CMiS2K

I could here them back the car in, out, in, out and then he drove around and said it was too low. He didn't have a problem with the alignment specs that I gave him. Supposedly several Miata owners have used this shop.

I decided to go with a full -2.0 of camber in the rear and a total toe in of -.4.

I am going to set up an appointment for Monday the 5th.

Wildncrazy

Or you can go where I go and they drive it up on a ramp and charge about $130 for a lifetime alignment and will align it as often as you like for $0 thereafter.

It's in Richardson

altiain

CMiS2k, the more camber you can get (up to a point, of course), the better. I run -2.2 front & -2.8 degress rear camber on my Miata, and it sees over 20,000 miles a year. Contrary to what many people think, excessive toe is much more likely to accelerate tire wear than excessive camber. As my negative camber has increased (I could only get -1.2/-1.8 at stock ride height) my lateral grip has increased and wear on my race tires has actually decreased, as I'm now using the entire surface of the tire and not just the outside edge. Consequently, my race tire expenses have decreased, as I no longer need to "flip" my race tires after every three or four events.

Like Gregg pointed out, a little bit of toe-OUT up front can help the initial turn-in response, but you'll also get the same transitory effect from a larger front sway bar, without the freeway-speed "wandering" that often comes with running front toe-out. Zero front toe is fine, or even a little front toe-in if you want a car that is very directionally stable at freeway speeds.

As for toe-IN at the rear, let your conscience be your guide. Does your car feel twitchy under trail-braking or does it seem to want to oversteer in steady-state cornering? If so, then a little more rear toe-IN could help stabilize the car a little bit. If your car is difficult to rotate - controllably - under trailbraking, then you might want a little less rear toe-in. You will never, under any circumstances that I can think of, want any rear toe-OUT. BTW, You can adjust the transitory behavior of your car with the shock damping adjustment of the JICs, but steady-state behavior will still be dictated by your spring rates, sway bars, and your alignment.

Also, a little tip for ride height measurements - if you measure from the hub center to the edge of the fenderwell instead of from the ground to the edge of the fenderwell, then it negates any differences in wheel size. In other words, it will allow you to compare ride height directly from car to car, without having to worry whether this car is on 17" wheels and such-and-such tires, and this car is on 16" wheels, etc. Just a little tip.

Oh, and David B - when it comes to alignments, you get what you pay for. I've yet to see a shop that would let me sit in the car, use my own custom specs on a lowered car, and could get it all right while offering a lifetime warranty. Most of those places will not offer any kind of warranty unless the car is fully stock and the alignment is fully factory, which means that they'll get it somewhere in the factory range. Thanks but no thanks, there is plenty of room for slop inside the "factory recommended" range.

CMiS2K, try DFW Frame and Alignment in Hurst, or Peterson's Automotive in Haltom City. Both are frequented by racers (as opposed to soccer moms), both will do custom specs, both will let you sit in the car, both should be able to get your car on the rack (they got mine up and I've got ~3" of front ground clearance), and both will do good work. They're also both relatively close to you.

Wildncrazy

Well, Altiain I get the best of both worlds, price and customizability.

I get to sit in the car and use my own custom specs and it is warrantied. They will try new things every day if I want them. He does alignments for many exotic cars and has a few ideas of his own, but he will use any specs you give him.

We have been working on a new alignement since I have different rims with different offsets than stock and so far in the last 6 weeks I have had 3 different alignments. I will be in today or tomorrow for a little tweak that I will run the 10th and see if that has got it where I like it again.

They have a drive up ramp so a lowered car is no prob.

Gernby

David b, what alignment machine does he have?

CMiS2K

I didn't want to throw any names around earlier, but DFW frame and Alignment is where I went. I don't know the name of the guy that was trying to put the car on the rack. He said it was too low. Billy reccommend them and figured if they can get a Miata on the rack, they should be able to get the S on the rack.

thanks for the tip on measuring ride height

Gregg Lee

Now that I live so far out of town, I do my own alignment. Slow but cheap and accurate.

I used to go to Dallas Frame and Alignment on Fabens in NW Dallas. Just west of Harry Hines. 972 241 2361. Their yellow pages ad says "lowered vehicles."

When I have been there, the service tech has always been involved in some sort of racing and was more than happy to have you watch or sit in the car and shoot the breeze. Their alignment racks are over pits so there is no safety issue with being in the car on a lift. No lift. They use optical guages, which in the hands of a competent operator are better than the computerized machines.

This is a traditional looking place. Gravel parking lot etc. Last time I was there, they were aligning a tow truck with a car on the hook to get proper in service conditions.

Gernby

[QUOTE]Originally posted by Gregg Lee
[B]Now that I live so far out of town, I do my own alignment.

Gregg Lee

No reason to wait on bar.

In fact be sure to disconnect both sway bars before you do corner weights or ride height. Other wise the sway bars will fight back against adjustments. And remember that the only thing you are trying to do with spring perch adjustment besides ride height is to get diagonal weights the same (within 10 lbs anyway).

After you have adjusted corner weight and ride height, then reconnect the sway bars, adjusting the end links so the bars are neutral.

Gregg Lee

(typos corrected.)

Well first I have had lots of practice on my Formula Ford.


I find my measurements are repeatable to 0.1 degree.

I have a good camber gauge. I think I got it from Pegasus, but lots of places sell them. They typically have a bubble level attached to threaded adjustment with wheel marked to 0.1 degree increments.

Camber is camber.

To do caster, you measure camber with wheel turned the same angle in and out (20 degrees is pretty standard.) Use a lookup table or calculate caster from difference in the two measurements and the angle used. Once I did the geometry I made a table on excel.

Toe. Lay a board in front of the tires and mark a selected spot on the tread on each side. Then do the same on the back side. You don't need the absolute distance, just the difference. A 2 inch board hits the tire just about at rim diameter. If you are uncertain of measuring point on tread pattern, then put a piece of masking tape on the tread to measure one side, then roll the car over it so it comes up on the other side and remeasure.

Stack cheap floor tiles to create level wheel pads. They also provide enough slip to allow turning the wheels for the caster measurement.

The slow part is that you have to jack the car to do adjustments, then roll back and forth to settle suspension before next measurement. And of course, front camber changes front toe, and in the rear toe may affect camber given the adjustment method. So be sure to do things in the right order and recheck when done.

With eccentric bolts you are estimating adjustments much more than with nice threaded rod ends found on a formula car, where you can accurately predict degrees per turn, and usual hit the adjustment on the nose the first time. I am developing an eye for adjusting the eccentric bolts. While adjusting don't look at the bolt, look at the suspension arm versus the bracket.

The only tricky adjustment is rear toe. You want to keep sides equal. With front toe, this isn't a problem, since you will immediately notice the steering wheel off center. Actually if you have done front first, then a rear toe centering problem will also cause the steering to be off center since front wheels must correct rear steer. But it's more direct to lay an 8 foot board across the rear tire side so the front of the board is on the ground just behind the front tire. With the S2000 the body does not interfere. This will not be true on all cars. You want the end to be inside the edge of the front tire by the same amount on both sides.

Order:
front camber, front toe, front caster (which honda claims will not affect camber, but I would recheck)
finish front before starting rear.

rear camber, rear toe, verify toe centering, repeat until no change.

With the formula car you could also adjust rear caster and bump steer all around, but these are not adjustable by ordinary means on the S2000.

Suspension adjustments are tedious because they interact. Be prepared to be patient.

Gregg