For the stock XP Iridium spark plugs the gapping is .051, I would suggest not changing the stock spark plugs until your warranty has expired. Mazda tried giving me crap for changing mine.
What's the gap size for a 1.6 Mazda
The 2008 Mazda MAZDA6 has a 2.3 L base engine size.
The 2008 Mazda MAZDA5 has a 2.3 L base engine size.
The 2008 Mazda MAZDA3 has a 2.0 L base engine size.
A spark plug for a 2003 Mazda Protege has a 14 mm thread size, and a 19 mm reach. The gap is 1.1 mm.
The 2008 Mazda MAZDA6 has an inline 4 engine.
The 2008 Mazda MAZDA3 has an inline 4 engine.
The 2008 Mazda MAZDA5 has an inline 4 engine.
Mazda named their truck models by engine size, so a B2300 is a 2.3 liter engine.
The 2008 Mazda CX-9 has a 3.7 L base engine size.
The 2008 Mazda CX-9 has a V6 engine.
43 liter