Commentary

I love the V-8 engine. I love its low-end torque, and I love its creamy power delivery. Most of all, I love the way it sounds, whether it’s in a Detroit muscle car or a luxurious autobahn burner.

But after test-driving the newest batch of 6-cyl. engines from the world’s auto makers as part of Ward’s 10 Best Engines testing, I can’t help but think the days of the V-8 as a mainstream engine are numbered.

Despite grumbling by our most eco-minded judges, I still look forward to having one or two V-8s on our list for at least a few more years. The V-8 still has a future in key niches such as luxury and performance vehicles and light trucks.

But it is growing harder to see what value the V-8 badge brings to popularly priced cars and cross/utility vehicles. In these applications, a premium V-6 is better than a typical V-8.

It’s true when you have combustion events taking place in eight small cylinders there will be less vibration than that generated by a fewer number of larger cylinders. But as technology improves and fuel-economy rules tighten, the drawbacks of more cylinders, such as extra friction and complexity, are starting to outweigh the benefits.

With direct injection, forced induction and other technologies making V-6 and I-6 engines more power dense every year, it is clear that more displacement and two more cylinders do not automatically create a stronger, more desirable engine.

Despite the competence of most new 6-cyl. engines, this is a bitter pill for some.

But in the motorcycle world, where packaging and performance are even more important, and Honda and BMW are as dominant as they are in autos, the argument was settled long ago. Cylinder evolution has run its course. Simplicity and efficiency have won.

In the 1970s and 1980s, traditional U.S. and European 2-cyl. engines were thought to be headed for extinction at the hands of more sophisticated and vibration-free inline 4-cyl. engines from Japanese producers.

Based on the more-cylinders-the-better philosophy, Honda, Kawasaki and others then introduced inline 6-cyl. models.

Enthusiasts raved about their velvety power delivery and melodious exhaust note, but their popularity did not last into the 1990s. Now, 6-cyl. bike engines are a rarity.

The I-6s had too many parts and were hard to package, from their wide girths to six exhaust pipes. The marketplace determined six cylinders was two too many for most motorcycles. Now, two, three or four cylinders in various configurations are used.

During a recent nostalgic test drive of three restored I-6 monsters from 1979 and 1981, even the enthusiasts at Cycle World magazine – after gushing about their turbine-like smoothness and intoxicating exhaust notes – admitted the motorcycle industry jumped the shark with sixes.

Judging by the pace of change in automotive powertrains, I can’t help but think we will be saying the same about V-8s in a few years.

But this doesn’t mean we’ll be overrun with V-6s in the future. There are plenty of amazingly smooth, power-dense 4-cyl. engines waiting in the wings to replace them, too.

dwinter@wardsauto.com