Throw a "Canadian" (earlier model) Y-pipe at it and it'll really rip.
My old 5A was exactly what you have: stone-stock exhaust, ThermoQuad, Edelbrock intake and hotter distributor (from a '73 340 I happened to have lying around). The ex-fiancee shocked a lot of people with that car... though the deeper gears definitely helped. I was talking with a friend of mine that actually did the axle swap for me, since I was, uh, on a state-sponsored vacation at the time that was done, and he swears that axle was a 2.94. Either way, it was a much better car all the way around: reliability, performance, and fuel economy.
My old 5A was exactly what you have: stone-stock exhaust, ThermoQuad, Edelbrock intake and hotter distributor (from a '73 340 I happened to have lying around). The ex-fiancee shocked a lot of people with that car... though the deeper gears definitely helped. I was talking with a friend of mine that actually did the axle swap for me, since I was, uh, on a state-sponsored vacation at the time that was done, and he swears that axle was a 2.94. Either way, it was a much better car all the way around: reliability, performance, and fuel economy.
Damn its got a lot more power! 
