Rust on caliper

[John Campbell]

<...and it was mentioned at the time that the rusted block was
<actually stronger than a new one.

I remember reading about this theory also. IIRC, the rust/corrosion is
similar to polishing in that any surface cracks or scratches are smoothed
into the surrounding area since. Those areas are the first to corrode and
once the rust is uniformly covering the surface the underlying metal is
protected. I think this is only with cast iron, not steel.

John Campbell
'02 WRX and Nissan free for the first time in 11 years : \