What is the easiest way to tell when HSN is at it's peak? I unfortunately have 5 litres of RTR Optifuel, so it's very smokey and that doesn't really tell me when it's perfect. Also, I have adjusted it (say one end of the HSN needle is at 12, it is now around 8, like on a clock), how many spins do I roughly do? Would the easiest way be waiting till it cuts out at full throttle then tune down from there?