TURN MY HEADPHONES UP
the memcal tune probably won't make *as* big of a difference on gas as petrol but for the price it's worth it. gas needs more timing at low rpm and less timing at high rpm, and even on the gas the memcal still controls the timing. so the stock tune doesn't have enough timing down low, yet it has too much up top. advancing the timing on the dizzy alone is dangerous practice because you risk detonation at high rpm. i would go for a foam tune over a dyno tune, its 15x cheaper and greenfoam is spot on with the 5ltrs. then all you need to do is get the gas tuned as well and it will be great.