3.27 or 3.55?

[Chevyguy]

My 2.73 are just sooo tall, sometimes I have to downshift to 4th on the highway cus 5th is geared to about 250 mph at 6000 rpms.

3.73's will certianly hurt your highway mileage compared to the 2.73's no matter what the other guys say. For a mostly stock motor going higher than 3.55 with a T-5 may slow you down since the motor would run out of breath at the end of the 1/4 mile. If you have a intake swap this will greatly improve the high rpm breathing and make the 3.73 or 4.10 more usefull