The Saito FA-30 MkI has an ABC cyl/piston setup.
The enlarged Saito FA-40 that followed shortly afterwards has an AAC setup. Saito was one of the first companies to solve the problem of coating aluminum with chrome
Clarence Lee gave a brief desctiption of the FA-30 Mk.I in his book "the R/C 4-stroke engine". You can read about it and several others of the early fourstrokes in his book. ItĀ“s on sale now at RCM for $2.50 - a steal!
I donĀ“t have access to Peter ChinnĀ“s tests for the FA-30, but the FA-40 Mk.I produced 0.59 bhp/lb and 1.15 bhp/cu in. (compared to 0.48 bhp/lb and 1.02 bhp/cu in. for the OS FS-60 Mk.I). Not that much of a difference, but the OS FS-60 is vastly more powerful of course (thereĀ“s no substitution for cubic inchesā¦.)
Saito recommended 10x4 to 10x6 props and regular 2-stroke fuel with castor oil and 5-30 % nitro.
I have a couple of Saito FA-30Ā“s, but they are all Mk.2, with the forged steel rockers rather than the spindly cast alu type of the Mk.I
I use 15-18 % full synthetic oil and 8% nitro. Both engines run sweetly and do 10.000 rpm on a Master black G/F 9x6 or a T/F Super-M wood 10x4.
Safe idle is just under 3.000, and the sound is very pleasant with the simple straight exhaust pipe.
I got both of mine used, second hand, and they seem hold up really well, the compression is great.
One of the engines had no compression seal when I got it. This was due to a bent exhaust valve, no doubt caused by over-revving by the previous owner. After replacing the bent valve the engine was back in top shape.
Send me a PM if you want a scan of the Saito instruction manual for the Saito