Quote:
Originally Posted by Ecky
Really glad it worked out for you! There are a lot of Honda folks on here, and I'm certain someone else will eventually follow your lead with this swap.
For what it's worth, the EPS rack is also great for manual conversions, there's a lot less resistance than with a hydraulic rack, but there are some things you need to do to it to make it work. Simply unplugging or even unbolting the EPS motor is going to leave a stiffer than necessary manual rack because the motor connects to the rack via a worm gear. The gear turns very easily from the motor side but not the other way around. Turning the rack without the motor spinning results in a lot of resistance unless you remove the worm gear as well.
See here: https://en.m.wikipedia.org/wiki/Worm_drive
Put another way, Honda's EPS racks have a large reduction ratio and unless the worm gear is removed along with the motor, a manual conversion with these racks leaves a lot of friction and drag, similar to how looping the lines in a hydraulic rack still results in high steering effort.
Q. Why would you ever want to do a manual conversion on an electric rack which is virtually free in terms of economy?
A. Due to the above property of worm gears, relatively little steering feedback is able to get back to the steering wheel. |
That is really great information! I actually noticed that when the front tires are off the ground it is still quite hard to steer, similar to the feeling of if I was turning a hydraulic rack without the engine running. I wondered if it was drag from turning the motor, but then I remembered that the motor turned very easily when I had to take it out to get the rack in. I would say that with the front tires off the ground, the steering effort is the same as or slightly higher than with the tires on the ground and the EPS active, but definitely more drag than the OEM hydraulic rack with no oil in it.
As for converting the EPS rack to a manual rack, there is one little thing that you are forgetting: The torque sensor play. The torque sensor would introduce a little bit of play in the steering also because you are basically turning through a spring. I can't feel the play while driving, but if EPS isn't active and the car is sitting still, the play can be felt a little while turning. It isn't bad at all, it just basically feels like you are turning through a spring, but not that bad. But with EPS active, the play can not be felt at all.
But if you are going to go through the trouble of converting an EPS rack to manual for the purpose of achieving more steering feel and more precise steering, you may as well find some way to get rid of the play in the torque sensor or make a solid shaft with no torque sensor for the best possible results though.