If you only lowered it to European specs height, why do you need a bump steer kit?

The Cap'n

Are both front and rear tires new? Different tires front and rear can cause very erratic symptoms.
I agree with the Cap'n but doubt your washers would cause the symptoms you're talking about.

When you went back to the shop that did the corner balance and alignment what did they say?? Hopefully you went to a shop that is very experienced with the 911 suspension.

Also, one of the best bits of advice I picked up on this forum is to not set the tire pressure per the door jam spec of 29/36. I have the same setup as you described and I run 34/36 and the handling is much better.

Good luck!:)

Agree with the others that a touch (1/32") of rear toe in could help settle the rear of the car. New tires may need a couple hundred miles to wear in. Which brand tires?

Nice lookng ride. Prussian Blue is the best blue, but I'm biased. You cars looks very much like mine all the way down to the euro tail lamps. -J

+1, bascially more toe in rear vs front. Mine is set zero front and 1/32 each side rear 90MPH+ no issues, but I do have a tail front lip that also helps.

I had the same experience right after I lowered mine below euro height where the car feels like it literally floats or similar to hydroplaning to the other lane until I had the alignment set correctly. Runs tight now even without corner balance.

FWIW my car handles way better now that I removed the sway bars. Rear sway bar bushings were shot and that might have something to do with it, but feels much more stable now. Doesn't want to swap ends in the tire-warming swerve test.

Okay, some progress. I measured the front toe this morning and guess what? Toed out 1/4 inch reset to 1/8" toe in much better but still not right. I'll have to go to another shop for alignment check because the other corners could be off.
Thanks for all your suggestions.

This when I had my 85 Carrera was a huge help. If your running the factory rubber front spoiler without a tali, at high sppeds thhe car is not very stable(at least from my experience). best would be to remove the front rubber spoiler or add a tail.

You have your toe in setting backwards, zero toe in front, 1/16" toe in rear.

Lots of info on the web on rear toe independent suspension settings

Yet another "you need toe in in the rear" opinion to add to the bunch ...