912 outlaw project

[911hillclimber]

I too made my own just as the rose jointed version above in 1990!
TBH I doubt it made much difference.
Without triangulation I see little benefit. The method where a solid tube is welded in solid will add more than a jointed one.

A good geo set-up and corner weighting is far more beneficial.

Those of you who know Shelsley Walsh hillclimb will know this entry bend well, 'Bottom Esse' and the direction change and braking and adverse camber, but no roll, flat, and very stable, about 70 mph.

Minor and effective mods guided by Bob Watson over a 15 year period.
You should see Jonathan Williamson's entry to this one! Just brilliant.

[Gary71]

Clearly the picture I posted is overkill for a road car on normal tyres. Just one triangulation from the top of one tower to the bottom of the other would do most of the job.

[haasad]

Gary, that's exactly what I built for my car, it won't resist twist though due to the rose joints, it does however make the strut towers resist "parallel" forces.

Andy

[jury]

Gary, that's exactly what I built for my car, it won't resist twist though due to the rose joints, it does however make the strut towers resist "parallel" forces.

Andy

Some great info here chaps...

Needless to say:

Mk2 is in progress

Mk 3 is a piece of scaffold


Cheers
Chris

[KS]

Maybe all you need to do is use packing pieces either side of the Rose-joint to prevent its twisting action, but take advantage of the ability to use left- and right-hand threads to put the shock turrets under tension. I don't think anyone ever installed a regular strut brace to do anything other than restrict the flexing of the turrets in and out under load. Triangulating the whole front end is a different solution to a different problem. Maybe.

[Bruce M]

Unless the car is converted to coilovers (RSR, 934, etc).... How much load is realistically applied to the strut tops? The wishbone would take most of the forces, I'd think.

If you don't like the rod ends, you could use a clevis joint.

[Cortina]

Maybe all you need to do is use packing pieces either side of the Rose-joint to prevent its twisting action, but take advantage of the ability to use left- and right-hand threads to put the shock turrets under tension. I don't think anyone ever installed a regular strut brace to do anything other than restrict the flexing of the turrets in and out under load. Triangulating the whole front end is a different solution to a different problem. Maybe.

Why do you want to put stresses into the shock turrets ?

[KS]

To prevent them naturally flexing under load? Adjustability also allows you to take up slack in mounting bolts, etc

Commercially the advantage of 'adjustable' strut braces is that no two cars are exactly the same, especially if they've been repaired at some point, so the adjustability allows one strut to fit all.

[Cortina]

To prevent them naturally flexing under load? Adjustability also allows you to take up slack in mounting bolts, etc

Commercially the advantage of 'adjustable' strut braces is that no two cars are exactly the same, especially if they've been repaired at some point, so the adjustability allows one strut to fit all.

I know all that ... but you did not answer my question ... prompted by your comment " use left- and right-hand threads to put the shock turrets under tension"
I agree with holding them in place ......... that's what I have done , but not using the threads to jack them apart or pull them in .... your use of the word tension is suggesting you want to pull them in ??

[KS]

OK, maybe bad choice of words as it could imply tremendous forces being involved… Nobody's suggestion cranking the turrets in or out using hundreds of pounds of force. In the same way that a welded-in roll cage helps to prevent a shell moving, a 'snug' strut brace will help you prevent the shock turrets from moving. The adjustability simply allows you to make the bar a snugger fit than a one-size-fits-all brace.

[jury]

I could always remove it, if it helps with the debate

[haasad]

No don't do that... whatever it does or doesn't do it looks cool......so by definition must stay. You're a designer aren't you

[911hillclimber]

I think the rose jointed idea (as on my car too) will keep the top mounts in a set dimension, but if you have the rubber top mount bushes still what do you gain really/ The bushes flex like mad in comparison to the shell at that point, braced or not.
I installed spherical bearings in my top mounts at the same time as the strut 'brace'.

There is a diagram in the bible, Anderson's tuning book that shows the forces involved. The load on the top mounts is quite low as there is a 'lever-ratio' from the bottom ball joint to the top mount and the tyre in contact distance to the lower ball joint and the top mount.

at a guess this is about 3:1 or 4:1 so the top mount see's roughly 1/4 of the lateral force in a corner, most of the lateral thrust is straight along the lower wishbone to the w'bone bushes, they too deflecting if rubber.

all this stiffening only pays off if you take all the rubber out of the suspension.

I did this on my 911 and after, my Impreza, nylon and hard grade poly bushes everywhere.
I have since put rubber back into the front of my 911 with polybushes in the anti roll bar pivots.
Bliss.

Lots of added harshness, but no flexing as the car move from left to right et on a hill climb.

[Darren65]

Anything to share Bro?….

[Gary71]

I think we scared him off with talk of BIW modal stiffness...