electric powersteering pump??? asap
I thought those were MR-2's?
I wonder if all hybrid/electric cars have to use an electric hydraulic pump?
I know Gm is using an electric steering rack so as far as I know that won't work.
I wonder if all hybrid/electric cars have to use an electric hydraulic pump?
I know Gm is using an electric steering rack so as far as I know that won't work.
Ok, it doesn't look too good for the MR-S Electro Hydraulic Power Steering unit. It uses a 100 amp relay so it's current consumption is going to be pretty high. You may even need a 2nd battery. Second, it appears to need an optical circuit in the steering column to read it's position.
On the plus side they can be bought for around $65.
http://www.cameronsoftware.com/ev/EV...g_Install.html
On the plus side they can be bought for around $65.
http://www.cameronsoftware.com/ev/EV...g_Install.html
Last edited by JasonWW; Apr 14, 2008 at 02:58 AM.
Some more info:
Electro-Hydraulic Power Steering (EHPS)
EHPS was developed as a temporary solution while the automotive industry slowly migrates to complete Electric Power Steering (EPS).
Since these units are 12v, they require a lot of current, especially at peak times. The accessory battery should be sized to handle these peak loads, or an ultra capacitor can be used to avoid loading the DC-DC system with this heavy load.
The advantages to this system are that it is OEM quality in an integrated package.
The drawbacks to this system is that it will require heavy wiring (60-70 Amps peak), loads the DC-DC system, and will require a system so that it only turns on when the steering turns.
EHPS units are available from:
1988 Fiero
1991 Toyota MR2
New MINI
Other European, South American cars: (Vaxhaul Astria, Renault Clio, Citroen Saxo, Peugeot 307, VW Polo, VW Seat Ibiza)
- - - - - - - -
Electric Power Steering (EPS)
EPS uses 100% electricity to run the power steering. It is more common in Europe, but is used on one or two North American cars:
Honda Acura NSX
Honda S2000
Honda Hybrid Insight
Honda Civic Sedan
Saturn Vue SUV
Saturn Ion Sedan
EHPS was developed as a temporary solution while the automotive industry slowly migrates to complete Electric Power Steering (EPS).
Since these units are 12v, they require a lot of current, especially at peak times. The accessory battery should be sized to handle these peak loads, or an ultra capacitor can be used to avoid loading the DC-DC system with this heavy load.
The advantages to this system are that it is OEM quality in an integrated package.
The drawbacks to this system is that it will require heavy wiring (60-70 Amps peak), loads the DC-DC system, and will require a system so that it only turns on when the steering turns.
EHPS units are available from:
1988 Fiero
1991 Toyota MR2
New MINI
Other European, South American cars: (Vaxhaul Astria, Renault Clio, Citroen Saxo, Peugeot 307, VW Polo, VW Seat Ibiza)
- - - - - - - -
Electric Power Steering (EPS)
EPS uses 100% electricity to run the power steering. It is more common in Europe, but is used on one or two North American cars:
Honda Acura NSX
Honda S2000
Honda Hybrid Insight
Honda Civic Sedan
Saturn Vue SUV
Saturn Ion Sedan
Here is an excellent article on electric power steering.
http://www.autospeed.com/cms/A_0484/article.html
What we've been talking about in this thread is referred to as a Hybrid Hydraulic/Electric Power Steering System. This is by far the easiest and cheapest setup for our F-bodies.
Steering Wheel Input Mode is what the MR-S uses and is not for us.
Steering Load Mode is what the Renault Clio uses and is easily adapted to many types of autos. These types of pumps are what we need to focus on. I'll try and compile a list of vehicles using this style of pump. So far we only know of the Clio.
A smart place to look is for converted electric cars. They usually had hydraulic systems with a pump on the engine, but after converting to electric they need an EHPS system that is easily integrated to the old hydraulic steering racks.
http://www.autospeed.com/cms/A_0484/article.html
What we've been talking about in this thread is referred to as a Hybrid Hydraulic/Electric Power Steering System. This is by far the easiest and cheapest setup for our F-bodies.
Hybrid hydraulic steering systems use an electric motor to drive the hydraulic pump, rather than having the pump driven directly by the engine. This approach allows the steering effort to be easily controlled by varying the pump speed. Because flow can be better matched to actual requirements, the power drain is reduced.
The control approach that is taken can be of three types -
Driving Mode - where driving conditions (such as city, country, highway, etc) are automatically judged with appropriate levels of assistance then provided.
Steering Wheel Input Mode- where the speed of the steering wheel movement is used to determine the degree of assistance required.
Steering Load Mode - where demand for power assistance is indicated by the counter-pressure of the hydraulic fluid, sensed through variations in the motor current load.
The control approach that is taken can be of three types -
Driving Mode - where driving conditions (such as city, country, highway, etc) are automatically judged with appropriate levels of assistance then provided.
Steering Wheel Input Mode- where the speed of the steering wheel movement is used to determine the degree of assistance required.
Steering Load Mode - where demand for power assistance is indicated by the counter-pressure of the hydraulic fluid, sensed through variations in the motor current load.
Steering Load Mode is what the Renault Clio uses and is easily adapted to many types of autos. These types of pumps are what we need to focus on. I'll try and compile a list of vehicles using this style of pump. So far we only know of the Clio.
A smart place to look is for converted electric cars. They usually had hydraulic systems with a pump on the engine, but after converting to electric they need an EHPS system that is easily integrated to the old hydraulic steering racks.
Last edited by JasonWW; Apr 14, 2008 at 04:50 AM.
Teching In
Joined: Apr 2008
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I have a friend that made an MR-s(2000up MR-2) pump work on his rx7, the steering signal input is not necessary just run the pump on a high amp circuit and you should be fine, as long as the pump runs you should have steering pressure.
The Clio pump senses the pressure differential and speeds up when you turn the wheel. I think the rest of the time the motor turns at a lower speed making it run more effeciently and cooler.
I'm new to these things so I'm not sure.
