I've been running 20% since I broke in my OS18 engine, I'd like to move up to 30% since my LHS is having a sale and is selling a 30% gallon as little as $15 since they're closing down temporarily. Is a process I have to do to change the fuel? Or should I just use it regularly? Do I have to make anything else to go BACK to 20% if I need to?

Just re-tune for whatever new fuel you get. Start off with rich settings, warm up the engine and tune normally. You don't need to do anything else. This holds true anytime you switch fuel - whether you go up or down in nitro makes no difference, just re-tune for the new fuel.

Aweome thanks alot. I got worried since someone told me that sometimes it's impossible to change fuel because the car just wont start up.

also with 30% your engine should run cooler at prime tune. if you tune by temp you may notice this.

Doesn't 30% mess with your engine at all?

ive always had much better luck with 30%. for me its easier to tune and my engines seem to run much more consistent and reliably. havnt heard of engines getting trashed from switching fuels. i used to run traxxas fuel but ever since ive switched to byrons ill never go back.

Hm..I should move to 30%...

Is the power gain noticeable?

yes it is very noticeable. if it is tuned correctly.