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I know that aluminum strut bars are lighter but heard rumors that they are prone to cracking under a lot of stress. I'm re-thinking buying Carbing aluminum strut tower braces and going with TRD for just this reason.

Can the experts weigh in on this? Thanks!
 

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i've never heard/seen of a strut tower bar breaking. steel is a bit extreme. honestly i think you're worrying too much :p
 

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lDeeZ lNuTz said:
i've never heard/seen of a strut tower bar breaking. steel is a bit extreme. honestly i think you're worrying too much :p
I second that motion. The kinds of tension you would need to break the strut tower bar would be doing plenty of other terrible things to your car... not to mention your tires would probably have lost grip and sent you spinning into a landfill (if you should happen to be near one ;) )
 

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Yeah I think the stock one looks like a pretty weak design, but is made of steel. How do I know this? I buffed all the black paint one night and put it back on. The next day I washed the car and the day after that I opened the engine lid and found that about 1/5 of it was covered in rust... So I buffed all that off and ceramic painted it silver, like alot of my stuff is now. But anyways, I agree that any forces on your car strong enough break the strut tower would 1: probably snap the wheels off your hubs if your tires could actually grip enough, 2: sheer all your frame and sub-frame bolts off, and 3: mean that you are probably in a wreck or about to die...
 

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I think what he's talking about is fatigue. Yes, aluminum does fatigue much more readily that steel.

I doubt the weight savings is seriously that freaking much. I would go with the steel and paint it so it doesn't rust, like our body panels.
 

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flyboy said:
I think what he's talking about is fatigue. Yes, aluminum does fatigue much more readily that steel.

I doubt the weight savings is seriously that freaking much. I would go with the steel and paint it so it doesn't rust, like our body panels.
rust destroys metal. aluminum does not rust. i'm no engineer at making these things but once metal is bent it's never the same, but i doubt even an enthusiastic driver would be able to drive it hard enough to the point where it flexes the strut bar.
 

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aluminum does rust, and sometimes faster than steel.
Aluminum also becomes stressed much faster than steel.
I make steel bars that weigh very slightly more than an aluminum bar. For aluminum to do the same as steel and last it must be much thicker and as a result may weigh just as much or very close to it.
The high and tight MK1 bar is a huge CNC'ed bar for the mark 1. very bling bling and cool looking. Does the job well. But the RSm bar made from 1" steel is lighter and works much better with slicks. I can lift the car with the RSm bar, but I would never try that with the H&T bar as it will bend and distort the bar and most probably the strut towers.
Now for cars that are show and never really see any streeses, or cars that have lots of wax then aluminum will do you fine. But for actual racing I would stick with steel or at least a structual grade aluminum or Titanium.
Look at it like this... Aluminum bikes are awesome at absorbing awesome stresses. But don't last as long as chromemoly bikes. Chrome moly bikes will jar the hell out of you on rocky sections. Aluminum wont. The idea of the strut bars is to keep the struts where they are at. aluminum wont do that as well for any length of time compared to ti or steel
 

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wait a second then why are all those people who are making engine lid shrouds using aluminum and advertising them as non rusting parts?

i was given the impression that the benefit of using aluminum over steel on certain parts is that it won't rust...
 

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lDeeZ lNuTz said:
rust destroys metal. aluminum does not rust. i'm no engineer at making these things but once metal is bent it's never the same, but i doubt even an enthusiastic driver would be able to drive it hard enough to the point where it flexes the strut bar.
wanna bet?
You are driving a car coming up on 15 years old. it is held together by little spot welds. nothing more. though these are strong they will start to fatigue after just a few years. All pure race cars are seam welded to increase stiffness. Most, if not all of you have not done that. so you have a chassis that can be twisted and turned all over the place. have a T-Top??? feel sorry for you GI. Those little aluminum show bars you throw over your engine are not going to do much for too long. You can put 200 TuRD stickers all over it, it is still going to fatigue
 

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because they are probably coated aluminum.

you can buy aluminum in many different varieties.

Go to a junk yard and look at an aluminum manifold that has sat out in the eliments. Notice that white stuff? That is rust.
Use stainless steel hardware, uncoated on aluminum and see what happens in very short time. I have this 4.6 liters of aluminum sitting in the middle of one of my MR2s. I can show you many many many pictures of coroding aluminum
 

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lDeeZ lNuTz said:
wait a second then why are all those people who are making engine lid shrouds using aluminum and advertising them as non rusting parts?

i was given the impression that the benefit of using aluminum over steel on certain parts is that it won't rust...
Rust = oxidation. Steel oxidizes to form a brown substance. Aluminum oxidizes to form a white substance.
 

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did a quick search: http://www.usmotors.com/products/ProFacts/modernaluminum.htm

Clean metallic surfaces exposed to air quickly acquire a film of oxide, which, at ordinary temperature, is thin and invisible. At higher temperatures it is thick enough to give well known characteristic colors - rust. The nature and properties of the film depend upon the composition of the metal itself and its environment. Aluminum and stainless steel, for instance, owe their high durability to the formation of a continuous and permanent file that is stable under most conditions of exposure". In general terms, aluminum is more resistant to corrosion by most common materials and atmospheres than cast iron, and far more resistant to corrosion than is carbon steel.
i'm not arguing that steel isn't a more rigid material, but steel corrodes faster than aluminum in a normal environment. seems like basic stuff but i was like 99% sure on this. i just think a steel strut tower bar isn't necessary....the trd bar is very nice though :p
 

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I learned this about aluminum the hardway. I purchased my Shelby Charger GLHS new in 1987. I replaced a lot of the bolts with aluminum and Ti. I moved to Suffolk england. My home was 300 yards from the Northsea. within 6 months stuff was falling off the damn car. Stuff that held on great when I was living in Phoenix

Finally, from the small island of Roatan, comes this dispatch:
http://www.roatanet.com/insights/news_june.htm
"Anything ferrous exposed to saltwater or salt atmosphere will
deteriorate very quickly. Saltwater will also have a deleterious
effect on non-ferrous metals like aluminum. They are subject to
corrosion and eventually become brittle. Aluminum cans thrown into
saltwater will completely dissolve in a very short time. Zinc-coated
(galvanized) surfaces will eventually yield to corrosive elements if
not properly maintained.

If you intent to install a metal roof on your home then I recommend
the alloy coated products similar to Gal-va-lume or the factory baked
enamel coated metal roofs that are also back primed. Be sure that any
field cut edges of metal roofing are re-coated with rust inhibitors."

Finally, the Navy report entitled Corrosion Prevention and Detection
(http://www.abm.rda.hq.navy.mil/CorrosionBook2a3.PDF) has a listing of
organizations working on corrosion issues toward the back. Even if
you're not interested in the highly technical information in the
front, this "webliography" can lead you to organizations who can
provide information on guarding against such corrosion.
 

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I don't think the difference in fatigue life between aluminum and steel will really matter based on the kinds of stress loads that come from strut tower braces. Just paint or powdercoat them either way and don't worry about oxidation.
 
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