surface hardened mopar cranks

i have 1 of the 1053 surface hardened cranks in a 3.351 stroke that mopar performance offered and my ? is if this is turned do i need to have it rehardened? also what were the stock cranks made from material wise? info please! thanks dave

OEM cranks were forged from 1053 steel as well. (.48-.55% Carbon content)

Nitrided steel will generally have a case depth of .020", if that was MP procedure.

.020" case depth from the surface would mean you could theoretically grind the
crank -.030" and still have .010" hardened material.

FYI, Shaft Tech in Fostoria, OH can heat treat, grind etc.

thanks for the reply. not sure on the depth of hardness. the hemi cranks were surface hardened but only a couple of thousands or less from what i've read on them and that's why i'm asking, trying to find out about how deep and if it's really needed or was it a sales come-on. thanks again. any other info out there?dave

Pretty sure hemi cranks were Tufftrided.(less depth different process) Max Wedge cranks were Nitrided.Old MP cranks(Kellogg) and performance cranks were better material and Tufftrided if I recall correctly.Quality was very good for the most part.

It is pretty hard to find a shop who can do a chemical heat treat to a crankshaft anymore. The EPA has shut down most of those places.

It isn't clear to me that you need a heat treated crankshaft for general use. High powered combos are probably best off with a new forging anyway. We stopped worrying about heat treating used cranks years ago when it became basically impossible to get the job done anymore.

If you have a Callies crank they'll take it back and do a surface treatment but I don't think they do other people's cranks. Might be worth a call if you're really serious about getting the work done.

Dave, The cranks in both of my engines are factory forgings and neither has been rehardened after grinding. I haven't seen any issues yet.