Installing Strut Bars

[007max]

I have front and rear Cusco strut bars ready to be installed on my s130. I have read a lot of discussion (concerning FWD applications) about whether strut bars should be installed with all four tires planted firmly on level ground or with the car jacked up from the frame with no load on the suspension to "pretension" the bars once the car is lowered. What is the consensus on HybridZ about this?

[auxilary]

doesn't really matter, since gravity pull is the same on all corners.

 

and you only have 2 points of tension, rather than a triangulated setup, so it won't really make a difference as far as frame vs no frame load

[johnc]

What is the consensus on HybridZ about this?

 

Don't believe everything you read on the internet.

 

1. Park the car on a level surface.

2. Disconnect front and rear anti-roll bars.

3. Measure and adjust the ride height making sure the car is level laterally.

4. Install the STBs without any tension or compression.

5. Rinstall the anti-roll bars making sure not to add any preload.

 

Or, like 99.9% of the people who install these, just bolt them on.

[dimsum]

Hmm. I never knew that the instructions were so complex for installing such a simple modification.

[Pop N Wood]

Or, like 99.9% of the people who install these, just bolt them on.

 

..

[buZy]

Ok just them bolt on?

How about preloading some tension into it as well. With car on the ground adjusting the bar length so the towers are being slightly pulled together. Removing as much as possible, fastener, mounting points, or mounting brackets tolerance. For S30 bolt-on bars this tension would create a very insignificant amont of shear on the suspension isolator studs, yet removing almost all the mounting tolerenaces. After bar tension is applied, then tighten all mounting points. So the bar, as much as possible, becomes a stressed member in the car like every other major component in the unibody. To me proper installation is key to creating such a member from a bolt-on item with many intersections of motion.

[JMortensen]

I tension mine up a bit, but I really don't think it makes much of a difference. In the Z they get pushed and pulled on especially with stiff springs, so if there is slop in the bearings, the real solution is to replace the bearings. I doubt that anyone could ever tell that there were slop in the bearings from the driver's seat though...

[cygnusx1]

I tension my rear strut tower bar a little too. The front triangulated one is non adjustable so I mounted it loosely with the car on level and drilled the mounting holes for the firewall brace. It made a really positive difference to the feeling of the front end of the car in steering and mostly in bump absorption. It seems to allow the front suspension to do it's job and not let the unibody flex.

[johnc]

Putting tension or compression into a STB is not a good idea. Without some way of measuring and comparing each side of the car you don't know if one side is moving more then the other and introducing asymetry (assuming there's none to begin with).

 

BTW... tightening an adjsutable STB to about 15 ft. lbs. is not enough to move the strut towers.

[JMortensen]

I always tensioned it by hand, so I doubt i hit the 15 ft lb mark, but I do think they moved, because you could feel the bar tighten up. It was very similar on my bars that went to the firewall. Those would just keep tightening and tightening because the firewall wasn't sturdy enough where I attached my clevises. Regardless, I don't think it really matters on a stock Z with strut bars. The strut towers flex so much anyway that if you distort the strut towers .010" one way or the other I just can't see that tiny change making a real difference to the driver, especially when the strut towers are still flexing all over the place anyway. They do serve a purpose and they do make a HUGE difference, but they aren't going to positively locate the strut towers in relation to the rest of the chassis by any stretch of the imagination.