89-05 ELECTRIC Steering Rack, Adjustable!!!
#22
Looks like a Saturn/GM column modified to a Miata one with the PSCM attached. If that is the case I know the GM modules use information sent through a low speed network for it to know vehicle speed in order to control the assist amount.
Not sure of how MS uses CAN communication but if it is either a 0-2.5 volt pull up or down then maybe it could talk to a MS ECU.
Not sure of how MS uses CAN communication but if it is either a 0-2.5 volt pull up or down then maybe it could talk to a MS ECU.
#23
Now I want one. I really like the idea of being able to have depowered and assisted steering in the same car. Being able to add assist when driving around in parking lots, or when my mom wants to drive my car or if I'm trying to drink a beer(jk) is very appealing. Is the rheostat something that is readily available? Just curious because I work with voltage adjust rheostats and they often go bad, but different environment for sure.
#25
For those concerned about "feel", there is nothing inherent to EPS that reduces feel beyond multiplying an input torque signal. EPS replaces the torsion arm in the PS valve body with a strain gauge, which is an opportunity to improve stiffness of the assembly for a given input torque (note this opportunity is best taken advantage of with the motor co-located with the rack). Lag, filtering, and damping may exist depending on the electronics used or calibration, for better or worse. S2K/RX8 have excellent steering and some of the first generation EPS racks. On the other hand, BMW reduced the effective outboard geometric arm between the contact patch and steering axis on the F30, which, so BMW says after increasing it in the G20, is why the steering feel was so bad on the F30 (I suspect the variable rack didn't help). I wonder if their decision was to reduce power requirements (and improve efficiency) from the electric motor.
This is a great offering, HPS is annoying to package and requires dealing with a (very) flammable fluid in the engine bay.
Ref:
https://jalopnik.com/the-engineering...ing-1830257906
https://garrett-engineers.com/cases-...o-fluids-burn/
I too am wondering about information than can be sent to the ECU for idle control and speed sensitivity (however a bit weary to trust the ECU to do this safely).
Three questions:
Thanks,
Chris
https://www.facebook.com/GuarinoWatsonRacing/
This is a great offering, HPS is annoying to package and requires dealing with a (very) flammable fluid in the engine bay.
Ref:
https://jalopnik.com/the-engineering...ing-1830257906
https://garrett-engineers.com/cases-...o-fluids-burn/
I too am wondering about information than can be sent to the ECU for idle control and speed sensitivity (however a bit weary to trust the ECU to do this safely).
Three questions:
- Does the system retain the OEM computer from the booster (and corresponding safety features)?
- I think I can see the upper oiled sliders in one of the pictures - are the Mazda OEM collapsing stages maintained?
- What happens to the ignition switch/lockout?
Thanks,
Chris
https://www.facebook.com/GuarinoWatsonRacing/
Last edited by cwatson; 02-14-2019 at 07:51 PM.
#27
#31
Has there been any follow up on this where someone has installed it and configured it to work with MegaSquirt to do variable assist based on VSS? Or to idle-up when steering assist is engaged? This is an appealing item for one of my cars, but I would ideally want to be able to dial it in for control by the MS3.
Last edited by jnshk; 08-01-2019 at 10:00 AM. Reason: Speeling.
#33
Electric Power Steering
FYI, I bought/installed one of these units in our endurance race car and this past weekend was our first outing with it at Hallet. Out of our 4 drivers, all liked it except one guy and he would turn it off during his stint. Its notable that the driver that didn't use it was also driving another miata at the event with manual steering. His comment was he would over correct if the car got loose with the power steering turned on.
Overall, very happy with the electric power steering! I was concerned about amp draw being too high but it was not an issue. We ran the adjustment at the minimum setting and the three drivers that used it were very happy!
Overall, very happy with the electric power steering! I was concerned about amp draw being too high but it was not an issue. We ran the adjustment at the minimum setting and the three drivers that used it were very happy!
#34
Has anyone tried this and driven at say 130mph over an uneven road with cambers?
OEM EPS systems have a VSS based damping map to make up for the inherent lack of natural damping that you get in an HPAS system from having to push a viscous fluid around.
I'm very interested to see how this can work without VSS to both be stable at high speed and not over filtered and over damped at low speed.
OEM EPS systems have a VSS based damping map to make up for the inherent lack of natural damping that you get in an HPAS system from having to push a viscous fluid around.
I'm very interested to see how this can work without VSS to both be stable at high speed and not over filtered and over damped at low speed.
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