Mike, its not loud enough to hear over an exhaust. If I barely turn up my radio I cant hear it at all. And remember, Im running a stock exhaust, so my car is really quiet without the radio on and the windows up. Yet, I could of sworn the little bit of sound goes away at open throttle. But the rise in rpms could be drowning out the sound.

I think all of the Walbro's are the same for the S13/S14 US Chassis..either way, its a simple install and I dont think theres much of a difference in fitment. The pump alone is half the size of the factory unit. A tie strap and your good to go