unleaded fuel only

[blueoval_boy]

I was wondering how much bottle can i use on 93 octane with my 5.0. and if i do go to 110, 116, will i have retune my engine(timing, a/f ratio etc.)

[mrr23]

most people use a 125 shot on a stock motor 5.0 with 93 octane.

other things we need to know is what's done to the motor. i.e. forged pistons, rods, crank, etc....

[nxcoupe]

with 93 octane, you can run up to a 150 shot with more retard. The higher octane fuels allow larger shots with more timing. Stay away from leaded fuels, they will ruin your O2 sensors.

[speedtweekerz]

higher octane fuels are basically a chemical timing retard i.e. they allow you to run more timing. so, the higher the octane you are running the more n2o you can run without backing the timing. tune your car for 93 since it is readily available at the pump and that will allow you to step up the shot safely when you go to higher octanes