Did a lot of work this afternoon. I've had it all apart enough times now that it really didn't take long. (I've also had it apart enough times, and been over-torquing the lower strut bolts enough that I destroyed the threads on them and had to replace them... but, I saw it coming. I had replacements on hand when one of them finally seized today!)
So, I lowered the rear to match the front. I set it a half-inch from as low as it would go. (I like to leave a little on the table) I've got some rattles back there now, I need to go back and look and see if I can figure out why.
And then I took the front apart and stuffed my 450# springs in there while raising it up about an inch. (half inch with coilover height adjustments, the rest due to the springs being stiffer and compressing much less than the old springs) Quite proud of myself, too. I did all the math last night, so I knew that the replacement springs would compress 1.3" under the weight of the car... and another 1.3" at 1G cornering load. So, I knew exactly where I needed to be in my shock stroke. I was able to set things up perfectly the first time! And I was able to trim a custom bump stop so that it is right about a half inch from making contact at static ride height. It all fell together perfectly! There's something to be said for experience and understanding what you're doing.
Here's today's gratuitous "moar low" photo. All nice and level.
Something important that I learned today:
If you lower the car so much that the front tires rub against the fender liners, YOU'VE GOT A SERIOUS PROBLEM. I was ready to let it go, and just allow the tires to "self clearance" against the fender liners. Often this isn't a big deal. But, I wasn't going to let it go for too long without checking it. And it's a good thing I did!
There are three problem areas. One is at about 10-11 o'clock on the wheel arch. As you rub through the fender liner, you expose the metal tabs where the fender meets the bumper. Yes, I did take photos.
That little metal tab will SERIOUSLY gouge a tire. It looks like I only hit it once or twice, but it took out some nice 1/8" strips of rubber. Good thing it's a brand new tire with plenty of rubber to spare.
You could address that one pretty easily by removing the fender liner and either grinding off the offending metal, or bending it out of the way. But, that's not going to fix the other problem.
If you're hitting there, you're ALSO hitting the top of the fender well. Not the fender liner. The actual TOP of the fender well. I guess you could get medieval with a big hammer and maybe improve that situation a little. I chose not to go that route, myself.
This wasn't a sharp edge like the other one, so it didn't take chunks out of the tire. But, it's still not a good thing.
The third area of concern is a lot less critical. It actually has less to do with the car being low, and more to do with running a much larger diameter and wider tire (while also being low). This is a contact point that I'd noticed before, but it's DEFINITELY a lot worse just after one evening of driving around "super low" than it was after a year and a half of autocrossing. Curiously, it's only on the left side. The right side doesn't rub.
I'm talking about the rear edge of the fender well where the inside corner of the tire makes contact at full lock. I could probably fix this with a wheel spacer, but it's not enough of a problem to worry about.
This photo doesn't give a lot of visual reference, but the round hole is the bottom of the "frame rail". It's just the back side of the fender well toward the inside.
Looks like I ought to pull the front wheels off and get back in there with some paint on that bare metal, eh?