Hi Chuck, go to this forum for diesel buddies with lotsa info:
I hope you find a used Oliver Tiger that is affordable; used ones
are extremely collectable and will cost you $250-$300.
For what it's worth, a good C.S. Oliver repro will out turn
an original mkIII by 1,000rpm. I did the test myself.
I pitted the repro against an Original Oliver mkIII, run just 15 miutes apart.
I used the same prop and the same fuel. The CS engine
actually turned 1,050 rpm faster than the original engine.
However, the Original Ollie is fabricated to a much higher quality.
I recommend that instead of the "Real Ollie", You find a new or used
PAW .19 TBR instead. The .19 TBR is a twin ball bearing, very easy handling
engine that has the same power as a Fox 35 stunt. It also has noticably
more power than the PAW .15 TBR. Good luck;