Driving Impressions: Lower Stress Bar

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Originally Posted by Lil bastard

Is there any data supporting the addition of the side bars? I can see the necessity of the lower stress bar side-to-side (Camber), but there is already significant bracing against fore/aft (Caster) movement.

I've dismantled the rear suspension when I did my tranny work and personally, these side bars appear to be overkill in all but the most extreme track use (I do not incl. Auto-X or DEs).

I have the Mantisport 'Ernie' bar and noticed improvement (not extreme or significant, but definitely improved), + Fr/Rr. Strut Tower braces.

Can someone show me some data that this area requires additional bracing, because I'm not convinced that the side bars are a necessity, or even a positive addition. There's no benefit to over-strengthening something which is already strong enough to do the job.

it is my opinion (as an engineer) that the side bars are not necessary. anti-squat is adequately addressed by the diagonal links. longitudinal flex at that portion of the subframe is tensile and is adequately addressed by the shear plate.

the reason the cross brace (ernie bar) is so helpful is because there are compressive forces between the left and right halves of the subframe that a shear plate cannot resist. because of this, the distance between the lower control arms was actually dynamic under hard cornering loads. the stress bar hard locates the lower control arms (and in turn, camber), picking up where the shear plate leaves off.