Adjustable wishbones - camber / castor

[lambostylus]

To go back to my original thread, I didn't explain very well

The lower wishbone is probably a test-and-adjust set from when the RT was being developed.
- One arm is slightly bent (and reinforced), to give more of an angle for the lower ball joint.
- but the other arm attaches by an M14 bolt/locknut to form the Y shape.
- This second arm has a screwthread and lock-off nut to adjust the length.
- The two chassis ends of the wishbone are attached by M14 bolt/locknuts to the end of the wishbone arm.

In this way it has about 4 degrees of movement (or 4 hinges).
The actual length of the arm can be adjusted, and wasn't set when bought, so the castor could be way out. i've set the castor by ruler and spririt level as best I can, but essentially I think can adjust the entire steering geometry.
This is a little out of my league = need help.

[stylussprinter]

To go back to my original thread, I didn't explain very well

The lower wishbone is probably a test-and-adjust set from when the RT was being developed.
- One arm is slightly bent (and reinforced), to give more of an angle for the lower ball joint.
- but the other arm attaches by an M14 bolt/locknut to form the Y shape.
- This second arm has a screwthread and lock-off nut to adjust the length.
- The two chassis ends of the wishbone are attached by M14 bolt/locknuts to the end of the wishbone arm.

In this way it has about 4 degrees of movement (or 4 hinges).
The actual length of the arm can be adjusted, and wasn't set when bought, so the castor could be way out. i've set the castor by ruler and spririt level as best I can, but essentially I think can adjust the entire steering geometry.
This is a little out of my league = need help.

Didn't know Tim sold any of those. He fitted them to the red demo classic Stylus and also on the RT demo car --- however , under track pressure at Enstone with me , a few years back , one side bust blowing him off track --- fortunately into grass run off.
I'm not comfortable with them myself and he reverted back to fixed wishbones or rose jointed adjustment as a factory extra.

[lambostylus]

I might just weld the thing in place once set then.
The trick will be to get the settings right.

[lambostylus]

Just back to this topic again, setting up before the IVA. The next time someone takes a tyre off, please have a look and tell me if you have positive or negative castor on your steering geometry. I've found the clubstylus page says to turn the wheel one rotation and set to negative 3.5 deg of castor... but modern road cars are supposed to have positive castor aren't they?

is this a typo, or have I got the wrong end of the stick (at 1 a.m.!)
cheers aye

[stylussprinter]

Just back to this topic again, setting up before the IVA. The next time someone takes a tyre off, please have a look and tell me if you have positive or negative castor on your steering geometry. I've found the clubstylus page says to turn the wheel one rotation and set to negative 3.5 deg of castor... but modern road cars are supposed to have positive castor aren't they?

is this a typo, or have I got the wrong end of the stick (at 1 a.m.!)
cheers aye

Well let's get down to basics. The top pivot should be behind the bottom pivot . Not sure if you have Seirra or Escort M2 uprights but the direction is the same , just better geometry on the Escort. I'll measure mine -- top to bottom and let you know ok. Don't worry about having more than 3.5 just don't set less . It gives stability at speed plus better steering return.
Rob

[lambostylus]

Well let's get down to basics. The top pivot should be behind the bottom pivot . Not sure if you have Seirra or Escort M2 uprights but the direction is the same , just better geometry on the Escort. I'll measure mine -- top to bottom and let you know ok. Don't worry about having more than 3.5 just don't set less . It gives stability at speed plus better steering return.
Rob

Thats exactly what I thought it should be, in which case can someone please amend the car setup section of the clubstylus homepage, which states "If you have adjustable bottom arms set the castor by turning the steering wheel to one turn (approximately 20 degrees at the wheels) and set the corner's outside wheel to 3.5 degrees negative."

Negative castor is where the top pivot is in front of the bottom pivot
As always stylussprinter, your help is much appreciated. I take it you set the castor before the camber, or does this result in a bit of tail chasing to get the right angles?

[Bikenuts]

Well let's get down to basics. The top pivot should be behind the bottom pivot . Not sure if you have Seirra or Escort M2 uprights but the direction is the same , just better geometry on the Escort. I'll measure mine -- top to bottom and let you know ok. Don't worry about having more than 3.5 just don't set less . It gives stability at speed plus better steering return.
Rob

Thats exactly what I thought it should be, in which case can someone please amend the car setup section of the clubstylus homepage, which states "If you have adjustable bottom arms set the castor by turning the steering wheel to one turn (approximately 20 degrees at the wheels) and set the corner's outside wheel to 3.5 degrees negative."

Negative castor is where the top pivot is in front of the bottom pivot
As always stylussprinter, your help is much appreciated. I take it you set the castor before the camber, or does this result in a bit of tail chasing to get the right angles?

I think what its saying is adjust the CASTOR to give 3.5 degrees negative CAMBER when the wheel is turned in 20 degrees – positive castor gives an increases in (negative)camber as the wheel turns in – in extremis if you could turn the wheel 90 degrees then you’d add (negative)camber equivalent to the castor angle.

[stylussprinter]

Well let's get down to basics. The top pivot should be behind the bottom pivot . Not sure if you have Seirra or Escort M2 uprights but the direction is the same , just better geometry on the Escort. I'll measure mine -- top to bottom and let you know ok. Don't worry about having more than 3.5 just don't set less . It gives stability at speed plus better steering return.
Rob

Thats exactly what I thought it should be, in which case can someone please amend the car setup section of the clubstylus homepage, which states "If you have adjustable bottom arms set the castor by turning the steering wheel to one turn (approximately 20 degrees at the wheels) and set the corner's outside wheel to 3.5 degrees negative."

Negative castor is where the top pivot is in front of the bottom pivot
As always stylussprinter, your help is much appreciated. I take it you set the castor before the camber, or does this result in a bit of tail chasing to get the right angles?

OK , I've measured mine re- the difference between top and bottom because mine was set up using equipment that's not available today. You need to remember that mine are basically Cortina geometry not Seirra or Escort but the principal is the same. The top centre pivot is 45mm's behind the bottom pivot - ie. top is closer to the rear wheels --- bottom is closer to the front bonnet hinge
When you drive it , the castor set will become obvious . The steering wheel should return from a full lock on cornering and slip through your hands as you release grip BUT --- the major thing will be stability or NOT at speed , say 70 to 90 mph. If there's enough castor you'll notice NOTHING , if there's not enough , you'll have great difficulty keeping it running straight even though you are on a straight road and not moving the wheel --- you wont like it , it's bloody dangerous --- been there , done that
Regarding setting up ---- it's castor/camber then toe because castor will alter camber and camber will alter toe ok
We'll leave Ackerman alone for now because it's set by design and unless you change as I have done , to a totally different front end then it can't be changed anyway.
Ideally , the ''lines'' drawn along the angle of both steering arms should meet in the middle of the rear axle . I wont go deeply into it here but a search on google will explain in great detail the advantage of getting it right

Sorry to interupt your chat with the BOSS

[Camoradi]

Sorry to (slightly) hijack this thread, but a question on this topic. I read lots of information about how "Cortina Geometry" is superior to Sierra, and just looking at Sierra uprights confirms this

My question is, would original Cortina uprights be suitable for a stylus?, as opposed to MK2 Escort / new alloy uprights? I've found a source for Cortina bits whereas Mk2 Escort bits seem to rare / expensive / both.

[stylussprinter]

Sorry to (slightly) hijack this thread, but a question on this topic. I read lots of information about how "Cortina Geometry" is superior to Sierra, and just looking at Sierra uprights confirms this

My question is, would original Cortina uprights be suitable for a stylus?, as opposed to MK2 Escort / new alloy uprights? I've found a source for Cortina bits whereas Mk2 Escort bits seem to rare / expensive / both.

If you change to Escort ally uprights everything will be as before - simply lighter. Whereas if you change to Cortina geometry , the car will automatically be 20mm lower at the front due to the stub being 20mm higher on the upright --- quite an advantage . Having done that , you'll need to be able to adjust the wishbones on all three corners to get the castor right. Well worth the effort though. The castor built into the standard Stylus design ie. Escort uprights/wishbones to suit , means you have to be able to adjust the wishbones to achieve the castor required for Cortina geometry.
You could of course use Triumph uprights , also very light weight but the wishbones would need to adjust likewise -- rod ends being ideal
Rob

[Camoradi]

Thanks Rob.

As an aside, I spent yesterday evening measuring up some Mk 1 MX5 front uprights (used on some Westfields). They look like a possibility, but happily accept Ford wheel fitments.

Probably just opening a different can of worms though

This seems to be the biggest drawback with them, the angles of the pivots...

http://i543.photobucket.com/albums/gg47 ... dangle.jpg