RE: Another large scale Impreza project
Yeah, the tank pressure can be increased with a hose...you might have seen a pic from my build or someone else's, lol. I wasn't satisfied, however, because of the oily pressure line and inconsistent pressure. After playing around with that, and changint the jets and needles for tuning, I just bought an aftermarket carb since it's so much less hassle to tune.
Don't worry about the questions, that's what we're all here for! In your first set of pics, the engine has a slide carb, with a float bowl. Basically it looks like a cylinder under where the carb attaches to the air intake. In there sits fuel, but only fills up when a floating piece of plastic goes below a certain level. Gas then flows back into the bowl by gravity, which is why these pocket bikes have the gas tanks mounted above the engines. The slide is a cylinder with a cut portion of it that moves up and down when you pull/release the throttle to let more air (and fuel) into the engine. On the other hand, the buterfly carb is more like opening a door to let more fuel in, and creates a suction inside of it, so you can mount the gas tank anywhere. It is also less prone to leaking than the carb with a float bowl if the RC flips over.
If you can take the air filter off and look inside or take a closer pic of the carb we can tell you which it is.
I'm from laval - about 3 1/2 hours away. Have fun in the snow!