Electric Power Steering

MGBV8 · May 31, 2018, 10:20:19 AM

Mike used a Chevy Equinox unit on his B. Not sure what he sent for the RM. Maybe the same?

BlownMGB-V8 · May 31, 2018, 11:10:08 AM

I'm pretty sure it is the same one he used for his own car. If Bruno sells a box for the Equinox that's probably it.

Jim

jjohanski · May 31, 2018, 11:45:29 AM

I have found out from other web postings that the new Bruno automatic control is not really automatic. It just emulates settings. For me that makes the Yaris column and ECU w/o ABS a better alternative as it controls input via a speed signal, from a hall effect source and not the CanBus. Others using it on various Fords have found this to work and with good self centering. If I was to use the Saturn/Equinox unit I would just use the regular Bruno knob.
This feedback on self centering is so subjective. I drive two different cars with EPS and they both self center but not anything like the MGB stock steering. Maybe all of these different approaches are ok.
I will probably try the Yaris setup.

cgill · June 01, 2018, 11:38:51 AM

I think I found my issue after a whole bunch of testing with both the new and modified column.

It's the black torque sensor piece that mounts directly on the column. The one in my modified column appears to be bad - it continuously turns to the left or right depending on which way I have the sensor mounted in the housing). Both torque sensors (new and old) work as they should when I test them in my new EPS.

So the question is, how do I remove this piece and replace it with the one from my new EPS without damaging the thing? I have to do this because the column on my current EPS has the correct splines welded to it to slide into my modified upper MG column (as you can see in the photo.

BlownMGB-V8 · June 01, 2018, 04:09:19 PM

Simplest thing to do Chris, since that one is bad, would be to see if you can budge it with a couple prybars. Doesn't matter if you break it, and in fact if the prybars don't work a hammer should. Then based on what you find there you can figure out how to remove the good one.

But here's the thing. There has to be a limited compliance coupling of some kind built into it, along with a strain gage. You may destroy the gage but you don't necessarily want to destroy the coupling. So you might have to chip away at it slowly to get to the inside. I'm just guessing the reason you don't want to tear it up is because of the tig weld. I kept the spline instead and didn't have that issue. Could be the heat destroyed it.

But the bottom line is that it had to go together somehow so you would think it could be disassembled... and it's already bad.

Good luck with it, I was wondering about that myself and didn't see any obvious way to do it.

The good news is that there is a workaround, the bad news is that it doesn't involve your nice tig weld.

Jim

cgill · June 01, 2018, 08:02:21 PM

Thanks Jim. I guess that's the approach I'll have to take. Ugh.

BlownMGB-V8 · June 02, 2018, 08:01:49 AM

Yeah I sympathize. Might want to concentrate on those two metal rings and try to break out the plastic between them. It could be phenolic in which case it should break out easily.

It is possible they assembled the pieces and then injection molded it either with phenolic (heat-set resin) or a heat melt resin. In either case disassembly probably means some degree of destruction. Or if very lucky it just might press apart.

Jim

jjohanski · June 05, 2018, 01:24:33 PM

Here are some other things I have found out through web research:
The Toyota Yaris units are fragile and subject to damage to the torque sensor. Additionally the ECU and steering column should be matched and if not may require recalibrating which cannot be done without a diagnostic plug. Recalibration of the Saturn unit is done with pot inside of the ECU. Advantage here is Saturn (aka Equinox). The Prius unit operates in fail safe without the need for a Bruno controller but may be too much assist. The amount of assist needed is subjective which gives those units that need a Bruno controller an advantage. The ability to return to center is more related to the castor angle than the steering unit. Most have found that 5 degrees is needed for good return to center and the stock MGB has about 6 degrees so should be ok no matter what unit is used. The Saturn unit is the most used and readily available along with the matching ECU. Most of the Mustang and British car guys use the Saturn unit. The Bruno automatic controller while not being speed sensitive is torque feed back sensitive which may be just as good as a speed controlled unit as the Yaris.
So now I am leaning to the Saturn unit. Off to the pick and pull to get one for testing.

BlownMGB-V8 · June 05, 2018, 02:16:35 PM

Mike's conversion of the Saturn unit is relatively straightforward. In general I would recommend that unit over the Corolla even though it is larger, because the conversion is simpler. Therefore whether you do it yourself or buy one from Mike already set up, the cost in time/money is less. The Corolla does make a neater installation as it can tuck completely up behind the dash.

The Prius unit is similar to the Corolla. Limp mode is very close to the Saturn at half scale on the Bruno knob, quite acceptable. Return to center is near identical as far as I can tell.

Jim

cgill · June 06, 2018, 01:02:11 PM

That's funny, return to centre on my Corolla EPS was much better than the Saturn unit I had.

BlownMGB-V8 · June 07, 2018, 06:43:36 PM

Well, my car and the Roadmaster are not set up identically in the front ends so your back-to-back testing should be the more accurate comparison.

Jim

jjohanski · June 09, 2018, 10:46:53 AM

TO Chris: So did you get your problems sorted out? You comment that the Toyota unit was better than the Saturn for return to center, so I presume that your Toyota unit is working fine now? Please comment.
I have a Yaris unit and a Saturn unit from the pic n pull. I am awaiting some parts in order to do a test.

jjohanski · June 15, 2018, 08:01:14 AM

I have just received the Bruno Automatic control and bench tested it on the Saturn Vue steering column that I got from the Pic and Pull. It seems to work well and does vary the output as the amount of resistance is increased. Of course this test is subjective and done on a bench with two vise grip pliers. What happens once in the car will be the real test, but that will not happen for me for a couple of months.
The Yaris unit that I got does not seem to work--I think that the torque sensor is damaged. The car that donated the unit was hit on the front end. As I said before, the Yaris unit may be the most fragile.
Next task is to build the column and install it in the car, and then do some road testing. I will report back on this when complete.
In the interim, any feedback from others is welcome.
I hope to see some EPAS units at this year's get together in Ohio.

BlownMGB-V8 · June 15, 2018, 09:39:40 AM

Should be several there. Undoubtedly Mike's car, my car, the Roadmaster, I'm pretty sure others will be there also.

One of the biggest challenges is retaining the collapsible column feature and there are several ways to do that. Time will tell what works the best.

Jim

jjohanski · June 10, 2019, 06:28:44 PM

Well a year has almost gone by and there has been no postings on the EPAS subject. Carl Floyd PM'd me and asked if I had gotten any further along--I have not as I am not yet convinced (after driving an MGB with power steering) that it is really needed. I do think that there is a lack of centering with the Saturn conversions, but not unmanageable. I definetly like the feedback on a non PS car on the highway.
I still think that the best solution is the Yaris unit with a VSS input. This unit from non ABS cars is the only unit I know of with the ability to vary the sensitivity vs the speed of the car. As I said earlier, the Yaris seems fragile as the unit I got from the Pic and Pull did not work, the car having suffered front end damage. I still would like to try a Yaris unit and use a vss from a GPS speedo. This if works would be the best with real speed sensitive variance and according to those who use Yaris (also Prius, Nissan, and other Japanese based systems) with the ability to give steering feedback and centering at all speeds. So I may just opt to obtain another Yaris unit and try it.
Any thoughts?

BlownMGB-V8 · June 11, 2019, 10:39:55 AM

I like the Toyota, I think I got more column collapse but it requires machining. Limp mode is 50% which is about right for the B with wider tires. However, without a VSS signal it takes 3 seconds to initialize. Pros and cons. With stock weight and tires is it worth it? Maybe not.

Jim

jjohanski · June 14, 2019, 05:38:14 AM

Still thinking about EPAS. Any one with experience on this?: http://www.dcemotorsport.com/Home/EPAS#Microsteer

jjohanski · June 14, 2019, 08:12:56 AM

Here is something that is also interesting: http://forums.y-blocksforever.com/Topic112422-2.aspx

BlownMGB-V8 · June 14, 2019, 09:58:27 AM

Thanks for that link. They seem to have the Yaris unit sorted out, and even have the connector body and pin numbers and sources. Not so much on the Prius unit. So as it stands now, if you are willing and able to provide a VSS signal of some sort it looks like the Yaris will do speed sensitive steering, which is a great benefit with heavier cars. It appears that MGB owners using the Bruno box are mostly setting it somewhere midrange and leaving it there. My experience with the Prius unit is that the midrange default (43mph) works well with wide tires and a bit of extra vehicle weight. YMMV.

Jim

MGBV8 · June 14, 2019, 03:03:21 PM

Quoteas I am not yet convinced (after driving an MGB with power steering) that it is really needed.

In most cases, of course not, James. It can make all the difference for some.

jjohanski · June 25, 2019, 09:34:44 AM

Carl, I agree and think that having the assist at lower speeds and the automatic speed sensitive control to reduce or cancel the assist at higher speeds is the ideal solution. This is what the current technology in the newest cars does. The requirement with the Saturn based systems to adjust (via the Bruno controller) does this but it is not automatic. The Yaris based system does this automatically but requires a pulse generator to "wake" the system up upon starting. The new DCE system seems to do this. All comments are welcome. Anyone out there have experience with the DCE Microsteer system?

BlownMGB-V8 · June 25, 2019, 10:59:28 AM

Be aware, the EPS will change the steering characteristics of the car whether it is on or off. What you have is a fairly large ring gear being driven by a worm gear on the assist motor. The worm and ring creates resistance. When unpowered that adds to the heavieness of the stock steering, and it reduces the snappy return-to-center that the OEM arrangement creates whether powered or not. Any reduction in camber or caster (particularly caster) will also reduce that effect, whereas wider tires will add to it.

So, adding EPS will reduce steering effort but also reduce return-to-center (which is a bit excessive in the stock MGB anyway). But without power it makes the steering a good bit heavier, as well as the reduction in return-to-center.

Jim

jjohanski · June 28, 2019, 06:48:11 AM

Jim, Well said and accurate!

MGBV8 · July 01, 2019, 01:10:40 PM

I found this interesting:

The Miata has Mazda's second implementation of rack-mounted electric power steering

The first application was in the RX-8, but while most modern Mazdas use electric power steering, it's really tricky to fit rack-mounted systems in front-wheel-drive cars. In the 2016 Mazda MX-5 Miata, a rack-mount assist system allowed engineers to improve steering feedback (other cars have the assist system in the column, which is less precise). Mazda did experiment with unassisted steering for the new Miata, but officials say the effort at parking speeds would have been too high.

jjohanski · July 08, 2019, 04:46:37 AM

Carl, Interesting comment. I have two modern cars--the older is a 2018 Chrysler 300 AWD with electric power steering on the rack as the Miata. The steering feel is good with a dampened return to center and almost no caster feel in the straight ahead position. This gives the car a light feel on the highway but the car does not wander. I suspect this feel is programed in. The second car is a slightly newer 2018 Ford Fusion Hybrid. This car has the has the electric power steering on the column and is virtually the same feel as the Chrysler. Again I suspect that is the programming. Both systems are speed sensitive.
This brings me to my present decision. I have decided to through some bucks at this and have purchased a DCE Microsteer system from Flaming River. The unit is in my hands and I plan this week to build some column and bracketry parts. I also hope to do some bench testing. This system goes both ways with a control much like the Bruno controller and an option for a pulse width speed input. I will be using the input from my GPS speedometer at 8000 pulses per mile. Unfortunately road testing will not be done until sometime this fall, when the progress of my V8 conversion is back on all fours. I will post information as available. As always comments are welcome.
BTW, I know that I had said that I did not think the EPAS was all that necessary, but it sure would be nice to have the low speed assist with the highway feel of the unassited MGB. Of course the highway experience will never be as "strong" as a non assisted MGB but if it is as good as either of my two modern cars, I will be quite pleased.
Comments and observations are always welcome.