Your not subpose to use caster oil for the pharmacutical?I'd use it in my motor it's synthetic and cost 3.99 for 6oz. I'm going to ask you guys this? I have Traxxas 33% nitro fuel and it has 10% oil mix in it.I need to bump it up to 18% because I'm running nitro boats! and I'm out of the 20% nitro and the hobby shops around me dont have the 30-40% nitro fuels.How much oil do I add in a quart?[&:]