Using new fuel
 

Hey guys, I picked up a Mbx5t from a guy who was running Byrons 20% and I am planning on switching it to 25% gen2. Ive never tuned an engine before but I understand the basics. From what I hear from the guys here I will end up having to lean it out a half turn or so. Should I go an hour at a time on the top end until it seems right? BTW it has an LRP .28 with less than 2g through it. Thanks for any help.

Make small adjustments. Remember good smoke,good throttle=good engine. I know some people only use that method to tune but I use a temp gun. As far as exactly how much you should turn your needles in, that will vary from engine to engine, temperature, humidity, many variables. I just made the same switch and my low side was more sensitive to the change but get your high side right first then work on the low.

Raising the nitro %, may need to reshim head button as well.

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The "racers" at the hobby shop said I would not have to going up 5%. Is it recommended that I do and how do I go about doing that?