I herd from a friend of mine that it is best to stick with the same brand of fuel that you broke your car in with. Is this true or change the brand of fuel that I am using.

Just an old wives tale. You can change fuel anytime, you just need to retune. Some fuels are better than others, so switching could actually be a good thing.

It's OK to switch fuel brands, but it is best to stick with one specific % of nitro though.

ok thanks

I thought it's ok to go lower % nitro to higher % nitro (but never the other way around). Is this true? I'm almost done with my first gallon of 20% and want to try 30%.

it's perfectly ok to go to different nitro percentages
either going higher or going lower

the whole can go up but not down thing is another old-wives-tale

however, whenever you change percentages - be it up or down - you will have to retune
and often you will have to make other changes
like changing glow plug heat and/or adding/removing shims

You can safely go higher or lower - as long as you tune your engine to the new fuel it'll be fine.

I have a fuel question if yall don't mind. I have some old fuel.....like 2-3 years old. If anything has been evaporated out of it it would be the nitro methain, right. The oils and such should still be good? So you all suppose I can use it as brake in fuel??? Or should I just use it for the next bomb fire???

if it's that old, i'd say don't use it in a car. and i believe it's bon fire, not bomb fire. Unless you really are having a bomb fire, cause that would be pretty cool.

well I don't know what kinda fires you build but I build bomb ass fires.[8D] Maybe I'll just shoot it and see if it will blow up[sm=idea.gif][sm=spinnyeyes.gif]