hardtailer

Agree but putting it at # 1. of 3 possibilities is considerably different from 'not ruling anything out'.

GC996

Read what I wrote again. Just a list of possibilities to review bud. Unless we review the components in question and drive the car, tough to know.

Emefef

Last year I noticed that the ABS tended to come on at really low speeds, in the front. Michelins only had 1000 km on them. With more experience, I realized it was happening on rough pavement.
Another issue was the rear end "wallowing" in some situations - most often accelerating through a gradual uphill curve (like an entry ramp). I didn't do anything about either, planning on first addressing the significant bore scoring...
When I had the engine done, I got new engine mounts. Some of that wallowing was addressed. Then I did the shocks all around and both issues were gone. I'm replacing other suspensions bits gradually, but the new shocks made the biggest difference.

I like the motorcycle analogy - whenever I felt twitchiness under hard braking, I would first blame the mechanic before questioning my technique. No matter what, it always seemed to be my own fault...

GC996

Good info. Especially on the motor mounts. I am replacing mine in 2 weeks. Curious as to how the overall dynamics change since I am running the original mounts (57k) Then I will do the same with the transmission mount at a later date. Curious on any changes to car dynamics that each component has on the street and track. Hence staggering the replacements.

hatchetf15

OP - Welcome! First suspect is always tires. Only contact patch with the ground. What’s their story? Brand, type, pressure you’re running, age, etc. If it brakes straight and is controllable, I’d start there. Might want to take it to Protech if you get stumped. They rebuilt my engine years ago.

Mike Murphy

There’s probably nothing wrong with your suspension or shocks or anything. Your car is acting normally. HARD braking should be done in a straight line. And your suspension and shocks have nothing to do with that after initial bite, and before brake release. Unless the road is uneven. If you try to turn the wheel at all during super hard braking, the rear end is going to feel like it’s on ice, so that’s why people trail brake in slow corners at slower speeds in this car, and not hard braking at high speed.

Yes, alignment, tire pressure have more to do with this than the suspension.

The 911 floaty feeling is what gives you pinpoint control over where you want the car to go next in a turn.

Btw, the front end of your car could also feel floaty under WOT in anything other than a straight line. Some people come and post about this, and yes, alignment and tire pressures are mostly the issue, but the road is next, especially elevation changes combined with turning at high speed.

Nate.Evans

They're the one doing the alignment on the 7th...kinda just bracing myself for the worst case scenario.

Yeah, I've driven a few before, but this is just the first that's mine. The hard braking is definitely done in a straight line, being done before approaching the corner and it just feels really vague and the rear end feels wallowy....kinda hard to explain. Conversely, I hop in the Macan turbo and jam on the brakes and it feels PLANTED. I'm hoping this is is just an alignmen thing.....

I'm probably going to replace those here before the alignment just because...simple enough job...then when my IMS solution gets installed on the 14th, have them replace the transmission mount.

Emefef

You didn't tell us whether you waited for the snow to clear before these tests...or did you do them on the slippery concrete in the underground parking garage?

Nate.Evans

😂 there’s no snow on the ground.

Dr_Strangelove

I always think of this video. Bushings are still on my list because of it.

Mike Murphy

Sounds like something is broken then, as you seem to know this stuff better than most. You’re onto the right clues: alignment, shocks, tires, etc.

hatchetf15

OP - What shoes are on your car? What model, dates, depths and pressures at all 4 corners? What you describe could mostly be tires and/or pressures. This question just to help rule them out as a primary. For example, if your rears are set at drifting pressures, then guess what. Things like that.

Nate.Evans

All 4 tires are brand new Sumitomo Z5s, 50psi all around per Sumitomo’s tire chart. Tire dates show all 4 tires are all less than 9 months old.

Fishah

Porsche PSI recommendations are more important than Sumitomos.

I don't believe it's causing your issue, but man 50psi square is not ideal.

GC996

Don't know the tires, but thats a lot of tire pressure.