The Best Inline-Six Cylinder Engines Of 2020

The 3 Best Inline-Six Cylinder Engines For Cars - 2020 Model Year

Inline-six cylinders are making a comeback. Now that smaller turbocharged engines offer better power and better fuel economy, smooth I6 engines are making their way back into engine bays. The three best for 2020, according to Ward's Auto, in the 3.0L I6 in the BMW M340i (B58), the 3.0L I6 in the Mercedes GLE450 (M256), and the 3.0L I6 in the GMC Sierra 1500 (Duramax 3.0L).

Each of these engines are quite different, even though they're all the same displacement. The BMW is purely gasoline, the Mercedes is an electric-gasoline hybrid, and the GMC is a diesel. There's a wide variety of innovative technology used, like twin-scroll turbochargers, variable intake manifolds, variable geometry turbochargers, 48V hybrid systems, infinitely variable valve lift, and incredibly high fuel injection pressures. Check out the video to learn all about 2020's best I6 engines!

*Related Videos - KEEP LEARNING!*

Ward's Auto 10 Best 2020:

Engineering Explained is a participant in the Amazon Influencer Program.

Don't forget to check out my other pages below!

NEW VIDEO EVERY WEDNESDAY!

[BLH]

So Jason can produce 200 lb-ft of torque so, Jason = a three cylinder diesel engine

[ike]

The inline 6 twin scroll BMW is the best engine I’ve ever owned. Love my HEMI and my ‘Vette, but the power delivery, precise engine response, and throttle control from the bimmer is second to none.

[niurou]

Very happy to see I6 engines making a come back. I6 is smoother, simpler and more elegant than V6.

[Druwoods]

Wow Jason. I was looking back at all your videos over the years and just the volume of work you've compiled, not to mention the ever increasing quality, is truly impressive. You have my vote for best YouTube channel. You've truly earned it.

[hartsickdisciple]

The B58 is the best overall inline 6 on the market, IMO. It's one of the 3 or 4 best engines BMW has ever put in a road car. It pulls like a big block from low RPMs, is silky smooth, efficient, and makes great power all the way to redline. It also sounds fantastic.

[benlucas]

I lost it when you said "I believe that some people call this a tool" 😂

[handlealreadytaken]

The biggest thing that I’ve noticed with the BMW inline 6 is how smooth it is. The engine isn’t rattling itself apart when you get the rpms up.

[JeroenvanMontfort]

3:45 Thank you for pointing this out. I've been telling people who emphasize torque this for years, but nobody seems to agree with me that power is only the number that really matters. You explain it well and I'll refer to this video whenever I'm in another discussion. :)

[WhiteAndNerdy]

LOVE Inline Sixes. Both my vehicles have that engine layout. So smooth, and long lasting too!

[michaeleckhardt]

As always, great explanation for non engineers. I like your drawings and how you use them to explain what’s happens. Wish I had you as a teacher in physics. And watching your videos improves my understanding of technical english.
Greetings from Germany 🇩🇪
btw. The best engines I had in my cars are the BMW inline 6 (non turbo) with valvetronic and the coyote V8 in my 2019 Bullitt. The both rev as hell.

[PatrickRich]

"torque alone is a very meaningless number" THANK YOU! I wish manufactures would give us something like an "average power" figure, which would tell the story of actual usable power and ignore torque. Ideally just letting us see the entire power curve, but thats not likely to happen.

[peanuts]

Even though it's not a i6 but Jaguar's 300bhp TDV6 is a beast and deserves recognition

[james]

That same diesel engine in the silverado gets 33 mpg highway. Anyways it's nice to see a diesel truck engine in one of your videos rather than just performance gas engines. Maybe cover that new powerstroke with 1050ftlbs of torque

[paintballthieupwns]

BMW makes some amazing i6 diesels as well

[yves]

The Merc... what will the maintenance cost when the delicate components start to age. I have their M104 (i6, 1997) still running strong at 260, 000 Kms. But I won't blame Merc, they're testing interesting tech, and when the smoke clears, perhaps one of those techs will become mainstream. But I'm not in the mood to be a paying beta tester.

[penguinton]

Those green stars are so smart. It's a good way to answer people's questions and the whole EE video library gets to be used. You just made the quality of your videos even better.

[tommurphy]

Jason, that was outstanding. The Wards editors say "thanks" for the plug!

[zfloz]

Man, I've owned Merc v6 and Bmw i6 engines. On BMW they start being interesting engines, since they put duble vanos. Because the old ones the had smoothes but no low end torque. And that's reeely a sweet a engine.

[kprzyb]

I believe that BMW does actually vary the throttle valve opening but for the purpose of quick boost control. At least the logs I have seen from valvetronic equipped engines has had throttle valve not completely open at WOT. There is a MAP sensor pre and post the throttle valve which would indicate they are using it to precisely control boost pressure in the intake manifold. A side effect is it allows them to have a few PSI on tap without waiting for the turbo to spool up. There also appear to be some control related advantages to targeting a pressure differential over the throttle valve. Valvetronic is just another bonus on top of all that.

[soaringvulture]

These motors remind me of the last days of aircraft piston engines. Turbo-compound radials had terrific efficiency but they were huge complex maintenance nightmares. You're going to need graduate engineers to keep these things running. And you can't trust most graduate engineers with a wrench.