Sorry about the long story, but it adds some background as to why I'm a little frustrated.

My recent S2000 alignment adventures are as follows. Every time I have brought a printout with the "Honda UK" specs with me and given that to the service advisor. I will only mention the front since the rear has no probs.

First try with Dealer
Receive the car aligned to;
Caster -6.0
Camber -0.7
TOE 0.0
I asked; "why not as I specified" and the response was; "this is factory spec. we will not do any others, yada yada..." Hmmm, thanks

Second try now at a performance tyre dealer #1;
Receive the car aligned to;
Caster -4.0
Camber -1.3
TOE +0.2 (toe-out)
Again, I ask why not as I specified? Response; "this is as per our experience a very good alignment for racing." Thanks again.

Next day we had a "Fun autocross" = no points counted for the season and I was the fastest S2000 by 0.01s. So I guess the alignment is a racing alignment... Anyway, the car behaves VERY nervously, slightest bump in the road makes it twitch = me not happy

Third try again at performance tyre dealer #1, told them to DO the alignment as I specified
Receive the car aligned to;
Caster -4.3
Camber -1.0
TOE 0.0
Explanation this time "Caster is maxed out, no more possible"

Car feels less twitchy, actually good, but I miss a little of the "weight" in the steering from the caster. So I take the car in again;

Third try at performance tyre dealer #2, I look at the mechanic doing the adjustment and it really appears that the -4.3 is the MAX he can adjust caster to. I verified this myself, turning the "caster bolt" to its extreme position only gives -4.3?!

Now, at long last, my questions are;
-Is any other bolt used for caster adjustment except the "rear" adjuster on the front lca?
-Does the camber or toe adjustment somehow change the caster?
-Is my car car damaged/faulty?

Sorry, I dont have the service manual (ordering it now) so maybe there is an easy answer. All advice is greatly appreciated.

Thanks

Matt

 

[QUOTE]Originally posted by DesertRat
[B]
Now, at long last, my questions are;
-Is any other bolt used for caster adjustment except the "rear" adjuster on the front lca?
-Does the camber or toe adjustment somehow change the caster?
-Is my car car damaged/faulty?

Sorry, I dont have the service manual (ordering it now) so maybe there is an easy answer. All advice is greatly appreciated.

 

Right, I was told that increasing negative camber reduces the amount of caster possible. The tech told me that with -1 camber the most he could get was 6.1 caster on my car.. which I thought was a pretty good compromise (I had asked for -1.2 and 6.45).

 

Check the equipment they are using. I have found that the alignment machine made by "Hunter" is the only way to get an accurate reading on this cars set-up. The machine allows the operator to do all four wheels irrespective of each other (which no other machine can).

Utah

 

I have had a similar experience with my alignment shop, but worse is that the caster is different left to right. Final setting was camber -1.5* both sides, zero toe, but caster 6.7* Right and 5.0* Left. He even followed the Helm's manual but said that 5* was the max he could get on the Left. With camber and toe being the same Left and Right, why should there be a difference in possible range for caster? Anyone with similar experience, and will this difference in caster meaningfully affect handling (alignment guy said it won't)?

 

Thanks guys, appreciate the advice.

Z06-KILLR & cdelena
Good to know about the camber/caster relationship and I suspected as much, but I only have -1.0 camber and can still manage only -4.3 caster

Utah
I don't know the brand of machine he used, but it looked brand new, it did let him adjust one wheel at a time and constantly kept us all updated on changes at all corners (eg. me getting in-out of the car changed the settings)

rlaifatt
My alignment guy also said that caster does not matter that much, but eg. Puhn in his book "How to make you car handle" states that caster IS important.

 

For the sake of clarity, I was asking if the difference in caster Left to Right would adversely affect handling (not lower but equal caster left to right).

 

rlaifatt, if the caster numbers are unbalanced side to side (I believe this is what you are asking) then as your steering angle changes, your camber settings will also change as you steer. The caster is measured with the wheels turned at an angle to the car, and it should be fairly balanced. I do not know why some of the above numbers are so far off, but it requires adjusting the camber again if the caster isn't a big enough number.
In reality,with this car, I am not sure how much the caster variation affects this car. If you had a manual rack, you might be able to feel the turning resistance, but with our numb steering, there really isn't a lot of feedback. The fastest lines have to be sensed through the eyes and the butt-o-meter. The slight toe out mentioned above does have an effect on turn in, and works great if you don't go too far with it. Otherwise, the car will get twitchy on the road following irregularities. If the mechanic can't get the caster numbers in line, he needs to back off the camber and start over, maybe reversing the order in which he does the settings. I don't think anyone got the "Hey, Toshiro, let's cut some threads off this adjusting link, hahaha," routine. In other words, it's not the car, it's the mechanic.

 

Thanks chipperman. I'll have him do the caster first before finalizing the camber. Also, I might try a different alignment shop.

 

This happened to me. I took my '02 to a shop that said they would do the alignment to my specs, with me sitting in the car, on their nice, new Hunter. I printed out some specs from pfb's alignment settings thread, and they were something like this:

Front Camber: -1.0
Front Caster: 5.8 (+/- ?)
Front Toe: 0
Rear Camber: -2.0
Rear Toe: .25 in

The guy struggled and struggled to get my right front caster to what I wanted, but it only got up to 4.x degrees. He showed me that he couldn't get the bolt to turn any further, so I went ahead and accepted it.

About a month later, I found that he hadn't tightened the adjusters back down, so I turned the adjuster to about the same point that the other one was, and took it back. This time, he had no problem getting the caster to 5.8 degrees. Basically, he was turning the adjuster the WRONG WAY. I now know that my MINIMUM caster is around 4.x (when my camber is -1.0).

The mechanic was pretty embarrassed.