It took me much experimentation and a thorough understanding of what happens with the rear suspension in the gen 7 Accord, before I got a setup that provides stable, solid handling and little to no tire wear issues.
I bought the car with dealer installed HFP suspension, which is dropped about and inch or a little more than a stock 6 speed coupe. This caused excessive negative camber and toe-out in the rear suspension.
The toe-out is a result of the designed in passive "rear steer" built into the suspension as it's compressed.
Look at it this way, if you're making a hard right turn, the car leans towards the left, the left rear is compressed, it goes negative camber from compression, and the way the links and bushing move add toe out. The right rear, goes positive camber and toes in. This effect, causes the rear of the car to "steer" the rear of the car towards the outside of the turn. This effect isn't really noticeable in a stock suspended Accord.
With the lowering, then my addition of the TL-S 27.2 hollow front bar, and the 20mm rear bar, while leaving the alignment alone was a huge mistake on my part.
Now, with the larger sway bars, Honda's usual design of heavy understeer is being reduced. Add the screwed up rear alignment.... and it's a problem waiting to happen.
I found out the hard way, as a large truck blew a tire in front of me, I swerved to avoid a large chunk heading for my face, and the car made the initial lane change. Unfortunately it also began to oversteer (fish tail) as I got into the left lane, I tried to correct and it violently snapped hard and spun. 6 times I went around, looking at oncoming traffic at the speed I was doing (75) until it slowed enough to head towards the ditch and trees. Luckily I was able to stop the car.
The messed up rear alignment was only allowing a small amount of the rear tires to actually contact the road and the steady state toe out causes a destabilizing effect.
I put a set of better summer tires on, dumping the OEM gripless Michelins and then had the whole car aligned, having the front subframe shifted to get camber where it was acceptable.
With a half tank of fuel:
0 degrees R, .025+ degrees L, caster to wherever it was, toe in front to dead zero. You could toe it in a tiny bit for more stable on center steering, a little toe out if you like better turn in, at the sacrifice of nibble. The rear end I had set camber at -.9, the most positive preferred factory setting, and toe at 3mm total toe IN. Toe in on the rear will improve stability. (my car started at 3 degrees negative camber on one side and almost 4 degrees on the other, with 4 to 5 mm of toe out) Tire pressure on my particular summer tires: 37F 32R
Since then, the car is dead solid stable, the car doesn't exhibit busy or nibbly steering, and if I really push it, it will 4 wheel drift. (in the dry). On very sharp, slower speed corners, I can actually feel the passive rear steer work, you turn, and the car just goes, with a hint of movement where you unwind the steering while still in the turn and put the power on and go. The car will understeer in low traction, wet, dirty or snow as you just can't avoid the forward weight bias.
I've got about 40k on my summer tires, and about 20k on the winters. The summers only show slight inside wear, but is offset by the cornering wear on the outside of the tires. For reference the stock Michelins only lasted 20k before being bald on the inside 4 ribs of the rear tires.
My winter tires, I run them at 34F 32R, they have much stiffer sidewalls than my summers, any higher and I get beat up. Using these in the snow since the alignment changes, the car seems like a mountain goat. I have traction, stability and confidence inspiring feel. Of course I keep the speeds sane, as to not have issues with ice, etc.
You really can't stiffen the chassis too much as a platform for proper suspension tuning, but you can the suspension, too stiff, and it won't be able to conform to larger irregularities and hop around and be disturbed too much.
