Which engine is better and faster in a mazda 6, a 3.0L V6 engine or a 2.3L I4 engine?

The 2.3 is the best way to go. With the sport shift transmission, the 4 cyl has plenty of power. You of course get the best fuel economy with the 4 cyl, and the cost of the car will be less as well. You will also save on insurance. I drive the 4 cyl Mazda 6 and I would never get a 6 cyl.

Well, depends on which 2.3 liter your talking about. They make two, ones in the mazdaspeed 6, the other is in the 6i.

V6 is rated at 220hp or used to be. It might be 215hp now.

The factory 2.3L i4 (in the 6i) only has 155-160hp

The mazdaspeed 6 has a turbocharged 2.3L i4 rated at 265-274hp and also has AWD. combined that it has the most hp out of the bunch, and awd, its the quickest/fastest mazda 6 in the lineup.

The reason why the hp varies is they dropped the hp in the newer models, they just discontinued the mazdaspeed6 not too long ago.

The limiting factor is that the mazdaspeed model also weighs the most, at a whopping 3500-3600 pounds, its hefty!

Want a cheaper solution?? get a mazdaspeed3, its fwd but has 263 hp turbocharged 2.3L inline 4.

Or the new mx-5 with 160hp and it only weighs around 2500 pounds!!!

the v6 is faster but worse in fuel economy.

the v6 is faster ofcourse