No sarcasm here. You think 4/10s of a second is nothing? Professional racers spend seasons trying to improve their times by 4/10's of a second. You ran a 15.9 right? Put it this way, if you and I raced, I'd have you by about 5 car links just at the quarter mile, then, after the 1/4 mile (which is where my car actually starts to get fast) you'd be reduced to a tiny dot in my mirror. 4/10's may not sound like much, but at 85+mph, its a good bit.

91 awd: 60-1, 880's, E-Prom, etc.
93 awd: JDM 6 bolt, K&N, full exhaust, Wally 255, otherwise stock.

R.I.P. the original "Factory Freak"
15.5's with short ram and catback only
1996 RS 5-speed