superwhitetc89

has anyone seen a strut bar that goes across the floor in the backseat?

rosedaleny806

there actually is one, I saw it on ebay but it looks weird lol, and there's also the one that goe in the trunk area.

superwhitetc89

has anyone ever bought this part and used it?

AcidDrop

iTrader: (4)

you mean behind the front seats, yes i have seen it on ebay but not in person. not sure if it will even stiffen up the car at all, but they do sell 4 different type of rear strut bars though.

milanshere

dme makes a rear strut bar if thats what you talking about. i have one .
aciddrop i think you are talking about a harness bar??

AcidDrop

iTrader: (4)

DME, Greddy, Ingalls, and MonsterMotorWorks make rear strut bars.

Edit: it's called a cross floor strut bar.

Jlowe

http://cgi.ebay.com/ebaymotors/ADJUS...Q5fAccessories

I think thats what hes talking about. I wouldn't get it, I don't really see how it would do anything but be annoying.

senseiturtle

Just my opinion, you may want to consider reinforcing something outside of the safety cage first. Strut tower bars, bushings, suspension components (sway, spring, shock), etc are all much more immediately noticeable and effective.

If you're at the point where you need chassis stiffening INSIDE the passenger cabin, then you're racing seriously enough to need a full welded-in roll cage.

blackcherry07

i agree on all but the bold....our strut towers are so close to the firewalll that it offers our stiffening....

senseiturtle

I've posted a thread about the dynamics of a strut tower bar, and they're much more effective than many give them credit for. Of course, on that technical discussion thread, few read it, and even fewer replied.

The gist of the argument is simply that if you consider the lateral forces imposed by a cornering car at the tire, that this force applies a torque against the 3 bolts at the top of the suspension unit, with a value which can reach 3,000+ ft-lbs during a heavy static turn. The impulse forces sustained during potholes are even greater. With this in mind, draw out a force diagram, and it's very simple to see that a FSTB will go a long way in resisting positive camber gain. I would be happy to link articles if you still don't believe me.

It's also interesting to me that people are pushing the Ingalls rear strut braces, which claim to do the same thing, but do so RIGHT ON TOP of the MASSIVE section of rear frame. See, those suspension bolts are directly incorporated into the frame... and that bar runs about 1.5 inches directly above it across the cross-section of the car.

In the front, the suspension bolts are NOT incorporated into the frame, to the same degree. It's about 4 inches from the firewall. In addition, it's arguably more important than the rear in terms of maintaining camber through the turn, since you're relying on those front tires to do ALL of the turning, and ALL of the accelerating.


I got my front strut tower bar as a last piece to my STS puzzle, just sort of as an afterthought. I immediately gained a lot of respect for it. In fact, it's managed to calm down my rear rend, which gets really loose at the end of a fast slalom... i tend to exit those semi-sideways, just from the continual loss of composure throwing it side-to-side.

blackcherry07

ok...well i cant ignore your proven research at all and i stand corrected....but now i ask....would it not be better to use a triangulated bar?? if what you are saying is that the strut tower is far enough from the firewall to need to be re-inforced then we should use a triangulated bar not just a cross bar...

also shoot me a link to your thread i would love to read it....i must have missed it...

SW_08

senseiturtle

Would it be? Well, perhaps, but it's hard to say. Most of the benefit of the strut bars comes from the welds between the contact plate and the tubes.... this is what resists camber addition. The secondary benefit comes from preventing compression/expansion, which helps with the frame twist. Adding a triangulated bar would only affect this "secondary" benefit... but i certainly don't see anything wrong with it.

https://www.scionlife.com/forums/viewtopic.php?t=245938

or can be searched as the only result for "rethinking strut"


I don't want to give the impression that it's the "end-all, be-all" modification... and certain manufacturers of poorly-welded, or not-even-welded models are certainly lacking any and all benefit from a suspension standpoint (bling only).... but a well-constructed unit DOES have some merit, and I don't regret it on my car.

The only mod I truly regret, is the header, which I got annoyed with and gave away. Also put me in SM... but that's another story.

blackcherry07

well i have a friend who is a spectacular welder so ill get with him and see if me and him can come up with some type of triangulated bar...

highvoltage1

iTrader: (11)

Ok sensaiturtle so on installing a FSTB is it best to jack up the vehicle to install or leave on the ground, or one side at a time?

O4COBRA

I've always noticed a big improvement from a rear bar. But with the tC I don't see the need. The way the struts mount to the floor there is already a bar like structure there, that the upper mounts straddle.

senseiturtle

The instructions state to install the bar with no weight on the wheels. So, that's the way I did it. In the end, I'm not sure if it really matters or not.

highvoltage1

iTrader: (11)

Thats what i always thought but wanted to see your opinion since you made a good write-up.