In-line 6-cylinder engines make sense from a 'primary & secondary balance' perspective.
"All V6 engines with even firing spacing—regardless of the V-angle between the cylinder banks—are subject to a primary imbalance caused by each bank consisting of an inline-three engine, due to the odd number of cylinders in each bank. Straight-six engines and flat-six engines do not experience this imbalance. To reduce the vibrations caused by this imbalance, most V6 engines use a harmonic damper on the crankshaft and/or a counter-rotating balance shaft".
Vee engine were born for a packaging need. The V6 sweet-spot is a 120º Vee between the banks, which would be impractable for most packaging. 60º is an accepted compromise.
en.wikipedia.org
The V8 sweet spot is a 90º Vee.
"All V6 engines with even firing spacing—regardless of the V-angle between the cylinder banks—are subject to a primary imbalance caused by each bank consisting of an inline-three engine, due to the odd number of cylinders in each bank. Straight-six engines and flat-six engines do not experience this imbalance. To reduce the vibrations caused by this imbalance, most V6 engines use a harmonic damper on the crankshaft and/or a counter-rotating balance shaft".
Vee engine were born for a packaging need. The V6 sweet-spot is a 120º Vee between the banks, which would be impractable for most packaging. 60º is an accepted compromise.
V6 engine - Wikipedia
en.wikipedia.org
The V8 sweet spot is a 90º Vee.
