s2000zr

Can I get max handling performance and still have the tires wear evenly? What camber should I ask for?

ZDan

For me, -1.25 degree front and -2 degree rear camber is totally streetable. You will get slightly asymmetric wear the further you go beyond -1.5, but even at 2 degrees my rears wear remarkably evenly. I'm at ~18k miles on my RS-3s, and the insides tread depth is just under 4/32, outside at ~5/32 remaining.

As long as you're running minimal toe, you'll get reasonably long life. I don't worry about a few 32nds asymmetric "camber wear" near end of life. I would estimate that running -2degrees camber is going to cost you ~10-15% in terms of tire life vs. -.5 degrees, but you get greater ultimate lateral grip. In contrast, if you run 0.67degrees toe-in (UK "recommended"), that cuts rear tire life in half.

If you want maximum handling on stock suspension, you'll just want them to dial in as much camber as you can get, front and rear. That should put you at -1.25 +/- front and -2.25 +/- rear, depending (every car is different).

SpitfireS

Well... to start with the most important stuff:

Today I found my rear toe-in was L-0[sup]0[/sup]15' - R-0[sup]0[/sup]08'
Not really UK-spec after all.
The settings were no real reason to change as the car was driving fine, but it was on the rack so we decided to get them equal and when the tech guy was finished the rear toe-in was 0[sup]0[/sup]09' for both.

The rest of the alignment was - and still is - UK-spec,
Front 0 toe-in, -1[sup]0[/sup]10' camber and around 6[sup]0[/sup] caster - the best out of the chassis.
(I think it could be optimised by shifting the front subframe but that's way to much hassle right now)
Rear 0[sup]0[/sup]09 toe-in, -2[sup]0[/sup]1' camber.

So....

That's why the car handled and handles pretty good I guess.
The spirited test drive confirmed it 100%

Btw.. apart from the rear toe-in fault - yes, I agree - UK spec is ok for daily driving.
That said: according to ZDan rear toe-in is killing performance much more than less camber, front or rear, correct?
Maybe we should call it UK-spec v2 from now on?
With reduced rear toe-in, without a doubt.

Also, the sweet spot on the alignment computer was 0[sup]0[/sup]20', with a minimum of 0[sup]0[/sup]10 and max of 0[sup]0[/sup]30.
Why didn't Honda spec the toe-in in degrees?
Or a clear, beyond reasonalbe doubt, way to convert mm to degrees.


Btw.. there are some toes I would not like to get rid of: the camel kind
DO NOT search for images of anything related to "toe" at work, if you know what I mean.

Gernby

After talking to one of the local S2000 guys, who is also a professional mechanic, I now think the reason for my rapid front tire wear is related to caster instead of toe. Since I do a lot of driving on surface streets (coarse concrete) with tight 90 degree turns AND have a J-swing driveway (also coarse concrete), I do a LOT of turning where my tires are grinding away that inner shoulder. It may be mostly due to my driveway, where I have to do lock-to-lock turns to get into the garage.

ZDan

ah-HA! I am *vindicated*! (sort of)

So, 15' + 8' = 23' = 0.38 degrees total. More than I like to run, but for sure WAY better than 0.67 degrees!

18' total, 0.3 degrees total, I approve (not that that's required!)

Sorry, I just *have* to convert to degrees to have an idea what it is, not used to dealing with arcminutes!
-1.17 degrees front camber
-2.02 degrees rear camber

OK!

Those settings look GREAT to me for spirited street usage, sometime track usage!

For a one-off lap or autoX run, a lot of toe-in might not impact times all that much, probably less than having zero camber vs., say, -1.5 camber. But over time, though, it puts more heat needlessly into the tires (not as big a deal in autoX maybe, but can overheat rears relative to fronts at the track), wears the tires out SIGNIFICANTLY faster (when this caught me by surprise at Mosport, myself and my co-drover were simply dumbfounded at how awful the car became as the rear tires destroyed each other), and gives the car very spooky/weird/non-linear handling characteristics, particularly over irregular pavement or in traction-challenged conditions.

At the track, I would bet that too much rear toe might be a couple/few tenths slower over an optimal-conditions flying-lap, but over a number of laps, I bet it would be a lot slower. I did time-trial (three laps) OK enough running 0.64 degrees total. But the more laps I put in, the worse the handling got.

Yeah, I'm totally on board with the rest of the UK spec. -1 front camber, -2 rear camber, zero front toe, ~0.2-0.3 degrees (6' - 9' per side) rear toe would be my general recommendation for a street/sometime-tracked stockish S2000.

So the alignment computer was showing a rear toe sweet spot of 0.33 degrees, +/-0.17 degrees, that's TOTAL, right, not per side (I hope)?
I think that the high end of that range, 0.50 degrees (hopefully total!), is a bit high still...


HA! Time to do search on "best toe"...

ZDan

Never been a fan of big caster, either! Due to other suspension mods on the Z, I wound up at 3.5degrees caster. LOVED it. I usually don't worry too much about caster and have alignments done to give me the most camber I can get, but definitely prefer it in the 5.0-5.5 degree range over 6.5+. I know a lot of people insist on running the max, but IMO it's overrated (for track work at least).

Still, I wouldn't have thought that 6.5 would do that to you, but it makes more sense than anything else I can think of...

SpitfireS

It was per side
Apparently it is not that easy to convert mm-of-toe into degree.

ZDan

Not that any of us have been using mm, but it is super-easy. The convention is to measure at the tire OD. Tire is 24.8 in., that's 630mm. If toe-in is 3mm, then the angle is sin[sup]-1[/sup](3/630) = 0.27 degrees. Or 0.27[sup]o[/sup]*60 = 16' (arcminutes).

IMO, at 18 arcminutes, or 0.3[sup]o[/sup] total, you're where you want to be. If the computer was really giving a max of 30 arcminutes, or half a degree *per side*, 1 degree total, that's absurdly, ridiculously excessive.

SpitfireS

Well..
Driving around with L-0[sup]0[/sup]24' / R-0[sup]0[/sup]21' rear toe-in absolutely suxx big time!
The rear neg camber of L-2[sup]0[/sup]30 / R-2[sup]0[/sup]48 does not help either.

The "tech" that aligned the car was .. not very good at his expensive! job.
He said it was impossible to get right as the toe changed when he adjusted camber and vv...
I said: "Well.. that's how it goes.. right.. you have to adjust a bit more to get less toe-in?" but he answered it wasn't possible to get any better.
The idiot!

Slow speed turn-in is horrible, it is like the rear abrubtly turns-in the front, like oversteer without the rear loosing grip.
High(er) speed turn-in is ... defenitely NOT reassuring or comfortable, IOW it suxx too.
Straight line stability is bad and its tramlining way more than it ever did before.
Braking in a straight line is ok-ish, I just do not dare to trail brake even the slightest 'cause I have no idea what will happen.

Hopefully the alignment next week will get things right again.
And that's max -0[sup]0[/sup]08' rear toe in per side, rest per UK-spec.