Steering issue under braking !

[AJ PwR]

I have been noticing this issue for quite a long while. Whenever I try to trail braking into a turn, the steering felt like it is locking up and I need a lot of force to crank the steering before I can turn. The incident gets more worse when the car goes down hill. So in order to avoid it, after I brake, I have to get on the throttle quick and then the steering will not lock up.


Does anyone here experiencing the same issue ?

[BRZZZZZZZZZZ]

This has happened to me once or twice at auto x.

[glamcem]

Originally Posted by AJ PwR

I have been noticing this issue for quite a long while. Whenever I try to trail braking into a turn, the steering felt like it is locking up and I need a lot of force to crank the steering before I can turn. The incident gets more worse when the car goes down hill. So in order to avoid it, after I brake, I have to get on the throttle quick and then the steering will not lock up.


Does anyone here experiencing the same issue ?

You might be rubbing the tires hard like I did at ORP one time..
Have you ever checked your inner fender well? Tire and wheel size? and more importantly how much is your car lowered? are you the owner of that white BRZ with the wing? if you are I remember hearing a lot of tire rubbing at your RMP video so that might be your issue



I set my damper settings to the 2 click (from the stiffest) and raised my car about half an inch ( used to be 1.5" drop now it's about 1" all around), it solved the issue (it used to be 6-7 click from the stiffest) and having +35mm offset also helped I think..

[wparsons]

Does the same thing happen if you enter the corner slower, but under the same braking force? If the front end is pushing it can really stiffen up steering effort.

[Kimsey47]

http://www.ft86club.com/forums/showt...t=Peddle+dance

I think this may be up your alley...

[BRZZZZZZZZZZ]

Originally Posted by Kimsey47

http://www.ft86club.com/forums/showt...t=Peddle+dance

I think this may be up your alley...

Ive had it happen with both just traction control off, and doing the pedal dance.

[CSG Mike]

Originally Posted by AJ PwR

I have been noticing this issue for quite a long while. Whenever I try to trail braking into a turn, the steering felt like it is locking up and I need a lot of force to crank the steering before I can turn. The incident gets more worse when the car goes down hill. So in order to avoid it, after I brake, I have to get on the throttle quick and then the steering will not lock up.


Does anyone here experiencing the same issue ?

You can muscle past it, but you can fix it by correcting your suspension geometry in the front.

Will Rob be driving your car at SLB this year?

[AJ PwR]

Thanks everyone !

Couple years back, I had this issue already and I thought my car was too low. My car had about 1.5" drop and was running 235/40/18. It was hitting against the frame above the tire so I raised it about 0.5, lesser problems

This year I was running 265/35/18 problem still there and the recent track days I am running 245/35/18 (I have more wheel gap) , I have about 5 inches clearance between the tire and frame. I need to get on the accelerator sooner so when the weight transfers to the back, the problem goes away but this is not cool that I couldn't trail brake.

I did the pedal dancing so TRACTION is OFF at all times.

Here's what I am running at the front !
- RCA
- coil-overs with 8k springs
- front sway
- all bushings replaced
- roll center tie rods

You can muscle past it, but you can fix it by correcting your suspension geometry in the front.

Will Rob be driving your car at SLB this year?

I have not decide to come or not but if I do Rob will be driving !

[Kimsey47]

Originally Posted by BRZZZZZZZZZZ

Ive had it happen with both just traction control off, and doing the pedal dance.

Worth a shot since I didn't see it mentioned previously!

[Element Tuning]

Yeah I've had that problem since day one on slicks. The electric power steering is overheating and it basically turns off your steering assist momentarily (or the entire corner).

[dradernh]

Originally Posted by Element Tuning

Yeah I've had that problem since day one on slicks. The electric power steering is overheating and it basically turns off your steering assist momentarily (or the entire corner).

What do you think will minimize or eliminate this?

[Element Tuning]

Originally Posted by dradernh

What do you think will minimize or eliminate this?

I've started to build a liquid cooler for the steering motor but in have yet to install or test it. I got really sidetracked with making the motor relaible at high power. Since I've been able to drive through it I've just dealt with it.

Certain tracks it's worse than others and it's trail braking after a long sweeper that does it for me.

We may do something with the Hydra EMS if the cooler doesn't work that would allow us to tune the power steering to reduce the normal force which should in turn hopefully keep it from overheating so easily.

Thanks,
Phil Grabow

[dradernh]

Originally Posted by Element Tuning

I've started to build a liquid cooler for the steering motor but in have yet to install or test it. I got really sidetracked with making the motor relaible at high power. Since I've been able to drive through it I've just dealt with it.

Certain tracks it's worse than others and it's trail braking after a long sweeper that does it for me.

We may do something with the Hydra EMS if the cooler doesn't work that would allow us to tune the power steering to reduce the normal force which should in turn hopefully keep it from overheating so easily.

Thanks,
Phil Grabow

Good to know. Thanks.

I'll be at the Glen next week in a student's FR-S and will keep an eye out for it when we trail in to T6.

[CSG Mike]

Originally Posted by Element Tuning

Yeah I've had that problem since day one on slicks. The electric power steering is overheating and it basically turns off your steering assist momentarily (or the entire corner).

This doesn't make sense to me; I've driven cars without power steering, and it doesn't have this type of effect.

I've noticed that front geometry has a large impact on how this phenomenon kicks in...

How were you able to determine that it's the electric power steering momentarily deactivating? It's not something we've ever logged or even put a sensor on, since we eliminated the issue on our cars.