a few years back at VSC I was running a s/t 46 on a jamason with 22% oil Powermaster  10% nitro / I could not get a steady run, a wise old man ,Bill Haywood gave me some 10%fule with 28% oil and the Tigre ran great all weekend .
 this weekend a friend of mine was running a S/T 46 on 22/10 and could not hold a setting for 6 test flights   today I added some caster to his fuel and he had 2 perfect runs without ever touching the needle