Power steering issue with slicks?

[ROADRACER]

Originally Posted by RedReplicant

This is what has been discussed elsewhere https://www.dcemotorsport.com/Home/EPAS

The units look very similar to what I ran in my Miata, which is a Koyo from a Saturn Vue (and other cars). The Pro Street ECU looks the same as my control unit and also has the same harness w/ rheostat to control assist.

I would be kind of curious to see what failsafe mode is like on the units we have. Normal assist or turns off completely?

Thanks. I didn't realize we were talking about a stand alone system. With the CAN-bus system in our cars I would be surprised if it would still drive and not go into some limp mode or have other serious issues.

[Icecreamtruk]

Originally Posted by RedReplicant

I would be kind of curious to see what failsafe mode is like on the units we have. Normal assist or turns off completely?

For what its worth, I run the EPS with its control module as a "standalone" on my LS swap. I just give it power and nothing else and its working at 100% strength all the time. After a year of testing the car at the track I've had many issues, but none of them are related to power steering. That thing stays strong and constant thru the whole session, regardless of loads. So the failsafe that gets triggered is probably not needed and if it could be disable I highly doubt any actual damage would happen to the unit.

Good luck on your problem, it was my problem as well until I swapped engines

[ROADRACER]

I would be kind of curious to see what failsafe mode is like on the units we have. Normal assist or turns off completely?[/QUOTE]

If you are referring to the stock 86 EPS unit, i can tell you exactly what it is like. The electric assist suddenly turns off. It does this at very high load moments, so the steering effort instantly becomes MUCH harder. Its not a good feeling, and can make it difficult to maintain a smooth line as it turns off and then back on. I am use to it now, but still hate it.

[treedodger]

I experience almost the exact same thing on my 2013 when switching to higher grip tires, in high g corners. Almost stock ride height w/ 7k/8k springs. It feels like the electric assist just stops completely during heavy trail braking or cornering.
No sign of rubbing inside the fender well.

Originally Posted by ROADRACER

I would be kind of curious to see what failsafe mode is like on the units we have. Normal assist or turns off completely?

If you are referring to the stock 86 EPS unit, i can tell you exactly what it is like. The electric assist suddenly turns off. It does this at very high load moments, so the steering effort instantly becomes MUCH harder. Its not a good feeling, and can make it difficult to maintain a smooth line as it turns off and then back on. I am use to it now, but still hate it.

[ROADRACER]

Originally Posted by treedodger

I experience almost the exact same thing on my 2013 when switching to higher grip tires, in high g corners. Almost stock ride height w/ 7k/8k springs. It feels like the electric assist just stops completely during heavy trail braking or cornering.
No sign of rubbing inside the fender well.

yea, Its a fairly common problem for track cars that are pushed. Reducing castor helps, but not a lot. It could probably be fixed with a software/firmware update, but I think it is buried so deep in the programming that it would require Subaru engineers/programmers to fix it, and I don't think they really care about our problems.
The steering issue and rear wheel hop when power sliding in the rain are the two things that bother me the most with my car. I have been unsuccessful fixing either of those issues.

[amirnew]

guessing this was not sorted for anyone,
happans to me also now after upgrading to sem-slick tyres... really scary and really not safe.
someone knows the reason? maybe givving the EPS direct power line from the battery trough a relay can solve the issue?
does someone has the equipment to measure the power to the EPS and see if there are major drops due to high current draw?
if that will be the cause than we can have "easy" fix.
did someone tried givving the EPS power directely from the battery before?

really need to fix this issue....

[RedReplicant]

I was able to lessen it by fixing some interference, but it didn't go away.

edit: Ordered a 2017+ module to test, worth a try since they are cheap

[churchx]

Originally Posted by RedReplicant

edit: Ordered a 2017+ module to test, worth a try since they are cheap

Do report here, if it will help. There are many that still track their early model twins.

[Kelse92]

Has anyone attempted to run an air duct up toward the location of the unit and get some cool air there? A friend of mine had a similar issue on a C7 Z06 and a air duct helped

[treedodger]

I think it's and overload issue, not an overheating issue, because it seems to happen as much in the beginning of track session as the end (on cool days).

The good news is I found a fix: Buy a 2022!

Originally Posted by Kelse92

Has anyone attempted to run an air duct up toward the location of the unit and get some cool air there? A friend of mine had a similar issue on a C7 Z06 and a air duct helped

[ClayMan]

Had this happen on a 2022 yesterday. Not a good feeling approaching a corner at high speeds!

[DocWalt]

Yup, keeps happening on my 2022 too. Some corners are worse than others.

[RedReplicant]

My car is still in pieces, but I want to try what Icecreamtruk is doing before I swap in the newer module I bought. It sounds like you can run it with no CAN integration, just power, and it no longer has cut out. I don't know what this means for an otherwise stock car since we are both on standalone ECUs, mine a Haltech with stock CAN integration.

It is pretty terrible to hear this is an issue in the new gen too.

[Spartan117]

Dont mean to revive a dead thread, but its pretty obvious on the new gen as well and I'm hoping to ID a fix.

So while I don't have a fix. I'm able to replicate every time give exception to cool down laps.

It only happens to me while I'm entering a turn where the track is graded downhill [so the majority of the weight of the car is on the front-end] while I'm trailbraking.

It happens while I'm turning both right or left and I'm not turning the wheel past 9/3 o'clock [validated by video] and it only happens on the downhillish turns between 70-80mph [via video/gps].

Running a 2022brz, hats/RLCA -2.8/2 camber on 17" rt660s.