Axles Street vs Race

[nicka]

Yesterday, I was removing axles from an 8 3/4 5 x 4 1/2  '71 Barracuda for inspection.  The axles are 30 spline. The car has seen action at the drag strip by previous owners.  I was wondering how I can tell if these are race or street axles?  I'm guessing the material is different?  Would the sound of tapping the axle help?

[Burdar]

I'm not an expert but those look factory to me.  The reason I say that is because after the splines, the axle tapers down.(the axle isn't the same thickness all the way through)  The aftermarket axles I've seen don't taper down anywhere.

That being said, your axle splines look fine.  I've read where some racers use them until there is a noticeable twist in them. 

[Chryco Psycho]

Those are stock for sure , they look fine tho .  The aftermarket axles have a different center & usually have threaded wheel studs instead of drive in splined studs .
On the first pass in my Duster & twisted the axles almost a 1/4 turn , I am surprised they held up to get me home ! The real question is how far did they twist if they retained the 20% twist !!
Fortunately or not the spider gear set let go before the axles did , I still made it home ! When I pulled the center section to repair the spider gears I found the twisted axles which were fine the week before !! New Mark Williams axles were ordered that week which is when I learned about green brgs which I have not used since  !
I truly found the limits of the 8 3/4 , I decimated 5 sure grips , twisted axles & crushed gearsets , I should have just built a Dana it would have been cheaper than repairing the 8 3/4 but you keep thinking just a few more $$ to repair it & after spending $600 on axles why throw them away ?