I see many posts recommending reducing compression ratio in OS FP and LA 40 engines. The objective appears to be to delay ignition when using larger props. Why not use a cold plug instead? And maybe use less nitro as well. The higher compression ratio should provide more torque/power. What am I missing? Does this result in less stable operation?
The old baffle piston engines did seem more responsive to added nitro, but in Schnuerle ported R/C engines, I usually find 5% nitro is fine. For example, my Enya 40X can turn a 10x6 essentially the same RPM on 0%, 5%, and 10% nitro. The difference is that it is not stable on 0%, but 5% tames it right down. My current attitude is that if I feel the need for more power than 10% provides, I will install a bigger engine, rather than flog a little engine. More cost effective, given the price of nitro.
Jim
The old baffle piston engines did seem more responsive to added nitro, but in Schnuerle ported R/C engines, I usually find 5% nitro is fine. For example, my Enya 40X can turn a 10x6 essentially the same RPM on 0%, 5%, and 10% nitro. The difference is that it is not stable on 0%, but 5% tames it right down. My current attitude is that if I feel the need for more power than 10% provides, I will install a bigger engine, rather than flog a little engine. More cost effective, given the price of nitro.
Jim
