Electric water pump
And also FWIW I stuck with the stock timing set which is plenty strong for most applications, imho. When I changed cams in 2005 I just replaced the chain with a new stocker.
--Alan
Alan's experience of raised coolant temps at cruise supports that it is not moving 35gpm at say a 2400rpm cruise like the stocker does.
Again I am not trying to say electrics are bad, just want the junk science arguments for their use to end. It serves everyone well for us to actually understand how things work.
I will say that IMO there is an "efficiency gain" with the electrics in having the water accelerated in the system. When racing the stock pump is not just pumping 66gpm at 4800 engine rpm it is accelerating that water from say 20gpm to 66gpm.
Sure the electrics have a nicer impeller but these guys are suggesting an efficiency gain of an under .2hp pump doing more work than an 11hp pump despite two inefficient energy form changes from rotation to electricity back to rotation. IMO the efficiency of not having to accelerate the water is greater then the impeller difference.
I don't know if anyone can test the rpm of an electric as it is turned on but it would be interesting to know how long it takes to come up to steady speed and how long it takes for flow to actually peak, not that any of that matters performance wise, not like it is going to take minutes and affect cooling. Just again I like to understand things.
As I said before idles change when you hookup to a dead vehicle to jump it there is practical proof any of us should have experienced of varying load to the belt.
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As I said before idles change when you hookup to a dead vehicle to jump it there is practical proof any of us should have experienced of varying load to the belt.
Some may chose a EWP because they feel it "flows" more than a mechanical pump. As discussed it may at some or most of the capable RPM range of a LT1.
I would argue the majority do it for increased HP. Removing the WP from "mechanically" being driven by the motor is just like droping the belt while running down the 1/4 mile. You will go faster because the motor is not "mechanically" aka parasidic drag (jb442 said it best)running the accessories (power steering, AC, alternator). Yes a EWP does draw power from the alternator thus increasing it's load on the motor BUT that "load" is a very small fraction of HP a mechanical pump draws.
I only know from real world expierience. Have a EWP (Meziere 55 gph)on for 12+ years on my B-body with about 80k miles on the pump now. For me mechanical pumps failed and killed Optis and when the car went out of warrenty I swapped to EWP. No warning lights or buzzer, just monitor my gauge just like I do on all my cars. Have a spare EWP I bought used in the trunk. I keep a basic tool kit in the trunk all the time and a swap would take 20 min tops. A quick bleeder and small tube to run into over flow tank and bleeding is plug & play either in the garage or stranded on the road somewhere.
I would not, and have not, hesitated in taking the car on any long drive
So...based on the many replies there are "multiple" reasons to use a EWP. All by choice and just like shoes....one size does not fil all :-)
This ^ it?
Says 55gpm and it seems to have a nice price, also it says that it has a 10,000 hour life expectancy. Couple other ones were around 2000-3,000 hour life expectancy that I remember. Maybe yours is older and they now make them 55gpm.
Last edited by FormulaJoe; Jan 24, 2012 at 12:11 AM. Reason: Spelling





