using this...http://www.mysportscar.com/tools/topspeed.htm
and my tires (185/65/14), and assuming a 7200 redline

Si (hatchback/del sol)----158 mph
Si/Ex (2 and 4 door)------168 mph
lx/dx --------------------176 mph
cx/vx--------------------220 mph

thats all assuming you have a d16z6 or y8 and/or can safely rev to 7200.

my 140 mph estimate was using a si HB tranny on my b7 block which can only rev to 6400.

but thats a fun site to play around with anyhow....i use this link for gear ratios...http://home.cinci.rr.com/mistab0ne/tranny.html

have fun.