Does anyone make a rear strut tower brace for FB's?

Thanks!

-Jacob

 

No, and with good reason. The spring towers on the FB are so short, the parcel shelf floorpan connects them only inches from the top, rendering a rear strut tower brace pointless for street application. However, if you drive the car in rally racing and upgrade the rear, then you may see some benefit

 

What is you just WANT one........because you feel the car is weak?

Mine seems to flex like there is no tomorrow.

I even noticed as I tried to jack the car up at the standard jack point that the metal BENT rather than lifted the car as it should.

Everything I CAN bolt to sturdy it up......I want to bolt in.

 

Don't jack it there - use a floor jack under the frame rail, with a flat thin piece of wood to prevent the floor jack from marking up / bending the frame rail. You should only use that weak jackpoint for emergencies.

 

I made my own rear strut bar out of stainless steel.
big difference, my moonroof doesn't rattle now. your right, the car does flex.

 

where would u recommend jacking up the front of the car without anything from the floor bending? i use the rear pumpkin to jack the rear up... yeah so front?

 

I just wrote it out 2 posts ago

Jack from the frame rail with a piece of wood to distribute the pressure - front or back!

 

engine cross member

 

That's what I use, crossmember in the front, the center of the diff. in the rear.

 

But if you use the crossmember, be REALLY careful the entire jack is on the crossmember. If like 3/4 of it is on, the rest can be causeing problems with youre oil pan. Ask me how I know...Luckily the oil pan was on the bad engine. From the front it looked ok, but from the side it was obviously off. Just double check before you put weight on it, and put a block of wood or something under there also just to be sure and help spread the weight .

~T.J.

 

Manntis - thanks for the reply. The reason I asked is because I just finished installing one in another car and was very suprised at how effective it proved to be in "stiffening" up the car - despite how stupid I thought it was before the install!

For most imports (cough, rice, cough) there are dozens of different STB's available - I was just hoping to see if it was the same for our beloved FB's...guess not.

If I ever get bored, maybe I'll make one up and try it, but it looks like it's not really needed. Thanks!

 

Hey sterling7 any chance of some pics??

I'm thinking of doing one too cos if i give the car a real thrashing sometimes the hatch will not open 1st time cos everything has moved

 

there are a few STBs available for the FB, if it's FRONT STB you want. The engine bay has virtually no support for the strut towers save the two forward frame members, tied together at the bottom by the crossmember, so an STB makes sense. But as I've said, the rear strut towers are already tied together within inches of the tops by the parcel shelf

 

been there, done that it all blends in, in low light.

 

yeah, i've got to find'em

 

Seems to me that a rear tower brace wouldn't be a good idea with upgraded suspension. We rant and rave about the fact that running a stiff rear is not desirable (ie ditch the aftermarket sway bar in favor of the stocker, or none at all) and everyone is recommended against poly bushings in the rear. I know from personal experience that with a stiff rear end (had tight suspension and a phatty sway bar back there) the car jumps and slides all over the road. Fun, but not fast. I'd say that it is much more important to make the front rock solid and the back only marginally stiff. Then turn your checkbook towards rim/tire, drivetrain, engine, or something else.

In short, I wouldn't bother.

 

I agree,, to a point. i spray wd-40 on the rear bushings every once in a while to keep'em soft, with the stock sway bar. adding a support up top, does make a differance while keeping the rear as it is. it's one thing that once you drive it, you'll say, **** it does work good.
for cars without sun/moon roofs maybe no need for it.
remember,,it's a uni-body design. IMO

 

Redwood - I have to disagree with ya on this one. Stiffening up the car has no ill effects IMO.

You ever seen a road racer NOT install a cage because he likes the rear sloppy? The point is to make the chassis as firm as possible so that the suspension can do it's job, then adjust the suspension to do what you want. Then you can take off the rear sway bar, adjust the spring rates, tire pressure, etc. so that the car handles how you prefer. If the car is all loose, the chassis itself will be absorbing way too much stress - no bueno.

That being said, I think I agree with Manntis - upon inspection, the design of the rear shock towers seems to be very strong, and not need extra bracing. I'll do some messing around on my own car this year to test different stuff, but I think in the end, an Autopower spec7 cage is my ultimate goal...

EDIT: from your sig, looks like you are working on a FSAE car? What school? I miss FSAE.... sleeping is overrated!

 

Good points.

In this case, I'd say no still. Since this isn't a road race car (at least, I think it's a street car), there likely isn't a budget to do everything, then get rid of what's not needed. When I was running a really stiff rear end on the street, I couldn't accelerate out of corners anywhere near the limit since any small contour in the road (and we all know there's a lot of those) would send one (and consequently both since it's a solid rear axle) tire out of contact with the road. (I'd also like to point out the mis-education out there about tower braces that originates from all the ricers out there. Many, more than makes me happy, think that this is a good first suspension upgrade whereas this makes minimal difference without a beefed up strut/spring combo and some decent rubber. Just a side note)

Manntis' reasoning seems like solid thought too, and I would definitely agree with him. But here, I'd say that a little chassis flex may not be that bad if it comes with more tire contact.

Now, if we're talking about road racing or auto-x, get as much aluminum bracing as you can in that rear and then assess your position.

Yes indeed. I'm on the University of Washington team. We just finished our first assembly/disassembly (almost on par with Cornell). I also just got up after working until about 8 this morning (slept in our machine shop ). Sleep is for the weak.

 

Ahhh, I will always look fondly back on my year in FSAE - I helped out with UTSA's all aluminum car (F4i motor). Fun stuff. Never drank so much Mountain Dew in my life...there were usually only 5 or 6 of us working on the car, and we literally lived in the shop for a few months with only a few hours of sleep a day...

I agree with you that STB's should not be considered the wonderful mod that they are. Fact is, most "ricers" (ugh, my gf included, before I met her) can buy them at Pep Boy's, bolt them on in their garage with a crescent wrench and pliers, and show them off at cruise nights, with minimal hassle. Try doing that with a spring/shock/sway bar combo in 15 minutes. It's the same kind of logic that makes ignition wires and cone filters the end-all be-all engine mods to the umm....technically challenged.

I was just trying to point out that IMO, STB's should NOT be considered suspension mods at all - they are chassis stiffening braces that let the suspension do it's work properly. In my Mustang days, I was amazed at how a set of welded subframe connectors would literally make the car feel like a whole new beast, and they were cheap (My 92 GT sported a set of custom fabricated welded subframe connectors for a little over 100 bucks).

Fortunately, I'm finding out that Mazda designed the FB's to be pretty darn stiff on their own, and they apparently don't really need extra bracing in the rear on a daily driver.

Whew, after all that - time to warm up outside so I can go yank my stock rear sway bar. I do agree with you that the rear needs to be a little looser on these cars for optimum handling, if not fun.

Good luck in the FSAE competition!

 

I see what you mean now. I was treating the STB as a suspension component, but I think that you may be right in thinking of it simply as a part of the chassis. Good call on your part and I agree with you. (But I still wouldn't put on on the rear towers of my FB!)

 

Yeah i'm definitely making one for the front... but i want one for the back too cos IMO it is needed. This is based on my experiences with the body moving after a good thrash...

So no ones got any pics of a rear one?

 

With people asking for pics of a rear strut tower brace...

I have to ask........are these actually made? Or, if someone has one.......would it have to be custom?

 

I'm almost positive there isn't a production one out there. I bet there's only a handful of custom ones out there too as I've never even seen one (and I've seen a decent number of first gens).

 

I know this thread is super old now, but I thought I would post up this pic of a rear Brace for the FB. I think it looks amazing and would serve a purpose in strengthening the rear. Not sure who makes this or if it's fabricated. I asked the seller of the car to try and determine the make. Anyways, here ya go..

Update:

re amemiya apparently makes these braces but I can't find them anywhere.. Maybe it's an old product.