Os 46fx
Joe with no class specific rules to consider the sizes I would try are APC D-1 props in 8.8x8.75, 8.8x9.0 and 8.8x9.0w sizes. Also a half wave tuned pipe called the 'Ultrathrust' from Dave Shadel at Performance Speciaties will add considerable 'go'. You will still not be up to the level of a Nelson or Jett engined Quickee but will be doing in the range of perhaps 125/130 and far faster no doubt than anything you have ever experianced before, perhaps fast enough.
John