Well it's been a while since I commented but I think Stu is correctly restating the question...What are fastest production cars..ie one that anyone with 20 to 25k could jump in and toast the pavement and still get back and forth to work in. cars that were made by the thousands.
No doubt the vetts are fast especially if you fool the gov's a bit. but at 40k a bit out of the ordinary guys reach. Now a used one will fit within the rules.
I had an 89 T-Bird super coupe (roots blower stock) many many of these were made. they went for 20k new 10 used. Anyone of these could and still can run 145mph and get 20 mpg or better. There is a huge cult forum of these and there are many pictures taken from the back seat of the speedo long burried with the tach at 4800 -5000 . they ran about 1800 rpm at 60 so you can see about 140-145 easy. I did it one time in mine that was enough. Not great drag racers except for a 3.8 they did make some power if you wanted to spend a bunch. They have a wicked top end and are deceptively quick from a rolling start.
The hot rod Mustangs are also some really fast and quick cars, Today Chrysler 300m and Hemi magnum are probably right up there. I sure there are some Camaros and Firebirds that can get with it too. I think the Cad with the NorthstaR was pretty fast too.

just my input

betnwings