Sloppy, wild steering after BMR K Member install

[turbosc297]

Hey everyone,
My '22 GT feels like it's going to steer itself out of the lane on the highway or over bumps.

Here's the backstory- Just finished up installation of the BMR street K member. Also did motor mounts, camber plates, and headers at the same time. Car is lowered an inch on steeda springs and pro-action shocks/struts. IRS has solid bushings, toe links, vertical links, and solid diff bushings.

So after the car is back together, the alignment is wayyy out of whack as I expected it would be. I performed a garage alignment with final specs of 2-2.5deg neg camber (this is the closest I can get to my desired 1-1.5 deg without camber bolts) and .2 deg total toe in. Problem is the car is darty, it tramlines like crazy, and over bumps or any suspension swings it wants to change direction without warning. Same wheels and tires as before- velgen vf5 with 265/35 front and 295/35 rear Kumho Ecsta PS91.

So far I've tried the following with no luck-
-Checked steering shaft connection for play
-Checked end links and all control arm connections for play
-Checked Kmember mounting points for tightness
-Double checked alignment specs
-Checked steering rack mounting bolts for tightness
-Check strut and camber plate mounting points for tightness.

Also, I used the upper hole on the K member for the control arm since the car is dropped 1.25". Could that be my issue? It's probably the only thing I haven't played with yet.

Any suggestions to me from becoming a mustang in the ditch statistic? TIA

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[compprep]

Did BMR tell you to use the upper hole due to the 1.25 drop? I looked at their installation instructions and they don't mention either way. I had this installed a few days ago, waiting for supercharger to be done, so no idea how car will be for awhile. I'm dropped 1/2" so used the lower hole as it's closest to stock.

 

[Grimreaper]

How'd you set your toe? String or plates?

 

[galaxy]

.2° toe in is A LOT. As in way too much. Total toe should be in the .06° or less realm.

 

[Mike Pfeifer]

Sounds like a toe problem to me. Check your specs and measurements.

 

[turbosc297]

Thanks guys. I used string and measured from the outermost tread groove at the highest point possible under the chassis. Raise the car, adjust, and then lower the car and roll back and forth to relieve bushing stress, rinse and repeat until I got to .2

I'll try readjusting closer to neutral from .2 degrees and see what that does.

BMR wasnt clear on which hole to use so i picked one being that i was lowered. If the toe readjustment doesn't work I'll go to the lower mounting points on the kmember And see what that does.

 

[WD Pro]

BMR wasnt clear on which hole to use so i picked one

Don't blame you, sometimes you just have to take advantage of vague instructions ...

Who's BMR ? Is she nice ? Got any pictures ... ?

WD

 

[RagmopInKona]

Get it in a Alignment rack, and start with getting the setting in spec, and while on rack, push on the core support with hood open and see what it does aka bump steer.

 

[kz]

Set front toe to zero and see if that helps.

 

[turbosc297]

What am I looking for when checking bump steer? Change in toe or camber or both when the suspension is compressed?

How many of these cars need a bump steer kit when lowered? I had a 2016 with the same springs with no issues.

First step will be next week (MN weather permitting) to get the toe corrected

 

[Hotpart.com]

Sounds like a bump steer problem from raising the inner pivot points on the control arms.

 

[TeeLew]

Don't blame you, sometimes you just have to take advantage of vague instructions ...

Who's BMR ? Is she nice ? Got any pictures ... ?

WD

I REALLY want to take this the next step. I've got a good add-on. I'm just pretty sure I'd get in trouble.

 

[turbosc297]

Thanks for all the input. I zeroed out the toe as best I could and that helped ALOT. I think the long term fix will be going back to the stock mounting points on the kmember tho

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