Originally Posted by
rcjetflyer0718-RCU
I have an Evolution 40NX in my sonic and it flies quite fast. Make sure the fuel you use for the 40 FP has plenty of castor oil and try a 9X7 prop.
Are you sure about using a 9X7?
I have a 25FP and the instruction book recommends using a 8X6, 9X5 or 9X6 so using a 9X7 sounds a bit small. I'd be looking at something in the lines of a 10X5 or 6.
18% oil would be fine for your 40FP. In fact, that's what I run in my boats, 18% oil with 50% nitro, never had an oil related problem. Then again, my boat engines run at 25K+ RPM so more oil is a good thing