Fox Engines
well, they are really popular engines. i can see why. take my os .91 pumped fs for example. the thing turns a 14x6 at 9500 rpm, and han handle up to 30% nitro without a shim, and can handle up to 40% nitro. if you take them uffler off, you get a lot more power, and idle is supurb. spools up perfectly.