How can I increase fuel efficiency and power without damage to my engine?

Question

How can I increase fuel efficiency and power without damage to my engine?

Answer 1

ride the bus or routine maintenance along with obeying traffic laws.  

Answer 2

drive slower

Answer 3

Change your oil at prescribed intervals.  Make sure the tires are aired up correctly (consult the table on the door frame).  Drive smoothly without jackrabbit starts and panic stops.  When driving long distances use cruise control.

Answer 4

Keep your car in good shape. Do not drive aggressively.

Fuel additives, and all gadgets are just a waste of money.  

Answer 5

my answer is try to tone your car on auto shop...