I finally got some running time on my OS FT160. I used the updated Reichmuth ignition, now being manufactured by Ridge Machine Company. The system uses two pickups set 23 degrees apart. The low speed pickup handles things up to 2000 rpm and the second one then advances the timing between 2000 rpm and 4000rpm where it reaches full advance. The system was chosen because it has very small plastic spark plug caps instead of the huge metal ones common to the Chinese systems. With the engine mounted on my 1/4 scale Cub those Chinese cap looked ridiculous.
The results using 93 octane gas 20:1 with Avenger oil and a 18-6 prop are 1400 idle and 7500 WOT. The most interesting part of this is Initial engine timing is low speed pickup set at 37 degrees BTC and the high speed pickup at 60 Degrees BTC. If I set the high speed pickup at the normal 28 degrees BTC and the low speed pickup at 5 degrees BTC the idle can be dropped to 1100 rpm but the best WOT speed is 5000 rpm. As an experiment I install a Chinese ignition system and found that I had to set the pickup at 60 degrees BTC to get the WOT rpm up to 7500. I've been talking to Ridge Machine about this and even spent 3 hours at their shop working with them and we could not figure out what was happening to cause the requirement for the large timing advance setting. Any ideas anyone?
By the way I found that the OS carb performs more than adequately.