MX5 SE Wheel alligment

[Luke]

Hi guys

Went in to get new tyres today + wheel allignment.

Tyres went on ok, but wheel allignment well that hasn't turned out to great.

I asked for these specs

Front
Caster 5 deg
Camber -1.10 deg
Toe -0.10 deg in need mm coversions

Rear
Camber -1.40 deg
Toe -0.15 deg in need mm conversions


Boy did this turn out a mess. Started doing the work, and the guy said its gonna understeer. He started at the rear and said he can't get the camber up to -1.40. It topped out -1.10.
So i said fair enough. He did the toe first.

He then went onto the front and put the caster at 5.4 each side. One side was allready 5.4 thats why he did this. He then did the toe and then went onto camber. He could not get it at all right. One side was -0.6 deg and the other -1.0 deg.


I then noticed the problem.
I gave him the toe values in degrees and his machine was using mm's.
From there i don't think hes fixed it right.
He put the toe at the front to 1mm in.
Toe at the rear to 1.2mm in.
I dont think he readjusted the camber after doing this which I'm asuming is now out of wackd ue to the change in toe.
Plus there was allready 0.4degrees of difference in camber to begin with at the front!


Now the car bloody hangs to the left. He drove it and told me it goes straight, I drove home didn't really notice it has any probelms since the roads to my place are either crucy or crap!
So tonight I went on a nice smooth bit of highway and found i have to turn a fair bit right to go straight!

I have about 2000km driving before the track day, mostly highway so that should scrub the tyres in a bit. But it has to be alligned properly first so I don't destroy them.


So in short I am calling tomorrow to complain/ask for the job to be redone, and I'll make sure the boss does it this time.


What I basically also want to know, will the settings I put at the top be ok for a trackday(Oranpark). The car is dríven spiritly (once warmed up of course) when doing normal road driving.
And is there a conversion from my degree specs of toe to mm. I just had a guess when the guy needed mm since it was close to the settings based in the charlie brown post on settings.

[OVERDRAWN]

Hi I have had a similar problem,a lot of wankers out there. My advice is to ask around and go to someone who has done a lot on 5's.The MX5 club or Mania might point you in the right direction
OD

[SPy vs. SPy]

Read This

Then get CTZooms alignment put on it. Good for Track and Road.

Note: JBT provides the conversions a few posts down

There are other specs that will be "awesome" BUT not for tyre life.

[Charlie Brown]

Luke,

Adjusting the toe won't affect the camber, so you have no worries there.

A couple of questions:

Which side has the -0.6 camber? The passenger side?

Were you allowed to sit in the car when the alignment was done?

Did he match the difference in L to R front camber to the rear camber on the same side? In other words, does the side with -0.6 on the front have -0.7 on the rear?

The reason I ask is if you were not in the car (or the car ballasted to match your weight) then the alignment guy should allow for that in the camber settings, giving you -0.2 to -0.3 MORE on the DRIVERS side.

I know this sounds crazy but next time you’re at the aligners check it out. Get him to set the car up without you in it and take note of the negative camber number on the driver’s side. Then stand on the door sill and have a look at the setting. It will go positive by the 0.2 to 0.3 figure.

So if he has done this the car will track off to the left with the camber of the road because the camber will be even across the car with one person in it. If you set the car on top of the crest, ie sits horizontal on the road, and it still steers left then I'd head back for it to be fixed.

Are your toe settings of 1mm in front and 1.2mm in rear, the total toe in or a per side value? If it’s the total figure it’s fine.

If you want more camber he will need to bring the castor figure down, just remember the lower the figure the less of the “centring” effect you will get with the steering wheel.

To understand castor think about a Harley Davidson Chopper with their forks sticking way out in front, miles of castor, vs a child’s three wheel bike where the forks are almost vertical, little castor.

Get back with the figures.

Hope that helps.

[Luke]

The -0.6 was the passanger side, the -1.0 was the drivers.

I asked if I could sit in the car and the answer was no. They put some sort of thing in the drivers side holding the brakes at first then I have no idea what the second thing they put in was.

The front and rear is lopsided in camber. I.e the rear has equal at the back one side was 1.06 and the the other was 1.09 can't rember which was on what side but yeah a tiny difference at the rear.


The car is hanging to the left regardless to the camber of the road, so I'm pretty sure a setting is completly mucked up.
Its re-booked in for Thursday afternoon(I'm not paying since the job wasn't done right the first time)


So basically i need the caster reduced a bit from the ~5.4 he put on to 5.

And camber fixed.

So is this about what I want and should ask for? And is that front camber possible with that caster, or does the caster need to be change a bit?

Front
Caster 5.00 deg
Camber ~1.10 deg
Toe - ~1mm in

Rear
Camber ~1.30-1.40 deg
Toe - ~1.5mm in


What I mostly don't like, is that I was told it drives straight after they took the car for a drive!
It was driving straight before though.
I'll give them one more go before I look else where for the job to be done.

[Charlie Brown]

So is this about what I want and should ask for? And is that front camber possible with that caster, or does the caster need to be change a bit?

Front
Caster 5.00 deg
Camber ~1.10 deg
Toe - ~1mm in

Rear
Camber ~1.30-1.40 deg
Toe - ~1.5mm in
.

The figures above are ideal for spirited driving and the odd track day but I’m not sure that you can achieve them. You can take off castor to increase the negative camber but generally you try to max out the castor (even both sides) then adjust the camber.

Try the 5.0 castor and see what you get with the camber. It might not change much, in which case just take the maximum on the drivers side and set the passenger side 0.2 degrees more positive.

Check that the front toe is even both sides for your “not steering straight” problem.

I asked if I could sit in the car and the answer was no. They put some sort of thing in the drivers side holding the brakes at first then I have no idea what the second thing they put in was.

.

What he put in your car was a bar to lock the steering wheel in the straight ahead position. No weight loading involved.
I have used 3 bags of river pebbles on the drivers seat to match my weigh when the aligner wont allow you to sit in the car but ask them if that’s OK first before you race out and buy some pebbles.

Enjoy Oran Park but don’t over drive. It’s an old style circuit that bites back when you make a mistake. You should join the MX-5 Club and come to Wakefield for even more fun and it’s safe with little chance of bending your car.

I have found with aligners that you really need one that knows his business.
I've used a few and the two that stand out are Stu at Spinning Wheel and Doug at Headsman’s.
Spinning Wheel has the entire whiz-bang laser set up while Heasman’s have the older style mechanical machine. Both set up race cars, both offer advice to achieve your handling goals

[Luke]

Ok

Thanks for the advice.

I allready have been to Oranpark once (the Sunday that just happened terrible weather!) so yeah I know the track bites.

2 skylines into the wall one at the back section and one at the last corner.

Had a couple off's my self. I blame the failry worn orignal Toyo Trampios for that, no confidence with them in the wet at all!.

And thats why I have gotten new tyres.


I will be joining the MX-5 club, from what i can remrmber membership is from October-October so thats really the only reason I havn't joined yet.

[Charlie Brown]

Membership is renewable in October but if you joined now (you pay full fare first up), in October you would pay a prorated fee for 3 months. ie for July, August & September.

[Luke]

Oh so thats how membership works, oh well counting is hard so I'll just join in October.

Anyway back from allignment and this time i got a print out.

Values before adjustment:

Front

Toe Left = +2.3mm Toe Right = +2.0mm

Camber Left = -1.11 Camber right = -1.04

Caster Left = +5.31 Caster right = +5.14

Back

Toe Left = +0.4mm Toe Right = +2.0mm

Camber Left = -1.26 Camber right = -1.22


New settings

Front

Toe Left = +0.8mm Toe Right = +0.8mm

Camber Left = -1.08 Camber right = -1.02

Caster Left = +5.30 Caster right = +5.22

Back

Toe Left = +1.3mm Toe Right = +1.1mm

Camber Left = -1.18 Camber right = -1.26


And still hangs to the left! From what I can tell in my short trip home.


My first q now is
When i ask for toe in should that be postive or negative?
I thought in would be - not +. I'm just guessing here though.
I did ask for in.


My car is going into Hume Smash on Saturday, and I;ve allready been told if the allighnment is still crap, they will send it to morebank pedders for a full check and allighnment under insuarance since it did go up a driveway pretty hard.

This comes back from 3 weeks ago when went up a driveway at speed and hit a steel post.
And from that I was turning a bit to the right to go straight.
The right wheel was pointing out a bit after this.
I got an allignment straight after that at the most old fashioned guy. Rex Staford Steering Suspension and brakes. He made it go straight! First go to. And found nothing bent. He just said the allignment was knocked all the way to the maximum.

They havn't said nothing at Jax about anything being bent either.

So now I'm just hoping either pedders gets the allignment right, or finds a part is bent!.

[Charlie Brown]

Your alignment doesn't look that bad. With that toe it should track down the road fine.

I'd have less toe but then my settings are more track orientated.

I'd get Mike at Humes to check it out because it sounds like there is something more amiss than the alignment.

[Luke]

Right same probelm still!


The car has been and gone from Hume they didn't find anything wrong.
They took it to pedders who also found nothing wrong.
They put less severe camber and toe settings in.

I go drive the car on some highways this week and it still goes left when you have the steering centred!

Its currently at MX5Mania getting serviced so they are going to have a look for me.


So does anybody have a recomended person/place in Sydney to see about this that has seen this problem on mx5's before, because it aint right.



Only thing I havn't tried which I might do on the weekend when I get the car from mania is to move the wheels around the car.
I'm just guessing it could be the tyres.
I am only taking this guess, since the first allignment at Rex straight after the accident made it go straight. This was still with the original tyres.
I even did a track day after this no problems on the old tyres.
Since the new tyres have been on it has been going left, but it also had another wheel allignment then as well.


Luke

[philz]

Go to Peter at Road&race performance @ Rydalmere, he will be able to help you with locating anything bent.

[SPy vs. SPy]

I go drive the car on some highways this week and it still goes left when you have the steering centred!

Luke

Is the wheel naturally centred or are you holding it centred?

If your holding it centred it sound like the tie rods need a tweak, an alignment shopshould have picked that though.

[blackster]

edit

[Charlie Brown]

OK one last measure to fix the problem.

If you have rotated your wheels and it still drives off to the left there is only one thing left to do and a good aligner should have suggested it to you.

You need to offset your castor, in other words have it greater by about 1 degree on the left side than the right, so it allows for the camber of the road and the car will run straight.
If you do this it will head off to the right on a flat track but if you’re hanging onto the wheel tight you won’t notice it.