Spark Plugs.

[tanuie]

Just curios, why do V6 engines tend to have two spark plugs per cylinder.
Not to bothered but I wondered why.

 

[Bellow]

They allow for a higher compression ratio (more efficient) with the chosen valve configuration, avoiding premature detonation via shorter flame paths.

 

[grober]

Same reason they have 3 valves assuming your are talking M112 here.
Inline-6 vs. V6 | EClassBenz.com

 

[nb_racing]

They allow for a higher compression ratio (more efficient) with the chosen valve configuration, avoiding premature detonation via shorter flame paths.

As above, and basically you start combustion at 2 points, rather than one.