Strut bar? In tension, compression, or both
 

I have read many threads over the years and really think it probably doesn't matter. However, the thought came up today as I was bolting a strut bar into the front of my 930.
Anyone care to provide some data, or logic based argument on this topic?
Thanks
David
Performance EngiNerding

A strut bar bolted on to a stationary vehicle at rest .... is in neither. Unless you tighten up the bar and preload it.... I would not put a preload on the bar. A strut tower bar can be under tension OR compression depending on the environment that the car is operated in.

I am installing 2 bars. One steel that is not adjustable, one lightweight aluminum that is adjustable. I planned on bolting the steel one on first, then the aluminum. I can tighten the aluminum one a bit to put the steel bar in compression.
Performance EngiNerding

On my '71 the first bar I installed I put under stress, literally jacking my fenders apart, in order to achieve zero camber on my lowered street car.

Later, when I began autocrossing, I replaced that bar with one that I could put tension on. I pulled the fenders together in order to get MORE negative camber.

Keep in mind that the chassis on the '71 was MUCH more flexible than the newer cars, especially the 930s I would guess.

Bottom line is you need to ask yourself why you are installing a strut brace. On a track car with wide sticky tires it may help some.

I am building the car to play / experiment with. My brother is the race driver in the family, I may take it to a DE event, have no.plans for racing. But any bolt on device that can make the chassis stiffer is worth trying.