http://cgi.ebay.com/ebaymotors/1982-...QQcmdZViewItem

havent seen titanium before. Im smelling aluminum knockoffs!

 

Man I remember seeing these awhile back but can't remember who made them. I believe that they really are titanium.

 

The way the welding on them looks suggest they're not aluminum.

 

Why sure. They look titanium to me.

Titanium-colored (sort of) spray paint, that is.

Simply printing that nice warm-fuzzy buzzword on the box doesn't have any necessary connection with some chemical element.

 

even if they actually are titanium, why would you want such a high fatigue rated material as a control arm? It couldn't possibly be enough lighter than a moly one to make a noticable difference and IMO moly has too high of fatigue rate.

 

Can you explain that? I've never heard of what "fatigue RATE" is before..? ie. how quickly it fatigues from cyclical usage? I was pretty sure cro-moly is another BCC crystal structure and behaves the same way most other steels do. 'splain Lucy!

 

Ever hear a prostock guy saying he needs new pipe? The car is starting to flex to much and isn't working well. I really don't understand why people pay so much for ex-pro stock cars, they're basically worn out which is why they're being sold. They're ok for lower powered class cars, but you're still buying a chassis that is considered wore out by the team who's giving it up.

moly is a harder material, therefore more brittle. It may/should take the initial impact better, but a second hit may condem it/you. Watch that prostock crash from last season where the guy crosses the track, t-punches the wall, then the other car hits him. When the other car hits it(2nd impact) that side of the car literally decintigrates. - sorry, can't rememebr who it was

NHRA/IHRA are the only sanctioning bodies left that require moly for higher speeds. Other sanctioning bodies require steel for higher speeds for this reason.

 

Right; plus, since CrMo steels are harder and stronger, people typically use thinner tubing to get the same yield strength, which leads to an even steeper end-of-life "cliff" of reliability... it's all good, until it starts to go downhill, and when it does, it's OVER. No gentle slope of retiring into the sunset.

Great for parts with a finite, predictable, known-in-advance lifetime (500 laps, 100 passes, whatever); VERY bad for a street part whose longevity needs to be in the multi 100,000 mile kind of ballpark.

Alot of racing parts are like that. Just being "stronger", and "stand up to the punishment of racing", doesn't always translate to being better for a car that gets used on the street.

 

ah yes, they do work harden and get brittle, but that's only when overloaded past the tensile limit into mild plastic bending. I'd hope you never load it that much, but if you can't control it very well, then who knows.
Point taken.

 

very well said sofa.

Yes, they are able to use a thinner material while still maintaining the require tensile strength. That is why moly is considered lighter. The material itself is the same weight, but since it's tensile strength is higher, they use a thinner material to get an equal strength, thus making it "lighter". - The thinner material just worsens the fatigue.

Like I said, unless you're in a class that's overly demanding(such as pro stock) there's no reason to use moly. In a full tube chassis car a moly is only 100lbs lighter than mild steel. - I'll take the slight extra chassis weight in exchange for a better chance at walking away if the unfortunate should happen.

 

Either way, that would not be a good set of LCAs for a cornering car. Heh.