Thread: 1302
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Old December 9th 2010, 17:28
1302 S 1302 S is offline
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Join Date: Dec 2010
Location: Sweden
Posts: 6
Hi, Clive
Many questions you got. Realy nice to get responce and share thoughts.

Coilovers are homemade. Lower mount from 944T. Thinn wall pipe and threaded end from a 944N/A. Shockabsorber is golf inserts. The spring and threaded sleeve is bought separately.

As I wrote the TCA rebuild is only a part of a larger plan. I will build new towers for a adjusdtebly pillowball top mount. Adjust the basic angles, so they better fits a lowered car. To be able to increse caster. The top mounts will include supports for a brace bar.

I will also look at the inner mountings for the TCA. They looks very weak and mounting point is not adjustebly.
Droping the inner pivot on the TCA is not a good idea. Dropping it would cause the angle between TCA and strut to increse.
On MacPherson strut-equipped cars, the wheel will gain negative camber under roll as long as the lower control arm is positioned
less than 90 degrees relative to the strut axis. Beyond 90 degrees, the suspension will gain positive camber instead of negative
as it compresses, significantly compromising grip.

I see that you and I have different oppinion about weight transfer. In my experience and what a learnt, I try to minimise the weight transfer.
I try to place parts as low as possible and they should be as light as possible, all to reduce the influence of the torque arm (both lenght and strenght) that that virtally apperes between the gravity of center of the car and roll center when the car turns. I also have increased the tracktion-width to decrease the weighttransfer (the main reason I choosed P-parts for chassie). This make the suspension work in a smaler range and the weaknesses of the MacPherson design could be less.
To adjust the couplung between front axis and rear axis I will rake the car in different degree.

Rear suspension. The rear end bushings will be replaced with the parts you see. Its practically the same change Wally made but I have constructed the kit myself. I hade to make a outer plate to hold the bushing in place. I hope that the bushings and balljoint will decrease the friction and give better response.
I would nerver use alu arms in a full coilover solution. The reason is that the alu arm isnt made for it and you change the stress points in the chassie.
First all the rear weight of the car from the torosionbar (spring) via springplate mount is moved to the to the lower coilover mounting point.
Now the lower point of shockabsorber mounting, has to deal with both the force from damping forces and the weight of the rear end
of the car. The lower mount is single sided and the increased load will sooner or later breake it due to overload and/or fatigue. In the upper
end of the shock the unsupported mounting have to take all the added force. On 911 p-cars they brace and reinforce the upper mounting points to avoid cracks and deflection.
If I do a coilover mount I should mount the steel arms (compare the lower mounting points, both sides) and connect the upper mountings to a
to a multi point brace or even better rollcage.
In my case I will see how far I could take the "standard solution" due to make it more exact and smother and it will be combined a 5 point brace.

I probably end up with a full roll cage. Its true as you said that it will improve the handling the chassie could never be too stiff.

//Anders
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