The problem with all of my friends 2.5's are that they spin them to the moon and they "pop". I'd be the same way, heat of the monent hammer down!! If you got it why not use it? I've turned down allot of races because of having a smaller motor, people just think I have a big motor because I've got a 2.5 cowl on it. I know me and if I have that "big" motor than I'll use it and make it faster then I'll break it. This is why I'm going back all stock!!