135 145 degrees  sleeve timing   190 crank timing

many stunt engines , people  use ,  will  run  from 125 degrees  to 150
and  crank timing  from 180  to 200  degrees

Randy

olde dungers like a Merco , with tiny round port and case port can be something like 45 - 45 .

Later the intake closes the more itll let it rev .
Parently the Mk III Rossi was a bit late at 62 , so could be awkward to restart in goodyear .

Typcal stunt ' Tourquer ' might shut aroud 45 or 50 .

A load or compete tripe , I should think . Being as stock theyre fine . But heres some drivle to peruse .

http://www.machineconcepts.co.uk/aeromodelling/st51/st51-1.htm#shaft

Seems hes sleeving down the shaft bore , The Olde ' increase the gas speed ' trick .

Like woton Rally Cars , where the smaller zorst tubing gets better throttle respose . Circuit and you go oversize for top end . Thar she blows .