The straight-six engine has a significant place in the history of German luxury vehicles. This engine layout, now the cornerstone of BMW's brand, is known for its smoothness. In many instances, smoothness means luxury. It is in part that smoothness that you are paying a premium for. This is why economy-focused turbo-four options offered by luxury brands never capture the essence of the brand as intended. Those engines often lack the necessary characteristics that create that smooth experience.

BMW believes in this ethos wholeheartedly and went all in on the straight-six engine many years ago. Their long-time rivals, Mercedes-Benz, have only recently seen the light regarding the straight-six engine. Mercedes had given up their straight-six efforts over two decades ago in favor of V-6 platform development. Yet, the luxury brand has seen that the V-6 engine, despite being capable, cannot replicate the inherent smoothness of an inline-six engine.

This is why there are only two notable straight-six platforms offered in 2024 model year cars today: Mercedes' M256 and BMW's B/S58. It is these two platforms that power all the models on this list, including a notable Toyota with a BMW heart.

In order to give you the most up-to-date and accurate information possible, the data used to compile this article was sourced from various manufacturer websites, including BMW, Mercedes-Benz, and Toyota, and other authoritative sources. The models below have been ranked based on their starting MSRP.

10 2024 BMW M240i Coupe

MSRP: $49,700

The 2024 BMW M240i Coupe is the cheapest car of any kind you can purchase new today with a straight-six engine. At just under $50,000, this German luxury coupe offers some serious performance per dollar.

Performance Specifications

The benefit of the non-xDrive Coupe model is you are getting the lowest curb-weight BMW available with the B58 turbocharged inline-six engine. Although not as stout of a performer, the M240i is lighter and almost $15,000 cheaper than the 2024 BMW M2.

Pros

• Lightest BMW with B58 engine available
• Impressive performance per dollar
• Best-in-class engine

Cons

• Heavier than its Toyota competition
• No longer available in manual transmission
• Hit or miss styling

9 2024 Toyota GR Supra 3.0

MSRP: $55,400

It's a BMW, it's not. It's a Supra, it's not. We don't care about all the politics, we have a 2024 Toyota GR Supra with a straight-six turbo and a manual transmission. That's a blessing.

Performance Specifications

What we do care about is that the 2024 Toyota GR Supra is an amazing performance deal. When considering its features and capabilities among all available straight-six models, its obvious qualities stand out even more.

Pros

• Lightest new vehicle available with the B58 engine
• Last of the manuals
• Unique standout styling

Cons

• 6-speed manual offered only for 2022+ model year
• Dealer markups at 3.0 or higher trim levels
• 2.0 models

8 2024 M340i Sedan

MSRP: $57,600

We hope there never comes a day when you can't buy a non-M 3-Series with a straight-six engine. Lucky for us, today is not that day and the 2024 BMW M340i Sedan remains a top choice for a reason.

Performance Specifications

With four doors and more than enough power to get rowdy, the 2024 BMW M340i Sedan makes little compromise on fun or practicality. BMW made the sports sedan platform its bread and butter decades ago and continues to dominate the segment today.

Pros

• Best-in-class engine
• RWD option available
• Four doors and leading performance per dollar in its segment

Cons

• Manual transmission is no longer available
• The heaviest 3 Series ever
• Steering is precise but numb

7 2024 BMW M2 Coupe

MSRP: $63,200

The S58 twin-turbocharged inline-six engine powering the 2024 BMW M2 Coupe makes it almost impossible to hate. Polarizing styling aside, the M2 Coupe offers a lot to love about it at an impressive price point.

Performance Specifications

With solid driving dynamics, a killer engine, and the right proportions, the M2 Coupe is the quintessential modern performance BMW. If you make calculations based on smiles per gallon, you will find it hard not to fall in love with what the 2024 BMW M2 can offer.

Pros

• Amazing power-to-weight ratio
• Lightest platform offering the BMW S58 engine
• Last of the BMW 6-speed manuals

Cons

• Heavier than previous generation 3-series
• Hit or miss styling
• Exhaust note is disappointing

6 2024 BMW Z4 M40i

MSRP: $66,450

BMW's sporty roadster continues its straight-six heritage with the 2024 BMW Z4 M40i. We are also impressed that BMW still offers the 2024 Z4 with a 6-speed manual transmission.

Performance Specifications

One of the Z4 M40i's greatest selling points is its weight. Compared with the 2024 BMW M440i Convertible at well over 4,000 pounds, the 2024 Z4 M40i manages a weight under 3,600 pounds. This is a massive difference and one you can feel. Thus, if you want to go topless and still enjoy an inline-six engine, the 2024 Z4 M40i is a great choice.

Pros

• Best-in-class engine
• The lightest convertible BMW with the B58 engine available new
• Solid cargo space in its segment

Cons

• Should handle better considering its weight
• Toyota GR Supra exists
• $10,000 increase over the GR Supra

5 2024 Mercedes-Benz E 450 4MATIC Sedan

MSRP: $68,100

Mercedes returns to the straight-six platform with the 2024 Mercedes-Benz E 450 4MATIC Sedan. $68,000 is the entry price point to experience the reborn M256 inline-six engine.

Performance Specifications

Mercedes knew if they committed to the inline-six engine again, they couldn't just copy what BMW was doing and hope for the best. This is why the M256 inline-six found in the E 450 model offers some innovations their German rivals don't.

Pros

• Innovative 48-volt system integration
• Comparable power output to its direct competition
• The future of Mercedes combustion engineering

Cons

• Unproven long-term reliability
• Losing complexity in one area to increase it in others
• More expensive than its direct competition

4 2024 AMG CLE 53 Coupe

MSRP: $72,800

The 2024 AMG CLE 53 Coupe is Mercedes' way of saying the inline-six platform is back and means business. Boasting 443 horsepower and innovative technology at every corner, the CLE 53 is a new chapter in the German brand's performance legacy.

Performance Specifications

A notable upgrade compared to non-AMG inline-six Mercedes models is the introduction of the supplemental electric supercharger. This addition helps feed an already larger twin-scroll single turbocharger to near instant levels of responsiveness.

Pros

• Impressive power output
• Leading performance technology integration
• A breath of fresh air in the Mercedes line-up

Cons

• Unproven long-term reliability
• Losing complexity in one area to increase it in others
• The rarity of this AMG model can be both good or bad

3 2024 BMW M3 Competition

MSRP: $80,200

The BMW M3 has been the Bavarian brand's performance showcase for decades. The 2024 BMW M3 Competition adds to the M Power brand's continued history of performance dominance.

Performance Specifications

The S58 inline-six engine found in the 2024 BMW M3 Competition is one of the most powerful variants available with a bit over 500 horsepower. This Competition model is willing to undertake any challenge you may throw at it. Even at this price point, you seldom find another performance vehicle capable of going pound for pound with the BMW M3 Competition.

Pros

• Unrivaled overall performance capability
• Over 500 horsepower from the leading performance inline-six engine on the market
• 4-doors means fun without losing basic practicality

Cons

• Competition model exclusively available with 8-speed automatic
• The tread of increasing curb weight
• More competition in the luxury performance market than ever before

2 2024 BMW 840i Coupe

MSRP: $90,800

At near $100,000 price point, the 2024 BMW 840i Coupe is one of the most expensive BMW models offering the B58 inline-six engine. Despite its sexy, aggressive styling, the BMW 840i is lackluster in its performance compared to other flagship coupes in this price range.

Performance Specifications

Once you start speaking about $100,000 price points, that becomes Porsche 911 range. Despite this, the 840i configuration of the 8-Series is available in an impressive variety of body styles including: Coupe, Gran Coupe, Coupe Convertible and Gran Coupe Convertible. The 840i is the perfect car for a dashing executive, but you really need to fall in love with the styling from top to bottom to justify the price point.

Pros

• Sexy styling demands attention
• Sumptuous luxury inside and out
• Every body and drivetrain configuration you could dream of

Cons

• 840i model could offer better performance per dollar
• Stout competition at this price point
• Added size = weight

1 2024 AMG GT 53 4-door Coupe

MSRP: $109,350

The most expensive inline-six powered car available on our list is the 2024 AMG GT 53 4-door Coupe. Despite costing almost $40,000 more than the AMG CLE 53 also on this list, it offers both less power and torque output. Is this high-octane 4-door with coupe styling worthy of this high price point?

Performance Specifications

Considering the twin-turbo V-8-powered AMG GT 63 model starts at an eye-watering $153,350, you might say the 53 model is a steal. Anyway we look at it, the AMG GT 53 is a crazy excuse for a family-focused vehicle. Yet, it does display the versatility of the inline-six platform in a space that has been traditionally dominated by V-8 engines for decades.

Pros

• Rarity and uniqueness
• Undeniable luxury and comfort
• As reasonable a daily as any other $100,000 luxury sedan

Cons

• $100,000 price point is a tough sell
• Performance per dollar is lacking
• A niche vehicle for a niche market