Wishbone advice please

[Stu J]

Just having a problem getting the n/s to self centre after a brief road test, the o/s straightens beautifully.
The sva is not far away so I'd thought I would investigate further, all the mods have been carried out which just left the bottom wishbones to examine. I found the n/s wishbone bracket had been welded about 3/4" behind in comparison to the o/s which obviously meant the wishbone lost alot of angle through this compared to the o/s... I don't need this

Do those brackets have to be welded to the chassis?

Take a look and compare yourselves, this could be why alot of pilgrims have problems with the suspension.... it's shoddy workmanship

[stevem]

Hi Stu, Mine was exactly the same. Must be meant to be like that, after all they are put together on a jig?. Got mine to self center for SVA (in the end) HTH Steve.

[Stu J]

Hi Steve, I remember the interesting reading you posted with your car, how exactly did you conquer yours after numerous efforts?

I find it hard to believe the chassis are welded on a jig because I have measured differences between the n/s and o/s which can be as much as 1" out. The geometry of the steering rack could not be square and there would be no reason I can think of to make the chassis like that.

Because of the bottom bracket being behind, a certain amount of castor will be lost when all other mods have been stretched to limits in order to get that 'little bit', and would also explain why the self centre is not so effective on that side.

I would certainly start thinking the wishbone brackets needed to be set 10mm forward if I was put in charge for a day

[Steve]

could it be that the brackets are square......... but the chassis is not?

[Stu J]

Originally Posted by Steve

could it be that the brackets are square......... but the chassis is not?

That goes against the jig senario too, from my engineering background you need precision to be precise.

[Rowly]

Hi Stu & Steve
First thing I did was to check mine out, apparently on mine the distance between the wishbone bracket & the angled side member look the same.
So I also checked the measurement from the front end of the chasis to the brackets, and also the distance between each bracket. mine are all with 1mm. my chasis was made december 2005.
It is possible that the Angled side member is slighty out, which whilst annoying, is not as critical as the position of the lower wishbone.
best to check all dimensions before trying to alter anything.
I did a previous post about my steering rack. If you are using a P100 rack, this has got about 24mm more overall travel than a std Sierra rack, which can make the self centring difficult to fully acheive. ( I restricted the movement with Jubilee clips) But at the test they didn't reallly pay much attention to this item.
I am going to strip my suspension down, to reconfigure the castor angle, as has been suggested, I have done about 400miles & already got a bit of uneven tyre wear. I am also going to lower the rack to improve Bumpsteer. I tend to get a lot of "feedback" through the steering wheel, of bumps in the road. I am assuming that if the wheel movement is excessive relative to the steering arm, then this would be fed back up through the steering column. ? any comments anyone??.
Anyway good luck with lining up the wishbone brackets, I guess the most accurate way to do it would be to get it measured relative to the rear wheels (trying to ignore what happens in between)

[stevem]

The reason the brackets are of different measurements are so the front wheels sit centrally in the front arches. Go and measure the front wings. The O/S is longer than the N/S. (i kid you not) Cheers Steve.

[Rowly]

Steve,
You realy got me worried now
I rebuilt My garage last year to house my new Sumo, and thought I had made sure it was acccurate, but somehow the car looks on the "gimp" when it is in there, I assumed it was my garage a bit out, or the onset of "age related Fisheye".
Now you tell me the wings are different sizes, I dare not measure them....
If I had known, I would have made the garage to fit!!!
Rowly

[stevem]

Go ON, Go and measure them, you know you want to..

[Stu J]

From the front of my chassis the first wishbone bracket on the (good) o/s is 100mm, compared to 115mm on the n/s.

The suspension upright on the o/s is 40mm away from the rear wishbone bracket, compared to 45mm away on the n/s.

The cross member between the front chassis which has the steering rack mounted its different either side so that geometry can't be right.

Assuming however the chassis IS supposed to be like that why would you need to achieve different calculations in order to get the steering and suspension set when the welds are clearly different?