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Alright, so in another step to pioneer our car platform. I was thinking about converting from a mechanical pwr steering system to a electric power steering system. It's not very common in most cars, however, a few cars do come with electric power steering (i.e. 2nd. Gen Toyota MR2). A lot of off-road/ rock crawler guys use electric opposed to mechanical.
Now there is an obvious advantage to using a electric pump over a mechanical, which is cutting down the parasite drag that the mechanical pump produces thus lower the hp./tq. The also advantage that I see is that the stock pump is sluggish if anyone hasn't noticed yet. Perhaps chaning to a electric pump would solved this issue a bit.
The pump itself runs off a 12V supply, however it draws alot of amps. About 70-80 Amps @ 12V while it turned full to either side, less while the wheel is straight or the car is moving since the wheels are in motion requiring less effort.
Thus knowing this we know we need a circuit breaker and a relay, both have to be heavy duty. The relay would have to be a heavy duty one made by Bosch (Single Pole, Single Throw) rated at 75 amps (Part # 0 332 002 156). The circuit breaker is a high current one made by Buss rated at 80 Amps, self-resetting breaker, (Part # 181080F). Now this is important in case of line spikes, which could reset the breaker so there is need to have a self-resetting one so it does not present a safety hazard at the track.
The pump has another 4 wires beside the pwr and ground that are PWN controllers, which I think I could use to control the pump via my Haltech E8 to relate the vehicle speed sensor to speed up or slow down the pump.
***NOTE***
It would be perfectly fine to run the pump at full speed, the PWN control is not a must.
Incase you are inclinded and want to know how the pump is controlled.
How To:
Toyota MR2 Power Steering System
Installing the Electro-Hydraulic Power Steering System
Plan:
2nd Gen Toyota MR2 PWR Steering Pump
Bosch Relay 75amp (Part # 0 332 002 156)
Buss HC Circuit Breaker (Part # 181080F)
Let's discuss the pro's and cons :wavey:
Now there is an obvious advantage to using a electric pump over a mechanical, which is cutting down the parasite drag that the mechanical pump produces thus lower the hp./tq. The also advantage that I see is that the stock pump is sluggish if anyone hasn't noticed yet. Perhaps chaning to a electric pump would solved this issue a bit.
The pump itself runs off a 12V supply, however it draws alot of amps. About 70-80 Amps @ 12V while it turned full to either side, less while the wheel is straight or the car is moving since the wheels are in motion requiring less effort.
Thus knowing this we know we need a circuit breaker and a relay, both have to be heavy duty. The relay would have to be a heavy duty one made by Bosch (Single Pole, Single Throw) rated at 75 amps (Part # 0 332 002 156). The circuit breaker is a high current one made by Buss rated at 80 Amps, self-resetting breaker, (Part # 181080F). Now this is important in case of line spikes, which could reset the breaker so there is need to have a self-resetting one so it does not present a safety hazard at the track.
The pump has another 4 wires beside the pwr and ground that are PWN controllers, which I think I could use to control the pump via my Haltech E8 to relate the vehicle speed sensor to speed up or slow down the pump.
***NOTE***
It would be perfectly fine to run the pump at full speed, the PWN control is not a must.
Incase you are inclinded and want to know how the pump is controlled.
How To:
Toyota MR2 Power Steering System
Installing the Electro-Hydraulic Power Steering System
Plan:
2nd Gen Toyota MR2 PWR Steering Pump


Bosch Relay 75amp (Part # 0 332 002 156)

Buss HC Circuit Breaker (Part # 181080F)

Let's discuss the pro's and cons :wavey: