If you search hard enough, you can probably find a LT1 F-body for $3000, although as I'm searching through the local stuff, the 'decent' ones are going for $4000. It might be different where you are... out here they're still a bit 'popular'.
275-285hp (dependin on year), 325ft-lbs and a 6-speed transmission. Upwards of 25-26mpg highway if it's in good tune and you're real gentle with the throttle.
There's always 5.0 Mustangs as well.
Hey, you said fast, you didn't specify which direction.