Power Steering Assist - Feedback requested from owners with completed kits

bradr

Well-Known Member
A group of questions for owners who have completed Goblins:
  1. Stock power steering - installed or removed / disconnected?
  2. Are you happy with your current setup?
  3. If you could change the stock Cobalt power steering assist, describe in detail what you would want changed (ie. less assist at idle, less assist across the whole range, fixed assist level at all speeds, etc.) If you know speed thresholds where you would want any changes, include them as well.
I gather that the level of assist might be a bit too much for a Goblin that is half the weight of a Cobalt. I want to use this feedback to determine if I should invest time into creating a solution for this "issue". Thank you in advance for the feedback!
 

Ross

Goblin Guru
1. I kept the Cobalt power assistance.
2. I find that I have to concentrate on holding my lane when I drive my goblin.
My goblin steering gives little feedback to the driver. The goblin has about a foot shorter wheelbase than the Cobalt, which makes it quicker to turn, and a bit more difficult (twitchy, darty) to drive straight.
3. Probably need to do the changes that Bruce and George did:

Bruce removed his power assist from the steering.
George reduced the internal drag of the steering box.
I kept the steering column adjustment from the Cobalt.

There is an adjustable steering controller, if you are willing to swap out the Cobalt unit. I have read about it here somewhere.
The Cobalt unit is designed to be used in other Chevy vehicles, and I have heard that power steering unit asks the BCM which car it is in, and then uses 1 of the 8 pre-defined power assist profiles that it has stored in the power steering unit. HP Tuners doesn't have hack into the power steering unit.

Of course I could go back and double check that my goblin's wheel alignment is still valid, and I could play with the steering caster angle too, but I think that I would get more results if I made the Bruce and George changes first.

I am curious what other goblin owners will report on this, as there is a lot of customization to these things.
I should mention that I am using wider tires than most, with wheel spacing that maintains the inside edge of the tire, but results in the car being 8" wider than a stock goblin. Also have 125 lbs/inch springs in the front and 300 lbs/inch springs in the rear. 0.7 degrees camber rather than the recommended 1.5 degrees, as the wide tires needed the reduced angle to touch the road.
 

bradr

Well-Known Member
Thank you for the replies thus far. I should have explained better where I was coming from. I have done the research and understand some have disconnected / removed the power steering. I understand the Saturn Vue PSCM and others support an external adjuster.

The question I want indirectly answered by the three questions in the first post is: If you could substantially change the assist profile of the stock PSCM, would that be of value or not. Example: if the least amount of assist is still too much, then there is no value in keeping the power steering.
  • My concern removing the power steering is that I will not like the force required to maneuver in a parking lot.
  • My concern using the PSCM from a Vue is that you have fixed steering assist across the whole speed range.
I want to maintain variable assist across the entire speed range so I can easily maneuver in a parking lot and still have a "sporty" and "connected to the road" feeling while driving. I believe that none of the 8 profiled loaded into the PSCM are going to be useful - none of them are for a 1500 pound car. I believe scaling and constraining or remapping the speed input to the PSCM from the BCM is the ticket. I just want to know if I am wasting time if ultimately it will still be too much assist.

Bruce: Do you now wish you had any assist at low speeds?
Ross: Have you tired unplugging your PSCM to see how the Goblin operates with no assist?

-Brad
 

Lethalcast

Well-Known Member
Mine went out a few times and I didn't like it at all. At speed the power steering has no noticeable assist it seems like but I didn't drive mine at higher speeds to check this. Would be interesting to know if it does assist at say 50+ mph. It's at low speed you'll be glad you have it imo.
CHEVY COBALT ELECTRIC POWER STEERING MODES
The General Motors EPS system has several modes of operation:
* Normal mode -- Left and right assist is provided in response to inputs and vehicle speed.
* Return mode -- Used to assist steering return after completing a turn. Feedback from the steering position sensor prevents the EPS system from "overshooting" the center position.
* Damper control mode -- Used to improve road feel and dampen kickback. This mode typically kicks in at higher vehicle speeds.
* Protection mode -- Protects electrical components from thermal damage and excessive current flow if the steering is held all the way to one side in the lock position too long.

It would be great to know some speed references on how and when the system works and at what assist level and speed. I also found this little tidbit of information that I'm unsure about but would be nice to know if it pertains to our system.
"Also note that the steering position sensor and torque sensor calibration procedures should be performed after an alignment. Complaints such as poor or uneven center "feel" or return to center can also be corrected by performing these procedures."
 
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Lethalcast

Well-Known Member
I did replace my cobalt ss one with one from an hhr from a junkyard. It was a different part number and to me I noticed a difference in driving but I have no way to know for sure.
 

Ross

Goblin Guru
Brad,

You obviously have been studying this. I have driven the car without power assist powered up, and the extra drag of the motor removes more steering feedback, making the car harder to stay in a lane, and harder to park. I prefer the car with power steering.
 

JSATX

Goblin Guru
Well to each his own of course. I didn’t build the goblin to be comfortable. I hated the power assist specifically for the same reason most like it, it dampens the road feel too much. Yes the assist makes highway driving easier, but if your car is darting around too much that sounds like an alignment issue to me. I removed the electronic motor completely and printed a cap with the oring and wouldn’t go back.
 

Christopher Sanchez

Well-Known Member
1 Hands down I enjoy the car more with power assist for slow speeds, feels a bit light up front during spirited back road driving. (I have zero track experience) It requires a lot of force to turn at slow speeds.
2 I feel the power steering works fine for casual driving.
3 Id be interest to see how the car felt with 50% assist once you're up and moving. The EPS just adds a "feeling of lightness" to the already really light front end of these cars.
 
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