I think that a big part of your issue is that you're comparing the Fit to much more powerful cars as a reference point of experience. You simply can't squeeze that much of a power increase out of it to bring it up to the league that you're used to.
I can identify with you on one of your cars... Jetta VR6. I owned a '98 Jetta VR6 2.8L . I believe it was rated at 174 HP. It was the quickest, nicest car I had owned yet. I smoked many a BMW, and V8 cars/trucks on occasion.
A big difference in that VW engine, is that you've got torque from a very low rpm... in my experience, from around 2000 rpm's, you've already got some power going.
A Honda engine, in particular the 4 cylinder 1.5L engine of the Fit, in comparison,
does not really kick in until maybe 4000-5000K rpm's.
This took some getting used to for me. But for me, the only way to drive it is in sport mode, with the paddle shifters, get to know the road speed for each gear, then have fun with it, down-shift to match rpm's, ride out the rpm's to at least 4 or 5K, and discover what it has to offer. The more you get to know the character of the engine, the more you have fun with it.
I've got the Fujita Short Ram Intake, and also the Skunk2 cat-back exhaust. I started with a K&N drop-in filter, which gave a slight noticeable boost, then upgraded the exhaust with the Megan racing bolt-on axle-back exhaust, and at that point I still wanted more, then ended up with the Fujita Short Ram Intake and Skunk2 exhaust system.
I had the same install challenge with the bracket. You have to reverse the bracket so the adjustment side is toward the intake rather than the battery side, which allows you to move the filter end downward to allow clearance for closing the hood of the car. The intake body doesn't really line up straight with the throttle body like you might expect.
At this point, with the intake and exhaust, I'm satisfied that I got more out of the engine, to a nice point of modest fun. I won't try to take on a VR6 VW, or most cars, for that matter, and expect to come out winning. I just try to enjoy the Fit because it is its own car and personality, something to be appreciated for what it is.
e.b.
