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-   -   Steering Issue at Watkins Glen (https://www.ft86club.com/forums/showthread.php?t=130500)

milhouse 09-26-2018 01:32 PM

Steering Issue at Watkins Glen
 
I just got back from Watkins Glen where I had a relatively successful track weekend. I had an issue that I was wondering if anyone else has had, and if so, knows whether a fix is required.


When turning hard on the Outer Loop on the first day, my steering wheel felt "notchy" at one point through the turn. I could certainly steer through it, but I could definitely feel a stop during the turn, such that I had to add additional steering input to get through. At first it was light, and not a huge issue, but as the weekend progressed, the notch became harder to steer through and by the middle of day two I had to add a ton of input, such that when it released the car got completely unbalanced. The weird thing is that it only happened on that turn, and in pretty much the same spot every time.



We removed the wheels and didn't see anything wrong with the stock bushings, tie rods or control arms, and when driving normally (and even on other turns), the issue doesn't happen. In addition, I don't feel anything when the car isn't moving and I turn the wheel.


Anyone have any thoughts? My local shop said its actually normal as the car is driven harder, so I wanted to check here and see if anyone else had the issue and if they were able to resolve it.


Thanks.

tony_r 09-26-2018 01:35 PM

Probably electronic power steering cut. It happens with higher loads on turn in to mid corner. I've only felt it once, and only at the track but I know of others who feel it a lot more.

Stang70Fastback 09-26-2018 02:05 PM

Yeah, I agree that it sounds like power steering cut-out. Especially if it's happening in the same spot. I've had it happen to me on certain autocross courses - always at the exact same spot. Usually a very tight, higher-speed turn, and often where the curve of the road surface causes additional load. There's some sort of load limiter that prevents the electric motor from overheating, and it seems that those combinations can overpower the motor enough for it to very briefly give up to "protect itself." I heard that the refreshed vehicles (2017+) received some adjustments to the power steering programming to resolve that issue.

Either way, it's really annoying and distracting when it happens. You should also be seeing a flashing light on the dash when it occurs, IIRC, albeit only briefly.

Takumi788 09-26-2018 03:14 PM

Yep happens to me while entering turn 7 at the glen. There is a lot of compression making the electric motor work harder than it wants to.

Icecreamtruk 09-26-2018 04:06 PM

Are you guys sure it isnt just the tire hitting the upper part of the fender inside? Have you checked the plastic there to see if there are marks?

tony_r 09-26-2018 04:19 PM

Plastic splash guard is not strong enough to make the steering feel like it does when EPS cuts. Even still there are no witness marks on my car.

There are differences with some cars in terms of caster and end links as well. Running a lot of caster and having endlinks that are less than optimal make this worse.

kch 09-26-2018 04:39 PM

Quote:

Originally Posted by Takumi788 (Post 3137757)
Yep happens to me while entering turn 7 at the glen. There is a lot of compression making the electric motor work harder than it wants to.

Must be a T7 thing, as it also happened at T7 at Texas World Speedway (rip)

Fish Eagle 09-26-2018 05:37 PM

I have that often. Doesn't worry me any more.

I run 255/40R17 Bridgestone RE11S semi slicks, and it mostly happens with hard trail braking into slower, tighter corners.

Pretend you're a truck driver, and just muscle it. :)

milhouse 09-26-2018 05:51 PM

Thanks, everyone. While its not ideal, at least it won't cost me anything to fix...

Molez93 09-26-2018 09:15 PM

Clearly I wasn't pushing hard enough as the outer loop for me at the same event didn't produce any weird steering. ;-) ...or in any turn for that matter.

Joesurf79 09-26-2018 09:22 PM

Quote:

Originally Posted by kch (Post 3137799)
Must be a T7 thing, as it also happened at T7 at Texas World Speedway (rip)

TWS turn 7 might be the single greatest turn I've ever driven.

It's been bulldozed :cry:

Pat 09-27-2018 01:07 AM

Yeah, this is a common issue. I think the sticker the tire the more of an issue it becomes. There are probably other factors at play, too.

Icecreamtruk 09-27-2018 08:56 AM

Quote:

Originally Posted by tony_r (Post 3137786)
Plastic splash guard is not strong enough to make the steering feel like it does when EPS cuts. Even still there are no witness marks on my car.

There are differences with some cars in terms of caster and end links as well. Running a lot of caster and having endlinks that are less than optimal make this worse.

Well, I though it was the EPS cutting out for me, until I realised that all the plastic from the fender was gone and it was in fact contacting the strut tower from below (metal). It had already taken all of the paint out and had a nice polish surface on it already :bonk:

Pat 09-27-2018 10:26 AM

How wide are your tires? What is your wheel offset?

Takumi788 09-27-2018 11:23 AM

Quote:

Originally Posted by Icecreamtruk (Post 3138082)
Well, I though it was the EPS cutting out for me, until I realised that all the plastic from the fender was gone and it was in fact contacting the strut tower from below (metal). It had already taken all of the paint out and had a nice polish surface on it already :bonk:

Does it happen to look like this? lol. Just found this after a day at NYST.

I am almost still certain that its your EPS cutting out bc that has been a known issue. But the fact that our tires are hitting the chassis can't be good either.

https://i.imgur.com/t58HL0M.jpg

lutfy 09-27-2018 11:25 AM

Quote:

Originally Posted by Takumi788 (Post 3137757)
Yep happens to me while entering turn 7 at the glen. There is a lot of compression making the electric motor work harder than it wants to.

OMG DejaVu. Same here, Glen T7. First time it scared the s*** out of me but then I got used to it after realize its a common problem.

This was with R888R 255/40/17 however since then I have moved to R7 225/40 and been tracking at different locations and no issues. Unsure if its a Glen thing or a big wider taller tire thing or both.

Lutfy

Icecreamtruk 09-27-2018 11:41 AM

Quote:

Originally Posted by Takumi788 (Post 3138136)
Does it happen to look like this? lol. Just found this after a day at NYST.

I am almost still certain that its your EPS cutting out bc that has been a known issue. But the fact that our tires are hitting the chassis can't be good either.

https://i.imgur.com/t58HL0M.jpg

Looks exactly like that. Its not the EPS cutting out. Raise the car about an inch for a test, go at it and watch it not cut or feel different from anywhere on track.

@lutfy 255/40 has a lot more sidewall than 225/40. Specially since the R888R has so much tread (9/32). Pretty sure your issue was this same thing.

Edit: grammar correction.

Takumi788 09-27-2018 11:54 AM

Quote:

Originally Posted by Icecreamtruk (Post 3138152)
Looks exactly like that. Its not the EPS cutting out. Raise the car about an inch for a test, go at it and watch it not cut or feel different from anywhere on track.

@lutfy 255/40 has a lot more sidewall than 225/40. Specially since the R888R has so much thread (9/32). Pretty sure your issue was this same thing.

The fender rubbing just started this year bc I lowered the ride height. I had the same size tires on last year with plenty of clearance and the steering issue happened then as well.

Ur issue could be the fender, it may not but just know the EPS cutting is also a known issue.

Sent from my SM-G965U using Tapatalk

lutfy 09-27-2018 01:31 PM

Quote:

Originally Posted by Icecreamtruk (Post 3138152)
Looks exactly like that. Its not the EPS cutting out. Raise the car about an inch for a test, go at it and watch it not cut or feel different from anywhere on track.

@lutfy 255/40 has a lot more sidewall than 225/40. Specially since the R888R has so much thread (9/32). Pretty sure your issue was this same thing.

:bow::bow::bow::bow:

Did not think it was related but YES YES YES my fenders were rubbed pretty badly and we had to raise it 1/2 inch. This all makes sense now.

Cheers guys.

Lutfy

strat61caster 09-27-2018 02:16 PM

Quote:

Originally Posted by Icecreamtruk (Post 3138152)
Specially since the R888R has so much thread (9/32).

It's tread, not thread.

idk why this has been popping up more and more recently but it bothers me.


https://www.tirerack.com/images/tire...nstruction.jpg


https://www.tirerack.com/tires/tiret...e.jsp?techid=9

7c8 09-27-2018 04:38 PM

This has happened to me before. In my case, I can see a mark on the inner wall of the wheel well where the back of my end link was hitting it under high compression sweeping turns.


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