Proper intallation and function of strut tower bars [Merged 1-7]

[Tsi_User]

pro car parts has some pretty cheap ones for sale:
http://www.procarparts.com/store-list2.asp?makerID=24&modelID=132&year=1997&cat=5&sub=43
hope this helps

 

[speedracer91]

i know its a dumb question but, i want to know how to install my front strut bar.
i THINK that i just un-bolt the bolts on top of the strut tower (around the strut) and put the bar on and put to bolts back...is that right? thanks in advance

 

[Gary 420A RS]

answered your own question....

 

[speedracer91]

swwet thanks to you and.. uhh me..

 

[Seattle GST]

by the way, if you jack the car up where most of the weight is off the front tires, THEN install the bar nice and tight, then lower the car, it has been shown to provide a little more stifness as the top of the "box" will be more of a true square, rather than the loaded shock towers that have the vehicle weight on them.

 

[Defiant]

^ ^ ^ And, some say to intall them under tension instead of pressure. So it probably doesn't matter so long as it's not rattling.

 

[98FWDSM]

ok, i installed a front upper and rear upper strut bar (have a rear lower but havent installed it yet) and my car feels really really tight...i know that that is the reason for these bars but the megan racing bars that i have have a nut that "pre-stiffens" them so they are already very tight against the towers....now, this may be a very stupid post but i just wanted to make sure that i am not making my car handle worse or anything. . .

Thanks

 

[GSsilentT]

The only problem of over tightening the nut on the strut is the risk of stripping the nut. Having the nut too tight will not effect ride quality. Just make sure you tighten to snug and not to strip.

 

[mitsuclipsegsx]

and make sure it doesn't make ur car go up in flames

 

[igs]

The purpose of a strut bar is to share the load between the two strut towers. How tight the nuts are have no effect as long as it's so loose that it moves.

 

[truwarrior]

Found this at http://www.tanabe-usa.com/strutbars/


Adjustable Preload

A very common error when installing tower bars, It is always recommended to raise the vehicle when installing so that the load of the shock uppermounts on the shock towers is relieved and balanced out. When raised, and the tower bar is placed onto the vehicle, the preload can be adjusted and set. After it is bolted on and the car is lowered, each shock tower will have equal load and will prevent independent movements of each shock. This will provide an extremely noticeable difference after installing. If a tower bar is installed on a car that is not raised, great benefits will be missed.


Anyone notice a difference doing it both ways? Level and then jacking the car up to install the strut bar?

 

[definitiveno]

Can that be right? i thought the bars were supposed to pull on the towers, not push......

 

[rowlex]

from what i hear they are suppose to be neutral.

 

[truwarrior]

The only way I can see it being neutral when installing the bar on the ground is is both sides of the car weighted the exact same. I don't know though, I'm just getting into this suspension stuff. Then again I had my car on stands the other day and I had to lower the car inorder to get the swaybar back on...does that sound right?

 

[Defiant]

If you'd searched, you may have found that this "breakthrough" came through the forums about 18 months ago.

I'm not convinced strut bars matter, but many are. So I'm not the one to ask which way matters more.

But I suppose people willing to pay Tanabe's prices for $6 worth of bar are soothed by the bedtime stories.

 

[herostar]

I've never heard of this before, but I'll give it a try and see what happens. I've only got a front bar though.

 

[kyle h.]

this has been the correct way to install strut bars since the day they were invented.

 

[truwarrior]

I don't think it's this way in the vfaq

 

[leet]

As Defiant stated, old news.

Why would you want them pulling? They are there to square off the structure (for more rigidity).

 

[jtmcinder]

First understand what the parts can do. Then decide what you want them to do and install them such that they do what you want.

No, don't say, "yeah, whatever." Go back and read that again.

Some people want STBs to keep the unibody the way it is in the resting state. So they jack up the car to eliminate stress before they install them and they don't include a pre-load.

Some people want STBs to help them to have the most negative camber while cornering that they can get (legally). So they install them with the car on the ground (since this usually pushes the towers inwards a bit) and pre-load them with as much tension as they can.

Again: first understand what they can do. Then install them in whatever way will help you the most.

Yeah, whatever.

- Jtoby

 

[slugsgomoo]

jtmcinder is right. Negative camber can be slightly increased by installing with the car on the ground. If you look at the way the car stresses in a corner, without a STB you are getting \__/ instead of |__|, or at the very best |__/ (not that extreme, but such are the limits of text).

With a sturt tower bar, neutral should give you |__| and weighted should give you a bit of /__\ for your negative camber. I can't imagine why you would want to push the tires further apart for positive camber, unless you need a quicker turn in. Frankly i'm running a wide (235) tire and the turn in is plenty snappy, without any positive camber.

Of course, install them for what you need. If you're not canyon carving, or better yet tracking the car, it probably doesn't matter either way. For mild stuff, go neutral. If you want to get the most out of them, weight it some, get that touch of negative camber, and rejoice.

work's for me.

 

[bjones18]

Adjustable Preload

A very common error when installing tower bars, It is always recommended ........installed on a car that is not raised, great benefits will be missed.

Anyone notice a difference doing it both ways? Level and then jacking the car up to install the strut bar?[/QUOTE]

Another common mistake is buying and bolting on parts cause someone makes them and "they should work...right?"

1G struts, and 2G SLA suspensions would not have the same effect from a strut bar. The flimsy sheet metal bolt on brackets are the "soft" link in the chain. THEY SHOULD BE CASTINGS for stiffness! ($$$ it is much cheaper to bend some sheet metal).

The 1G strut top, and 2G upper control arm are in tension on the outside wheel during cornering... therefore, if you put the strut bar in compression, it will pass through zero as it is loaded during cornering

The highest lateral loads are taken in the lower control arms (compressive). A nice straight bar connecting the subframe side to side would offer the most benefit for structural stiffness. Unfortunatley ( or fortunatley) my 2g has a 3" exhaust and drive shaft which makes this difficult.

 

[truwarrior]

Hm so for a FWD car that just wants to go straight, it's probably best for the most cases, to leave the strut bar neutral and install the strut bar with the car on the ground? Thinking about weight shift here and how it affect fwd camber/grip. Thanks for the input.

 

[jtmcinder]

The highest lateral loads are taken in the lower control arms (compressive). A nice straight bar connecting the subframe side to side would offer the most benefit for structural stiffness. Unfortunatley ( or fortunatley) my 2g has a 3" exhaust and drive shaft which makes this difficult.

I have no idea why you would bring up the drive shaft, but the lower front brace from RRE has no problem clearing the 2.5-3" downpipe that RRE also sells.

I agree that this part is at least as important as the upper brace.

- Jtoby

 

[bjones18]

I have no idea why you would bring up the drive shaft, but the lower front brace from RRE has no problem clearing the 2.5-3" downpipe that RRE also sells.

I agree that this part is at least as important as the upper brace.

- Jtoby

In reality stiffness is difficult to acheive. Between the lower control arms 30,000-50,000 N/mm is what you want. And this is VERY difficult to achieve with bolted members. A 1" tube, bent to get around exaust with squished ends bolted in single shear at each lower control arm will be lucky to provide 5,000 N/mm.