, running an electric water pump (about 10 amps I think) uses .2hp. If the power steering actually needs 2hp to run, it would have to pull 90 amps off the alternator to turn it. However, that 2hp was probably at like 5500rpm, but the pump only needs to turn about 2000-2500rpm, so the power requirements would be way less, like 20-30 amps at most.

I think the major advantage to electric drive, as someone else mentioned, is you can run the parts at their optimal RPM, so at high RPM you still only require enough power to run the parts at low RPM.

There is one thing about mechanical fans that's kept me wondering. The power loss due to a mechanical fan is not to spin the fan, but to move air. It takes very little power to spin the fan (imagine if the blades were flat), so the of the 10hp loss from a big belt driven fan, I'd say 9.5hp goes to actualy moving air. Now, if a BIG electric fan pulls a 30 amp load, that means it is only consuming about .7hp of energy, .7hp of moving air, compared to 9.5hp of moving air. To me this means that if you are having cooling problems, the LAST thing you want to do is swap out your belt driven fan for an electric. Any thoughts?
Electric Power Steering
Electric Power steering consumes almost no power as soon as the car is moving. About 1/10HP

When the car is stopped < 1HP

This is one of the reasons new cars are getting EPS, fuel economy shoots up.

The numbers above are from actual measurements on a 3000lb Mustang with 225-50-17 tires up front.
 
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