Steering doesn't return to center and car pulls to the right
 

Car had RCE Yellow springs all around with stock shocks, Ingalls camber bolts and rear SPC LCAs. Just added Bilstein B6 shocks/struts along with Raceseng CasCam plates and swapped the SPCs for SPL rear LCAs. I'm on Enkei RPF1s, 17X9 +35 shod with Hankook R-S3 V2s with all 4 corners at 35PSI.

I did drive about 5 miles to the alignment shop on the before settings. After leaving, car doesn't pull in either direction at street speeds but she pulls pretty strong to the right at highway speeds. At street speeds if I U-turn, for example, and let go of the steering wheel the car will continue steering, steering wheel never returns to center.

I think my alignment's good, where should I look now?

https://i.imgur.com/AjgbM3V.jpg

Unless the car is bent up I have no idea why it would be that bad.

Take it back to the alignment shop and tell them what it's doing and have them throw it back on the rack and inspect the car. It's possible they left something loose like a camber plate or toe arm which could cause what you're feeling.

Alignment looks good, you wrote that pressures are checked/even. I recall one case of pulling to one side under power due problems with diff, where mostly just one wheel provided thrust, but probability of that to happen is low. Imho most probable something what strat61caster mentioned, even more so because it's after alignment shop visit.

Are the front springs held captive at full droop with this setup?

Car was straight before the install :/. Do you know what would cause the steering not to return to center, is it caster? Unfortunately I just put the car in storage as I have some more pressing things to take care of but I did check the obvious bolts and everything seemed tight, but I'll double check in a month or two when I can get the car back. Thanks again for the reply.

Could be a bunch of things. First thing I'd do is see if it's worse under throttle or under braking, that'll tell you if it's the front or rear axle.

Put the car on jack stands. Shake every arm in all directions and see if you can find something loose at the suspected end of the car. Spin each wheel, with the brakes released and the car in neutral they should spin with little to no resistance. If you have resistance at any corner, take the wheel off. Look for uneven brake pad wear. Have someone hit and release the brakes a couple times and makes sure it's not sticking. If that all checks out, take the brakes off and spin the hub again. Any noise at all indicates a failing wheel bearing.

If you don't find anything, you missed something. There's nothing in the steering rack that magically returns the wheel to center, it's a function of the suspension design. So it's in there somewhere.

Caster does influence self centering behavior rather noticeably but your numbers are good and close to stock so you'll need to put it back on the rack to inspect to ensure your alignment is still what you think it is.

And for caster to get from 6 to 0-1 degrees to almost not return wheel back .. there should be something really bad happened that hardly can pass unnoticed, like crash bending suspension bits and so on.
If car is rised for inspection i'd also check anything that moves when you turn wheel lock to lock, if something isn't overtightened/bushings shot/whatever, that may make it to "stick".