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Old 02-19-2008, 01:55 PM   #7 (permalink)
trebuchet03
MechE
 
Join Date: Dec 2007
Location: Bay Area
Posts: 1,151

The Miata - '01 Mazda MX-5 Miata
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Quote:
Originally Posted by Daox View Post

The Honda link was interesting, but obviously not focused on fuel effeciency. I don't think my power steering is sucking up anywhere near 5 horsepower, let alone 8.5. Those numbers must be at peak rpms. I didn't read all the replies to the original message, but it sounds like he is still running the pump all the time since he just has it on a switch. I'd definitly want some sort of circuit to turn it off when not needed.
There's some important info in there though....

Quote:
There are two thick wires in one connector - one red and one black. You must remember that the pump draws a lot of current (allow for 60 amps), so you need heavy duty wiring. All the parts are commonly available from most automotive electrical suppliers. We used 8 gauge wires with an 80 amp circuit breaker. We mounted the Circuit Breaker beside the shifter so it is within easy reach of the driver so if he wishes, he can turn it on and off, but for a street car you would probably need to also use a high power relay to switch the Steering pump motor on after the engine is started. I don’t want to get too carried away as my electronics knowledge is very basic…
The pump draws 15A with no steering input, and 30-50A when turning the wheel quickly.
Sounds like it stays on to keep the system pressurized... 50A is about 1hp of energy... not sure how that translates to engine power, but that's a lot of freaking energy going into power steering....
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