'97 Z71 Torsion bars

Just a quick one.
Are there any aftermarket torsion bars available?
I have aftermarket torsion bars on my Toyota 4Runner and they are awsome off-road (no more bottoming out or crazy suspensions bounce).
I have not been able to find any.
I would like to put some HD torsion bars on, but somehow, I don't think that will work.
Any input would be appreciated.

I take it, they don't make any aftermarket torsion bars for Z71's, right?

I must be in the wrong collum, My silver has twisty bars,I put the 2inch lift and the Rancho rs9000 shocks all the way around. Feels real good now .

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