When I got my Matrix TR Arena, it came with an "R2" glow plug. After break-in it ran very hot.....I saw temps at 300. I never even leaned settings after break-in!
I finally changed to a Thunderbolt "Medium" glow plug and then, what a difference! It ran so much better. (temps now at 280 MAX. Normally at about 250's). Only problem now.....plug is dead. It only lasted about 4 tanks. When I installed the "R2" plug again. It ran terrible. ... Not sure why the plug died. My friend ran his (a Hot Bodies Lightening Pro) with the same plug and his died too! Almost at the same time. We are running 20% Traxxis and Trinity Monster Brew.....