At 13.5:1 I wouldn't want to see you run much more than 30%. And was said by more than just me, start at 10% and work your way up. I have the conversion formulas for jetting enrichment w/ various percentages but due to the differences in specific gravity between methanol and nitromethane you really need to invest in a decent hydrometer. Kinsler has a good one and for the 0-50% model, it'll set you back about $130 +. Don't try to mix the stuff by volume. 3 gal nitro and 7 gal methanol doesn't compute to 30% w/ a hydrometer. Even temperature will change the percentage. Single batch (per run) mixing is recommended