Thanks for the clarification and details. I've already put in my PowerTrix pre-order, which I am still happy with, but good to document another option. Plus, if someone orders these from Japan they can use this line:

 

You ever figure out the perfect OEM+ suspension for a RWD Sport Sedan?

 

Perfect doesn't exist

But, yes, I believe the Powertrix are a great option. Mine just delivered a few weeks back. Things were delayed a bit due to the tariff/shipping challenges. I need to find the time to install them; the past month has been crazy and I haven't had time. Perhaps in the coming weeks. I'll report back once I get them installed.

 

Perfect is somewhat utopian, but I think there are multiple much better than average options using both lowering springs and coilovers.

 

Ok, I finally got around to installing these coilovers. Summer was HOT and busy. 100 degrees in the garage is too much for me to go out and wrench. I had never done a coilover install before, and I am not an expert mechanic. But I have all the tools required, including a cordless impact, and have enough mechanical understanding to follow directions. This was about as difficult as a brake job, so not too bad.

One key note: With the Powertrix setup, the sedans need a 9" rear springs. The 8" is too short and result in a minimum ~1.5" drop in ride height. But, Charles at Powertrix is awesome to work with! He quickly shipped out the 9" springs to me and I sent the 8" springs back to him.

I went with Swift springs at 12k/10k, and I can tell the springs are stiffer than stock, but I am very pleased with the ride so far. The Powertrix shocks feel well damped, in my opinion. It further confirms that my stock shocks were worn out. There is a road right by my house that the car bounced on with the stock suspension, but now it's smooth with the new Powertrix coilovers.

I am currently at about 27 1/8 fender height in the rear and about 27 1/4 in the front. This is a 5/8" drop in the rear, and 9/10" in the front from the stock specs in the FSM. I've only put about 20 miles on it, and I think the shocks and springs are still breaking in and settling as the measurements seem to be changing slightly each time I get out and measure. I am going to put a few hundred miles on it, and then figure out what adjustments to make. The good news is that I've been in and out of multiple driveways that I frequent and clear without a problem, which was my main concern with lowering the car. The stiffer springs dont use as much travel, obviously, thus while starting lower, they don't compress as much as thus avoid scraping.

I'll report back when I've put more miles on the car. So far, I highly recommend Powertrix: Charles is fantastic to work with, the coilovers seem high quality to me, they have separate preload and ride height adjustment, and the ride is firm, but well damped.

 

I have 700 miles on the car since the coilover install, and it was a beautiful sunny (and cold) winter day, so I took the car out and measured fender height. After the first measurement, I remember that when measuring sag on a dirt bike or mountain bike you always want to bounce the bike, let it settle, then measure. So, I figured that's probably good idea with the car as well. After doing this, I am getting very consistent fender height measurements. The front is at 704mm (27.71 in) and the rear at 696mm (27.4 in). I am stoked that my fender heights are consistent from side to side as that means I measured correctly when installing the coilovers.

Per the FSM, stock measurements are 715mm (28.15 in) in the front and 705mm (27.76) in the rear. So, I am 11mm (.43 in) lower in the front, and 9mm (.35 in) in the rear. I think I have accomplished my exact goal with these coilvers, namely a good OEM+ sedan coilover option with a reasonable ride and close to stock ride height. If you are looking to accomplish the same goals, make sure to go with 9" rear springs!

I am not scraping anywhere, so now I have to deciede if I want to go another 5 or 10 mm lower .

Edit: Another note - I should have measured fender heights before installing the coilovers, as tire diameters vary slightly, and thus the comparison to the FSM isn't going to be exact. I see my measurements from when I first installed showed more a drop, but that was with my summer wheels and tires. I am now on my OEM duckfeet with winter tires.

Edit 2: My winter OEM sized 225/50/18 fronts are 5mm taller than my summer 245/45/18 summer fronts, assuming the tires match their sizes exactly. In theory, that means I'll be 5mm lower in the front when I switch to my summer wheels and tires. So, I am keeping my ride height as-is.