The Tigre only needs 5% nitro to idle and transition superbly. Burning low nitro (5%) fuel with a prop that will let the engine rev into the design range will minimize fuel consumption and will extend engine and glow plug longevity considerably. Pattern flying isn't racing. There are no extra points for going extra fast. Consistency is more important than all out speed. Consistency is one of the reasons that I've always liked ST/Webra/OS engines over some other, higher powered, but flakier, engine brands (not Rossi).

Pick up a Jett or Ultrathrust muffler for the engine and prop the engine to run in the muffler maker's rpm range. This means no 12x7 or 12x8 props on a 10cc engine that is not a long stroke, lower rpm engine, such as the OS SF and RF series. You should be trying 11x7, 11x7.5 to 11x8 props, or even a few 12x6 props if you need the vertical emphasis. Not all props load the engine equally, so be sure that whichever prop you use keeps the engine in the Jett or Ultrathrust muffler's recommended rpm range.

I've switched from Perry and Robart pumps to Cline and Iron Bay fuel pressure regulators. They are much easier to dial in. In fact, most times, there is no dialing in at all. They work best when the tank is pressurized by two-stroke crankcase pressure lines fitted with a check valve (one way valve). This is a very easy mod (adding a lower crankcase pressure nipple to a two-stroke glow engine) to do, but if anyone has trouble, feel free to contact me and I'll walk you through it, as will many others here on RCU, I'm sure.

Stay with the .60 engine, but keep the fuel costs down by staying with 5% (or less) nitro in the fuel. The ST engines will tolerate straight synthetic oil easily, but I always run a tad of castor oil in the mix. It can't hurt and it doesn't add much of a mess to clean up. Good luck and let us know how you are doing.


Ed Cregger