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If you take the internals from the 197 F4R and put them into the 172 block, and fit the 197 head, then yes it will fit, but bear in mind that the engine management isnt going to be an easy retrofit and the way the cam timing works is different between the two.
IMHO you would be better off just fitting a set of hotter cams and high comp pistons to the 172 engine, as those are the only significant differences other than the cam timing.
If you fit a 197 head to a 172 bottom end without also fitting the 197 pistons then you will end up with a compression ratio in the 8s which will be utterly useless unless you plan on turboing it too.
The head castings are machined totally differently, there is much more chamber in the 197 head as they use a much more intrusive piston.
The MWMsport turbo demonstrator has a 197 head on a 172 bottom end for this reason.