Electric Water Pump

[nivvy]

Hers some thought from the moparts guys.... 

It seems worth it to them... the guys that run it.... pick up a little E.T. and says cools down real fast

http://board.moparts.org/ubbthreads/showflat.php?Cat=0&Number=4064241&an=0&page=0&gonew=1#UNREAD

[dodge freak 2]

I always thought that too but then if my car is idling and I flip my electrical fan on, I can hear the motor getting lug down a bit. So it must be sucking 5 HP.

The hot tip used to be to get a switch in the pass. area to flip off the alternator off for the run. Must have been worth some gain because all the old mag. used to post about doing it and many did.

[quagmire]

I dont know how this applies to older vehicles like ours, but I have seen comparisons with dyno plots that were used to test whether underdrive pulleys are actually worth the headaches they cause.  They tested a late model performance car stock like a Mustang or Camaro with belts on, with all belts off, and then with the UDP.  They only gained like 3-5 horsepower with no belts, and like 1-2 horsepower with the UDP.  So I am not too sure how much horsepower eliminating just the water pump could possibly free up.  Also, their is no way a 57 amp load only eats one horsepower.  Even a small load like a rear defroster would cause a fuel injected car to stall if they did not recieve an input to let the PCM know it is on and to increase the idle accordingly.  SPL guys have high output alternators that require them to run the engien at over 2000 RPM and you can still see the engine lug down at that speed when the alternator is full fielding on a bass hit. 

[cudabob496]

I dont know how this applies to older vehicles like ours, but I have seen comparisons with dyno plots that were used to test whether underdrive pulleys are actually worth the headaches they cause.  They tested a late model performance car stock like a Mustang or Camaro with belts on, with all belts off, and then with the UDP.  They only gained like 3-5 horsepower with no belts, and like 1-2 horsepower with the UDP.  So I am not too sure how much horsepower eliminating just the water pump could possibly free up.  Also, their is no way a 57 amp load only eats one horsepower.  Even a small load like a rear defroster would cause a fuel injected car to stall if they did not recieve an input to let the PCM know it is on and to increase the idle accordingly.  SPL guys have high output alternators that require them to run the engien at over 2000 RPM and you can still see the engine lug down at that speed when the alternator is full fielding on a bass hit. 

57A x 14.9V = 798 Watts
798 Watts / 745.7 watts/hp = 1.1 HP

[quagmire]

It doesnt work that way in the real world, only on paper.  It isnt a perfect conversion. After heat and friction that HP draw increases it quite a bit.  If it only sucked that little amount of power at that current output their would be no reason for increasing idle speeds and you wouldnt feel the engine drag down so much when you used certain accessories like power windows, defrosters, and even the blower on high.  All of those combined might draw half of that 57 amp per 1 horsepower rating from that formula.  In fact, alternators are generally anywhere from 45-65% efficient, so a general rule of thumb is that an alternator will draw 1 horsepower per 25 amps.  This is a generalization, because as output increases efficiency decreases.

[cudabob496]

It doesnt work that way in the real world, only on paper.  It isnt a perfect conversion. After heat and friction that HP draw increases it quite a bit.  If it only sucked that little amount of power at that current output their would be no reason for increasing idle speeds and you wouldnt feel the engine drag down so much when you used certain accessories like power windows, defrosters, and even the blower on high.  All of those combined might draw half of that 57 amp per 1 horsepower rating from that formula.

Well, I didn't address effeciencies.  Alternators are very efficient at converting mechanical engery into electrical. So, assuming an alternator is 90% efficient, then a 57 amp load on your alternator would draw 1/.90 = 1.1 horsepower from your engine. Don't assume numbers based on what an engine does at idle. At idle, many alternators are very poor at producing power, and the voltage can drop quite a bit. By the way, putting numbers on paper put a man on the moon in 1969.

[quagmire]

Yeah, but alternators are only 45-65% efficient regardless of engine RPM, and that will decrease with output.  Anyhoo, I'd like to see a real dyno plot of a full street car with an electric water pump and a mechanical.  I'm sure theyd benefit a race car slightly since they have no alternator, but I seriously question their use on street cars.

[dodge freak 2]

Did you know some people think no man has made it to the moon yet, and NASA fake it ?? I haven't gone yet to see if a flag is really on the moon.

Its very true you can hear the motor slow down if you use even a power window switch. The only way not to lose power from the ala. is to cut off the ala. during the run, which is easy to do. I believe some new cars even do that for a short time when the gas pedal is floored. We would have to rig a switch up--and remember to flip it back on after the run

[nivvy]

I posted a link on another site with a guy and his camaro adn he picked up 10 RWHP on his dyno run slapping on a meziere....at high rpm of course

If I dont like it I'll slap on my maechanical march setup and sell the meziere....

Alot of people arent sold on them to try them but for most people who have used them swear by them 

I'll know soon enough I guess....

[cudabob496]

All the engine shootouts in the car magazines use electric water pumps.  This subject, like many others in hot rodding, is undergoing an evolutionary process, just like the discussion on whether or not to use synthetic oil.

[cudabob496]

Did you know some people think no man has made it to the moon yet, and NASA fake it ?? I haven't gone yet to see if a flag is really on the moon.

Its very true you can hear the motor slow down if you use even a power window switch. The only way not to lose power from the ala. is to cut off the ala. during the run, which is easy to do. I believe some new cars even do that for a short time when the gas pedal is floored. We would have to rig a switch up--and remember to flip it back on after the run

Just don't tell me Pro Wrestling is fake!

[nivvy]

All the engine shootouts in the car magazines use electric water pumps.  This subject, like many others in hot rodding, is undergoing an evolutionary process, just like the discussion on whether or not to use synthetic oil.

Very True... I read an article d.i.c.k. Landy says 10-15 pickup

How bout this..... Im gonna put on my meziere for "bling" factor and when I pop my hood the mustang boys get  cause they see my motor and say ... he's gotta electric water pump too.......... 

Ill be the test dummy here for the street guys... people who use them swear by them ... I'll post results in the summetime  hopefully it goes well 

[nivvy]

Just don't tell me Pro Wrestling is fake!

 

[cudabob496]

Very True... I read an article d.i.c.k. Landy says 10-15 pickup

How bout this..... Im gonna put on my meziere for "bling" factor and when I pop my hood the mustang boys get  cause they see my motor and say ... he's gotta electric water pump too.......... 

Ill be the test dummy here for the street guys... people who use them swear by them ... I'll post results in the summetime  hopefully it goes well 

Looking forward to it. If I switch over, I will do the same.

[cudabob496]

It doesnt work that way in the real world, only on paper.  It isnt a perfect conversion. After heat and friction that HP draw increases it quite a bit.  If it only sucked that little amount of power at that current output their would be no reason for increasing idle speeds and you wouldnt feel the engine drag down so much when you used certain accessories like power windows, defrosters, and even the blower on high.  All of those combined might draw half of that 57 amp per 1 horsepower rating from that formula.  In fact, alternators are generally anywhere from 45-65% efficient, so a general rule of thumb is that an alternator will draw 1 horsepower per 25 amps.  This is a generalization, because as output increases efficiency decreases.

Well, even if alternator effieciency is 50%, 57 amps will still only consume about two 2 hp.