For those of you that have installed SFC'S, how important is it to preload the connectors prior to welding them? IE: having the full vehicle weight on the suspention.

I only ask because to me that would make sence, but on "Horse Power" this weekend, they installed a set while the car was on a frame hoist.

Let me know.

Dave

 

SFC stop body flex, and have little to nothing to do with the actual suspension of the car. The suspension that gives while the car is on a hoist is the shocks, springs, swaybars, and anything attached to the axle.

Also, when I say little to nothing to do with actual suspension, I mean stock, working suspension. We all know it stops body flex.

 

There's alot of misconception about this.

"Preload" isn't neccessary. Forget about that entirely.

Think about what you're actually DOING to your car, when you install those. You're WELDING ON something to the car, that will hold the car in whatever shape and orientation it happens to be in while it's WELDED, right?

So what do you get if your car is twisted or bent or something? Right.... a permanently twisted or bent chassis. You just "locked in" whatever misalignment the car had at the instant you welded it together.

You want the car STRAIGHT, with no strange or unusual stresses on it. So for example, you know how when you jack up the car from the front by putting the jack under the crossmember and put jack stands under it behind the front wheel wells, and then let the jack down, you can see the car warp into a whole new shape, with the nose hanging down.... you don't want that.

I had mine put on in a race car chassis shop, on their chassis jig. The car was STRAIGHT. Still is, 15 years later.

 

Well, that was a very clear and definative answer, thank you. I agree and I will do the same.

Thanks,

Dave

 

Old post, but great answer...Thanks..