Originally Posted by
g8tkeypur
Red Max 50=60% nitro if you are racing an OPS 21-80. Make sure you get MARINE fuel,car or plane fuel will make your rod disintegrate for sure. I'm everything OPSI love them for the money.
This is your best bet. 40% nitro with at least 18% oil.... Red Max is quality stuff. Same mix every time
Been using it for years. Idles nice and cleans out on the top end.