Turbo is certainly an easy way to go,
since - if you stay under about 250hp,
and maybe 15 pounds of boost - there
are no internal engine modifications,
and the engine doesn't have to
be taken out of the frame.
Should be good for 215-220 mph.
You can sell the turbo system later to
recover some of the costs,
and put the back to stock
for pleasure riding or resale..............
Lol, no way are you gonna run 15psi on a turbo...with stock internals...make multiple passes, unbolt turbo, and go back to stock.
You'll be unbolting the turbo to rebuild the engine.