When I made the F suspension 4 inches wider, we also needed to adjust the Weltmeister roll bar.

We did this by heating it, and rebending it while hot.

To get back the original torsion rate I would like to get it heat-treated again.
The guy doing it needs to know as accurate as possible the material composition.

Weltmeister mentions : aircraft alloy steel but that is not good enough.

Can anybody help me out?

 

i cant believe such an awsome looking car would waste its time with a fasion item like that .
mounting your sway bar above the control arm and linkiing it to the spring pertch doubles its effectivness and reduces the need to mod it for your wid body set up if .
its probably carbon steel like every other sway bar

 

Agree completely, but is not easy to find a way of fitting this .

 

well i cut the standard mounts shorter made extra brakets to trianglate them installed the standard bar upside down put 5/8 rod end over the swaged down end of the bar and an M10 rod end onto the spring perch with a 24mm bar the car nose dives into corners and will under steer from too much front bar if i am going slow or on cold tyres . also have to tuck the power steering hoses up out the way . And let me tell ya it was much easier than making the front contol arms wich I'll do later .
DANG thats a good looking car Hans

 

It maybe better to get custom bars. Tarrett engineering maybe able to do that. Given the effort of the widebody I would be more comfortable doing that than modding the welt bars.

 

Yes, have been lookin into that. Can also be built from standard parts.

Will be done, but will take longer. Was looking for a Q and D solution here.

 

I would guess 4130 because it is a fairly typical steel used for high strength tubing, often described as aerospace alloy. The weltmeister bar is welded isn't it? That would indicate its probably not 4140 or 4340. It's probably not 1018 or anything in that series because that is a basic carbon steel.

You can see 4130 reference as an aerospace alloy here: http://pacificalloys.com/alloysteel.html

Regardless, the hardness will not have a significant affect on the Modulus of Elasticity (Stiffness).
4130 @ RC35: E = 29.7 ksi http://www.matweb.com/search/DataShe...ID=7492&ckck=1
4130 @ RC13: E = 29.7 ksi http://www.matweb.com/search/DataSheet.aspx?MatID=7488
4139 @ RC17: E = 29.7 ksi http://www.matweb.com/search/DataSheet.aspx?MatID=7486

I would say its likely that the bar is in the annealed state as purchased from Weltmeister, but you can verify by asking your guy to do hardness test on a section of the bar that was not heated to be bent.

 

Thx Adrial.

 

I was guessing "mostly round".

Get a sample and send it in for chemical analysis, done deal.

 

Agreed, but does not qualify as "Q and D"