I'm already excited about the prospect of new alloys that will shave
seven pounds off the corners, or a pound or two less depending on the
plus sizing factor.

Now I'm seeking advice about diminishing marginal returns as regards
more rubber on the road versus further reducing unsprung weight.

My '05 Accord LX 4Cyl 5M came with Michelin's "CAFE" tires, good for
fuel economy but not much else, scoring in the bottom half of most
everything in Performance All-Season category. But they are already
fairly light for 205/65 HR15 92H tires, at 21 pounds each.

My challenge is to find the best weight to performace ratio for the
tire. Less unsprung weight means the suspension works better at what
it does, including keeping that tire on the pavement where it can do
some good.

Goodyear TripleTreds score very high marks for ride and noise comfort,
but do they score so well _because_ they're 5# heavier per tire? I
probably wouldn't pay that price if I could have a pretty good ride in
a less beefy tire.

It's easy enough to improve the wet and dry traction with better
compounds. Improving handling and steering response can be done by
brand selection, but sometimes it means reducing the aspect ratio.

One challenge I face is figuring out how much of (handling/ride) to buy
just by switching tire makers at the same size. Some tire makers score
dramatically better than others in Tire Rack's ratings, such that just
by switching makers, you gain improvements in both areas at the same
time. (But switching to the top rated Turanza tire in the same
category adds four pounds!)

Then again it's possible to make improvements in one area by trading
off against another. The examples below adjust unsprung weight changes
for plus sizing.

With example (2) below (Kumho ECSTA HP4 716s), I can get 8/10" more
rubber at the OE TIRE weight, while cutting the sidewall by 6/10".

Matching the stock tire exactly with option (1) would mean giving back
two pounds in exchange for across the board preformance by changing
brands.

With option (3) you drop one more NET pound, putting you eight pounds
lighter overall

22# Steelies + 21# OE Tire = 43# W+Tire

------------------->S+W/DIFF/Sect Width
1) 205/65 HR15 92H---38--5---8.1"
2) 215/55 HR16 91H---36--7---8.9"
3) 205/55 HR16 89H---35--8---8.4"
4) 205/60 HR16 91H---36--7---8.2"

(16x7 alloys are a pound heavier than 15x7)

If they all satisfied your +/- 3% speedo, and the speed rating was OK
and the load rating didn't matter, which would you pick for:

Steering response / Handling / Turn-in?
Ride comfort?
Throttle response / acceleration?
Fuel economy?

Seems to me that the 19#/8.4" section width might be the sweet spot --
but that depends on the diminishing returns theory of rubber on the
road vs unsprung weight! (The 65/60/55 differences are probably mild
enough to be inoffensive.)

Thanks for your thoughts on this.

-- CL.

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