Why wouldn't you just build 198/210 then the only advantage I can see building 170/210 is a lighter piston which I can't see being a overly heavy piston in the first place, if you want a revver just build the 170.
The 198 is the same block as a 225 block. There is something said about de stroking on doug dutra's web site. I think along the lines of using the 198/225 block (raised block) an the 170 crank (low deck block). But its not really usefull unless your doing some form of forced induction as all 3 motors use the same 3.4 inch bore cyl. So you just end up with a 170 cid in a larger block. And depending on the rods, change the compression ratio. Which is where it could be useful for force induction (super charger).
The only stroked option is the small large block crank (the 198 cid) in the small 170 block giving you 210 cid.
