My proposed mods
 

Having driven the car since August 2017, I've gotten a pretty good feel for it. As posted, I am now running 255/45 18 tires and am much happier. I am satisfied with the power and performance, but I think 2 things are needed.
1. a bit too much body lean. I am thinking Hotchkis front and rear sway bars.
2. Not enough brake. Given my track experience, I am inclined to do the Akebono front brake upgrade and leave the rear as is. With DOT-4 and stainless lines I think stopping power will be adequate.

I have searched these forums endlessly for tips, and think I am on the right track.

FOR GOD'S SAKE STOP ME IF I AM WRONG! :icon17: I don't want to spend a couple of thousand dollars and hate the results!

Thanks for listening.

Also, Z1 is local to me. Anyone had work done by them?

Sways and brake upgrades aren't a bad plan. I would just go ahead and get the full F&R kit though, the rear sedan rotors are puny @ 320mm vs the 350mm of the Akebonos and if you go the remanufactured route the cost for the whole kit is pretty affordable.

In opposite order...

Brakes IMHO are a good choice but pads affect braking more than calipers. The bigger calipers/rotors will reduce fade. Also be aware that the akebono/14" rotors won't fit behind many wheels, and will require different brake lines, brackets, and rotors. Maybe different master cylinder - the big 4-pots use more fluid than the base calipers. Search on the forum elsewhere, there's a re-manufacturer selling the akebonos (powedercoated red, of all things) for $300 ish for the set of 4. Not saying you shouldn't do it, but there's some parts research to be done before you're sitting at the wheel well scratching your head because the wheel won't go back on.

As far as body roll, I think you are right on. My research here and with the Z cars seems like Hotchkis are the stiffest streetable sway bars. With my prior cars, that was one of the first mods I did - racing beat sways on my RX7s and RX8 and RX8 sways on the miata. Even have upgraded the rear sway on our CX-5 which makes it turn in much sharper and more responsively (on an already nimble-for-utility-vehicle car). Looks like end links are a weak point, which is understandable considering the weight of the G37. Moog apparently has HD end links that work, or you can piece together end links with heim joints from Summit Racing or Jegs (but those will increase NVH).

I've always been a fan of stiffer bars and dampers rather than springs; let the suspension do what it is supposed to do. *some* body roll increases traction by shifting weight.

https://www.aircraftspruce.com/categ...gs_aurora.html

If it's good enough to move the ailerons on a passenger jet, it might just work OK on your swaybar :)

You might want to think about a higher temp brake pad and some updated brake fluid I use ATE type 200. You also might want to think about getting the Z1 two piece rotors, you will save 10lbs a side. I would think that the factory suspension getting pretty soft, you might want to look into some coil overs. You might want to look into the subframe collars to stiffen the back of the car. I got my stuff from Z1 I think they legit.

+1 on ATE type 200.