Toe in, camber and caster adjustment?

[Sonus]

My Vixen is slowly getting the attention it needed. However I am concerned the wheel angles are out of adjustment.

Does anyone know what the original numbers for front and rear toe in/out, camber and caster were?

Are there any changes that should be done to these numbers when using modern tires?

What is ideal ride height for road use?

I have some bump steer. What can be done to reduce this?

I'm booking the car in for 4 wheel alignment and would like to have it set up properly.

[Astacus]

The figures were given by Steve Reid in a 2005 posting

I quote

Friday 27th May 2005
Quoting from factory owners manual:---FRONT Castor angle fixed; Camber angle half to one and a half degrees Positive: Front wheel alignment Toe in 20 minutes:: REAR Camber angle one and a half to two degrees Negative; Rear wheel alignment Toe in 30 minutes sTeVeR

As he says the castor angle is fixed by the offset between the top and bottom mountings of the uprights. You can see that the top wishbone at the front is not symmetrical

I should mention these figures were not for an S1

[Sonus]

Thanks Astacus

I wonder what 20 and 30 minutes mean?

Also slightly confused about positive camber on the front and negative in the rear.

But it certainly gives me a starting point.

Might k ask what car they were given for?

[Sonus]

Sonus said:

Thanks Astacus

I wonder what 20 and 30 minutes mean?

Also slightly confused about positive camber on the front and negative in the rear.

But it certainly gives me a starting point.

Might k ask what car they were given for?

For future reference I googled "toe in measured in minutes" and foind that 60 minutes is 1 degree

That makes it 1/3 degree front and 1/2 degree in the rear

[Slow M]

Tjere are 60 minutes in a degree and 60 seconds in a minute.

So, .333 to .5 of a degree.

Best,
B.

[ATE399J]

OK, having established 60secs in a min and 60mins in a degree and 360degs in an hour (or something like that), the next obvious question I guess will be in regards to the conversion to the usual modern method of defining toe-in in mm.

I guess simple geometry is the answer which would give about 2.2mm assuming one measures at the wheel rim... Does this seem right?

Edited by ATE399J on Tuesday 10th June 22:25

[davegt6]

OK so we are talking road car set up here but I still don't like the sound of positive camber on the front wheels particularly as there is next to no castor built in to the chassis geometry. It will certainly make the steering light at parking speeds but won't do anything for higher speed handling and I'd expect a lot of understeer and associated tyre scrub but if you're just pootling around I suppose it would be OK.

[Slow M]

Tjere are 60 minutes in a degree and 60 seconds in a minute.

So, .333 to .5 of a degree.

Best,
B.