Rear Suspension Geo

Soooo surely if this is a good solution then having these made is a much better prospect? What are the length and diameter?

Trevor.

Well yes I can get them made no problem .If there are enough takers ?
I don't need any for JIL as that is having a whole new custom setup .It would have to carry a disclaimer though .I work with reputable engineers but this is a high stress loaded component .

Be nice to get some done as would make life very easy but unless we know these are up to the job the no good at all. It's the disclaimer the concerns me but if course I appreciate your position.

Trevor.

They will be sold under a disclaimer from any source
The concept is to use a smaller diameter to allow adjustment but of course this is then the load bearing area .Renault fit a 14mm bolt but this will go down to 12 or so at the load point to get the required movement .
Renault fitted a 14 based on xyz calcs .I'm just pointing out that this is the way they work .The ones Camskill sell will be no different to anything I can get made and be under the same constraints
It's all basic engineering stuff about heat treatment and stress raisers to limit any possible breakages but shit does happen when you start playing

[mettersl]

I have some for patterns if you need them, but as they are in compression and a failure is pretty much impossible, a disclaimer seems conservative but understandable maybe.
The shim I'd like the the caster adjusting one for the front suspension, it goes in front or behind the lower "wishbone"- does any body have one to copy?
Cheers
Lee

Yes I'm sure they'll be fine and as they are a std fix to the problem must not be prone to failure but ....We seem to be living in a far more litigious world these days ..........
The tuning fork/washer assembly ? I have plenty .

[mettersl]

page 31.011 of the parts book, item 29. 60 01 007 390....

Its more of a fork with a lip on it.

.
I think the load case is more complex than it's just in compression. Primarily as a fasteners it's in tension with no other loads applied, but when the wheel hits a pot hole, the reduced shank section will be in shear. So the failure mode does exist and not impossible to achieve. I think the lower fasteners on the hub / wishbone pivot on the GTA have sheared in the past; I'm sure Lee had one come in with it hanging off, and essentially this is the same failure mode. I think in fairness to Lee considering the risks, and consequences of the that particular failure event, say on a bend, on a wet day, giving a lift to the bosses pregnant wife... calibrated against the fact the world has just end, and it might be a full moon... Then the simple way is it's fitted at the owners risk and for racing purposes only ;-p

... I know shut up Faulks

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[mettersl]

Mr Faulks...I was talking about shims for rear wheel toe out, not the camber adjustment when I said I had patterns and they were low risk as they are shims in compression.
Offset pins at the top pivot (doesn't that also carry the spring loading?) is definitely a reduction in strength and something to be thought about carefully.

.
Sorry, I should be more observant .

Yes you're right, zero risk in the shims, .. As to the camber bolt, I thought the shock mount was in-board of the top hub mount?.. I forget as I try and avoid looking at the cars Lol

Think we were at cross purposes Lee but as Martin says ...own risk and for race purposes is the usual get-out for these things .It's std practice .

Hub mount would have the camber bolt and shock mount is a couple of inches back using the same size bolt .
The one that came in fecked was a bit scary .The actual pivot arm itself had sheared Good job it went just backing out of the garage and not at 70 clicks .

shim dim

innit

[mettersl]

Thanks for the shim diagram lee, as you say they are easy to make. They came in 0.5, 1 and 2 mm thickness if I remember rightly.

On the camber... I'm still nervous about the offset pin approach in this type of suspension.
The bolt may not be the shock mount but it transmits the loading from the spring/shocker to the suspension itself.
Having had a quick look at Camskill this morning the offset pins are designed for use on McPherson strut systems to change the angles, but the loading is taken somewhere else. The offset bolt is one of a pair and the pivoting takes places around the second bolt. They are also quite short (the offset part) so I think we would need to get custom items made for the application.
Personally I'd also be wary about using one as the sole attachment and pivot as:-
1)There is no rotational lock except by friction and as the weight of the car is on the bolt it will tend to rotate the offset bolt (this is caused by the offset so wont happen on a STD set up). The suspension movement will add to this so I don't believe rotation could be prevented so you'll likely get the adjustment varying over time.
2) The point that Lee made about reduced cross sectional area will reduce the maximum shear stress that this bolt could take. The materials used may compensate for this so I'm probably wrong on this point.
I'm also not sure if there is enough adjustment available without doing some measurement and calculation.

Sorry to be so negative about this but we don't want any unnecessary accidents....

Cheers
Lee

Ok it seems there isn't a lot of point in pursuing the eccentric pins due to possible failure as the consequences are serious. I think I'll slot my upper links and see how close I get to ideal.

Trevor.

I think this is the best option .Once set it can be welded and done with .The only real reason for doing it with pins is the DIY option becomes easier but I think the risks are too great ...for both parties
I have half a dozen sets of top arms that I can slot and set but this needs to be done here .,