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camber problem
robertst - 7/3/07 at 04:41 PM

mounted the front axle today and my happiness swiftly ended when i relized the top wishbone seemed too short to let the upright be vertical.

is there a way i can remedy this? in the pic, the ball joint is at its maximum and even so, the upright is horribly tilted. Rescued attachment camber.jpg
Rescued attachment camber.jpg


Schrodinger - 7/3/07 at 04:53 PM

The bottom wishbone looks rather long and the steering rack looks as if it will have difficulty reaching the hub.


flak monkey - 7/3/07 at 05:01 PM

From the looks of your bottom wishbone mount at the rear, it looks like it is hanging outside of the chassis by about an inch? It should be well on the chassis rails. And of course the wishbone pivots should be parallel to the centreline of the car.

I would suggest that your bottom wishbone mounts are too far outboard for some reason.

Those are GTS 'bones arent they? Did you tell GTS you were using them on cortina uprights? The wishbones are different for cortina and sierra uprights (I know 'cos i had to have some made)

David

[Edited on 7/3/07 by flak monkey]


stig mills - 7/3/07 at 05:03 PM

It looks like chopping off the bottom mounts and moving them in may be the cheaper option. Track width will reduce though, regards Stig Mills


Jon Ison - 7/3/07 at 05:12 PM

Agree with Flak Monky, those btm wishbone brackets are well outside the chassis compared too mine, mine are that far inboard I also welded them too the two inner chassis rails that triangulate the engine bay, sorry book long passed on so don't know tube numbers.
Also for safety reason don't even think about running with that much thread showing on the top ball joint, track rod end thingy.

The chassis is pretty bare at the mo, will take a pic if I can.


andyps - 7/3/07 at 05:15 PM

Are they bones designed for use with Sierra uprights, but Cortina uprights?

[Edited on 7/3/07 by andyps]


MikeRJ - 7/3/07 at 05:24 PM

quote:
Originally posted by andyps
Are they bones designed for use with Sierra uprights, but Cortina uprights?


Was going to post exactly the same thing. The bottom brackets would have to be moved inboard a huge amount to get camber to reasonable level AND get most of the balljoint thread back into the top wishbone.

The bones do look very long though, perhaps it's just camera angle or something.

[Edited on 7/3/07 by MikeRJ]


Jon Ison - 7/3/07 at 05:24 PM

Lower bracket, sorry bout out of focus. Rescued attachment topjoint1.JPG
Rescued attachment topjoint1.JPG


Jon Ison - 7/3/07 at 05:25 PM

Top swivel joint........ Rescued attachment topjoint.JPG
Rescued attachment topjoint.JPG


mistergrumpy - 7/3/07 at 05:50 PM

Ah. You have Cortina uprights on Sierra width wishbones. I had it the other way here You can see that my upright was hanging the other way. As Calvin says on the thread, the top wishbones are the same, its the bottom ones that are different lengths. I had to get correct length bones and then, as I suspect you may have to do, I had to hack off and then reweld some of the brackets that I had fully welded! I did get away with one or two though.


robertst - 7/3/07 at 07:10 PM

there is no sierra / Cortina choice in GTS website. it just has regular "Book" wishbones and W7DE wishbones. i bought GTS 552b ones which.... OH! WAIT A TICK! i know what happened!.

the bottom 'bones are ok. but according to GTS's website there is only one option available for the top wishbones so logically these top wishbones are made to the book dimensions, whereas, the W7DE ones should have included longet top wishbones aswell!

so its a matter of declaring my top wishbones useless and trying to make my own top wishbones (which is exactly what i did not want to do (hence why i bought them).

So i think the cheapest option would infact be to make my own top bones.

do u agree? i mean i dont want to fiddle around with the chassis anymore. i might reconsider moving those brackets inwards as, i agree, they don't look very safe to me... plus they will end up interfering with the bodywork!

oh my god theres so much work to do!

searching around the forum, i found that the tube diameter for the wishbones is 1 inch. is that correct?
i would think it is 3mm wall.. any info on this?

thank you all for your help.
Tom

[edit: ok.. basically what mistergrumpy said.. cheers mate!]

[Edited on 7/3/07 by robertst]


robertst - 7/3/07 at 07:26 PM

Right now i see two options:

1) make a longer top wishbone

reading mistergrumpy's thread, someone said cortina wishbones are somewhere near 30mm shorter than sierra ones so:

2) shorten the bottom wishbones (probably 30mm, maybe a bit more). a cut and weld job.

i'd acutally prefer not to fiddle with the bottom wishbone as if you look towards the background, the hub is almost perfectly aligned with respect to the back (although there's no rear axle yet). IMO track width is spot-on.

so i probably prefer the first option. do you think it's feasible to replicate the top wishbone, but longer?

thanks again

[Edited on 7/3/07 by robertst]


caber - 7/3/07 at 09:53 PM

you can make new wishbones but forget the jig info in the book it will not give you a sufficiently accurate result. The new book has a lot about wishbone jigs in it. you need to start with a very solid metal frame to weld the 'bones in otherwise they will distort. you also meed an M18 tap to make the thread in the tube. these are expensive so if you can't borrow one you may be better to just buy a new set of top bones and try selling your existing ones here or ebay!

I had the problem in reverse so I had to chop a chunk off my top bones that were all nice and powder coated


Caber


ProjectX - 7/3/07 at 10:15 PM

quote:
Originally posted by caber
you can make new wishbones but forget the jig info in the book it will not give you a sufficiently accurate result. The new book has a lot about wishbone jigs in it. you need to start with a very solid metal frame to weld the 'bones in otherwise they will distort. you also meed an M18 tap to make the thread in the tube. these are expensive so if you can't borrow one you may be better to just buy a new set of top bones and try selling your existing ones here or ebay!


Caber


I agree wih the idea, however watch the thread M18 some transit are M20!

Threaded tubing can be got on Fleabay for a couple of quid.

With the bones if you need to weld your own

1. Something flat
2. Keep the (chassis end) bushes together. ie use a piece of tube for the bush tubes then cut to size afterwards

HTH J


robertst - 7/3/07 at 10:20 PM

quote:
Originally posted by caber
you can make new wishbones but forget the jig info in the book it will not give you a sufficiently accurate result. The new book has a lot about wishbone jigs in it. you need to start with a very solid metal frame to weld the 'bones in otherwise they will distort. you also meed an M18 tap to make the thread in the tube. these are expensive so if you can't borrow one you may be better to just buy a new set of top bones and try selling your existing ones here or ebay!

I had the problem in reverse so I had to chop a chunk off my top bones that were all nice and powder coated


Caber


i dont need threaded tubing, i have the camber adjusters which i WILL reuse. current wishbones dont have a threaded tube.

[edit:] you had to cut a chunk out of your top bone? i would have to do the same thing for my bottom one, but im very weary of weakening the entire wishbone.

how did it go for you?

cheers

[Edited on 7/3/07 by robertst]


ProjectX - 7/3/07 at 10:25 PM

quote:

i dont need threaded tubing, i have the camber adjusters which i WILL reuse. current wishbones dont have a threaded tube.



So if not what does your ends screw into??


Dont cut the bottom bones, extend the top ones. The camber adjusters have nothing to do with it!

HTH


robertst - 7/3/07 at 10:31 PM

errr.. yes they do, thats how my top ball joint is held with! let me show you:
the wishbone itself does not have a threaded tube, it is the camber adjuster (gold thingy) which is slid from behind and locked with the ball joint nut...


ProjectX - 7/3/07 at 10:37 PM

quote:
Originally posted by robertst
errr.. yes they do, thats how my top ball joint is held with! let me show you:
the wishbone itself does not have a threaded tube, it is the camber adjuster (gold thingy) which is slid from behind and locked with the ball joint nut...


Mmm Ok I see what you mean! Not sure I would trust that idea of a Gold Thingy, but I cant say I know how it works! Not sure it would pass SVA in UK!

Anyway my point is change the upper bone will be easier and keep the track same

J


MikeRJ - 7/3/07 at 10:47 PM

The GTS-552b wishbones are for the "wide track" option which (AFAIK) you would normally use on a standard width chassis to match the track of the Sierra rear suspension. Putting wide track wishbones on a +4 chassis is going to give you an enormous track, which explains the discrepancy in you steering arm lengths. I think the 552a bones would have been the correct choice.

Also, I thought the GTS wishbones were designed for use with the Sierra upright which is what their own cars uses, though I may be wrong.


MikeRJ - 7/3/07 at 10:50 PM

quote:
Originally posted by ProjectX
[Mmm Ok I see what you mean! Not sure I would trust that idea of a Gold Thingy, but I cant say I know how it works! Not sure it would pass SVA in UK!


Why would it not pass SVA providing the edges were protected? Many of them have already passed with no problems. It's a superior solution to the standard design as you don't have to remove the ball joint to adjust camber, and you can adjust it as little as you want (standard system has to be adjusted by one complete turn at a minimum.


andyps - 7/3/07 at 10:53 PM

quote:
Originally posted by ProjectX
quote:
Originally posted by robertst
errr.. yes they do, thats how my top ball joint is held with! let me show you:
the wishbone itself does not have a threaded tube, it is the camber adjuster (gold thingy) which is slid from behind and locked with the ball joint nut...


Mmm Ok I see what you mean! Not sure I would trust that idea of a Gold Thingy, but I cant say I know how it works! Not sure it would pass SVA in UK!

Anyway my point is change the upper bone will be easier and keep the track same

J


Pretty sure the camber adjust would be acceptable for the SVA - basically it locks on the outer end, but when loosened off can be adjusted from the inner end. This allows fine adjustment of the camber, unlike a conventional type which can only be adjusted by multiples of a complete turn of the thread. Alan Staniforth uses this method in his competition car suspension book. I suspect it also removes the chance of thread distortion when welding threaded tube for the link. All in, a nice way to do it, but not the root of the problem being faced here.

[Edited on 7/3/07 by andyps]


James - 8/3/07 at 12:35 PM

Passed my SVA fine with it.