Mercedes M274 Tuning

"All you need to know about tuning the Mercedes M274 engine!"

The Mercedes M274 make awesome project engines and with the ultimate motorsport enhancements like ECU maps, turbo improvements and camshafts you will definitely increase your driving fun.

This pages aim is detail the best approach to M274 tuning and highlight the premier mods that work.

History, Power & Specs of the Engine

M274 DE16 LA

95 kW (127 hp; 129 PS) at 5,000 rpm 210 Nm (155 lbft) at 1,200–4,000 rpm

2015–present W205 C160

115 kW (154 hp; 156 PS) at 5,300 rpm 250 Nm (184 lbft) at 1,250–4,000 rpm

2012–2013 W204 C180
2013–2016 W212 E180
2017–present W213 E180

M274 DE20 LA

115 kW (154 hp; 156 PS) at 5,000 rpm 270 Nm (199 lbft) at 1,250–4,000 rpm

2013–2016 W212 E200 Natural Gas Drive

135 kW (181 hp; 184 PS)  at 5,500 rpm 300 Nm (221 lbft) at 1,200–4,000 rpm

2013–2016 W212 E200
2013–2016 X204 GLK200
2014–2018 W205 C200
2015–present R172 SLK200
2016–present W213 E200

155 kW (208 hp; 211 PS) at 5,500 rpm  350 Nm (258 lbft) at 1,200–4,000 rpm

2013–2016 W212 E250
2013–2016 X204 GLK250
2014–2018 W205 C250
2015–2018 W205 C350e
2015-present V37 Q50/Nissan Skyline (2014-2019; 200GT-t DBA-ZV37/DBA-YV37)
2016–present W213 E250
2016–present W213 E350e
2015–2019 X253 GLC350e
2016–present Mercedes-Benz V-Class
2016-present CV37 Q60
2018-present Y51 Q70

180 kW (241 hp; 245 PS) at 5,500 rpm 370 Nm (273 lbft) at 1,300–4,000 rpm

2015–2018 W205 C300
2015–2018 W213 E300
2015–present X253 GLC300
2015–present R172 SLK300
2015–present X253 GLC300 / GLC300 4 Matic

189 kW (253 hp; 257 PS) at 5,800 – 6,100 rpm 370 Nm (273 lbft) at 1,300–4,000 rpm

2019–present W213 E300 EQ Boost

Tuning the Mercedes M274 and best M274 performance parts.

Best M274 upgrades

Just because particular tuning parts are appear in lots of M274 projects it doesn't mean you should fit it, instead we will concentrate on the top tuning parts that will give your M274 the biggest power gain return for your cash.

Instead of us falling into the common "if it's shiny and makes more noise it must be good" mentality of many car sites and mags.

Altering your M274 cam will make a dramatic difference to the engine power band. Choosing a higher performance cam profile raises the power band accordingly.

Fast road cams usually raise the performance over the rev band, you might lose a little bottom end torque but high end rpm power will be better.

Motorsport cams, raise the high end rpm power band but as a result the car will not idle smoothly and low end power nearly always suffers.

In a car used daily, really you should, ideally aim to match your torque band to your driving style.

I'd be amazed if you have found a M274 Race camshaft is a pleasure to live with when in heavy traffic because low end power will be very lumpy. Competition cams are designed for maximum power at the top end of the RPM range, a place that most daily commutes will not permit!

Each engine responds better to less aggressive camshaft durations than others.

The engine timing and fuelling also will say much on the bhp gains you'll get.

Extending exhaust or intake durations can alter the bhp band and on most engines the exhaust and intake durations do not need to match, although most cams and tuners use matched pairs there are some advantages to extending the intake or exhaust durations.

Please watch our video which covers the 5 principles of tuning your car. Be sure to keep up with our latest YouTube content and subscribe.

Best Engine Mods for your car

1. Engine Tunes - engine tuning/remapping provides the most advantage in terms of cost savings,  aftermarket ECUs, and piggyback ECUs are all alternatives.
2. Fast road cams are one of the most significant mechanical changes, but they must be installed by someone who knows what they're doing and they are not always easy to source but you might find a local firm to regrind a stock camshaft.
3. Intake and Exhaust - Note that on their own these mods will NOT ADD POWER in most cases, but they can help enhance power after other mods by removing the restriction.
4. Upgrades to turbochargers and superchargers - forced induction is the most efficient approach to increase air supply, allowing you to burn more fuel and make more power. It is one of the most costly upgrades but provides the best gains.
5. Head work - The goals of porting and flowing the head are to get air flowing into the engine while removing flow restrictions and turbulence.

Typical stage 1 mods often include: Fast road camshaft, drilled & smoothed airbox, Intake manifolds, Panel air filters, Remaps/piggy back ECU, Sports exhaust header/manifold.

Typical stage 2 mods often include: Fast road cam, induction kit, high flow fuel injectors, fuel pump upgrades, Sports catalyst & performance exhaust, Ported and polished head.

Typical stage 3 mods often include: Engine balancing & blueprinting, Internal engine upgrades (head flowing porting/bigger valves), Adding or Upgrading forced induction (turbo/supercharger), Competition cam, Crank and Piston upgrades to alter compression, Twin charging conversions.

Remaps allows a tuner to establish the full potential of all the upgrades you've done to your M274.

(In some cases, as the factory ECU is locked flashing is not an option, so an aftermarket ECU is the route to take, and many of these will outperform factory ECU's but make sure it has knock protection and that you get it setup properly.)

It will usually give you around 30% more power on turbocharged vehicles and you can expect to see around 15% on NA (naturally aspirated) engines, but power output usually differs on the upgrades you've applied and the condition of your engine.

It is the whole point to any engine modification task to get air and fuel into each cylinder

Intake manifolds transmit the air from the air cleaner and allow it to be drawn into the engine cylinders.

Design and flow rate of the Intake manifolds can make a noticeable improvement to fuel mixing and power on the M274.

I usually find intake are in dire need of performance upgrades, although a few OEM provide decently flowing intake.

Big valve conversions on the M274, doing a bit of port work and head flowing will also raise bhp and torque, and significantly will permit a better bhp and torque increase on other mods.

Turbo upgrades

NA (naturally aspirated) engines need quite a lot of work when you add a turbo, so we have a separate guide to help you take into account the pros and cons of going this route on your M274

The more air you can get into an engine, the more fuel it can burn and uprating the induction with a turbocharger upgrade makes significant power gains.

If your car has forced induction upgrades are giving better power gains and turbo charged engines use strengthened components.

However every engines have weakspots

Discover these limits and upgrade to stronger pistons, crank and engine components to handle the power.

We see many tuners spending a loads of money on turbo upgrades on the M274 only to watch the M274 throw a rod soon after it's been finished.

Bigger upgraded turbo chargers tend to experience no power at low rpm, and low capacity turbo chargers spool up much more quickly but do not have the high rpm bhp gains.

In recent times the market of turbochargers is always increasing and we are seeing variable vane turbochargers, permitting the vane angle is altered according to speed to lower lag and increase top end bhp.

Twin scroll turbochargers divert the exhaust gases into a couple of channels and flow these at differently profiled vanes in the turbocharger. They also increase the scavenging effect of the engine.

It is common that there is a limitation in the air flow sensor (AFM/MAF/MAP) on the M274 when loads more air is being pulled into the engine.

Going up you'll find 4 bar air sensors coping with quite large power gains, whereas the OEM air sensor was restricting bhp at a much lower level.

Adding a supercharger or additional turbo will make large performance gains, although harder to get working. We have this feature on twinchargers if you want to read more.

Fuelling

You will need to ensure that the engine is not starved of fuel so must pay attention to the fuelling when you start going beyond 20% of a performance increase.We strongly recommend you to over specify your injectors flow rate.

The accepted safe increase is to add another 20% when specifying an injector, this takes into account injector deterioration and affords a little spare capacity should the engine require more fuel.

We think this one is common sense, but you'll need to match your fuel injector to the type of fuel your car uses as well.

All the following flywheel power targets will assume an injector duty cycle of 80% and a base of 58psi of fuel pressure at idle.

4 Cylinder turbocharged engines

• 58 PSI 340cc/min 200hp
• 58 PSI 511cc/min 300hp
• 58 PSI 682cc/min 400hp
• 58 PSI 1022cc/min 600hp

4 Cylinder NA (naturally aspirated) engines

• 58 PSI 285cc/min 200hp
• 58 PSI 426cc/min 300hp

4 Cylinder supercharged engines

• 58 PSI 312cc/min 200hp
• 58 PSI 468cc/min 300hp
• 58 PSI 625cc/min 400hp
• 58 PSI 937cc/min 600hp

Exhaust

You may need to increase your exhaust if the existing exhaust is creating a restriction.

On most factory exhausts you should find that your flow rate is ok even on modest power gains, but when you start pushing up the power levels you will need to get a better flowing exhaust.

Sports exhausts generally help improve air flow out of the engine but avoid an exhaust that is too large or you could very well end up with a reduced flow rate. So generally speaking, keep to 1.5 to 2.5 inches as a rule of thumb.

Common exhaust restrictions can be traced to the emissions filters installed, so adding a better flowing performance catalyst removes the restriction. We note that performance cats perform similarly to decats and have the added benefit of keeping your car street legal, as decats or catalyst removal is illegal in most territories for road going cars.

Weak spots, Issues & problem areas on the M274

The M274 engines are generally reliable and solid units, as long as you follow the manufacturers service schedules, and use a good quality oil to ensure longevity. Few problems should happen as long as they are regularly serviced and maintained.

Carbon build up in the head, particularly around the valves which will sap power or create flat spots, this is a larger issue on direct injection engines but should be looked out for on all engines. We have tips on removing carbon build up.

Some of our members have had issues with flat spots or glitches after applying mods and upgrades or tuning, this is not usually related to this engines design, so instead see our article on diagnosing flat spots and problems after tuning which should help you get the bottom of this issue.

Regular oil changes are vital on the M274, especially when tuned and will help extend the life and reliability of the engine.

If you would like to know more, or just get some friendly advice on Tuning your M274 engine please join us in our friendly forum where you can discuss tuning options in more detail with our M274 owners. It would also be worth reading our unbiased tuning articles to get a full grasp of the benefits and drawbacks of each modification.

Please help us improve these tips by sending us your feedback in the comments box below.

We love to hear what our visitors have got up to and which modifications work best for you on your car. Which helps us keep our guides and tips up to date helping others with their modified car projects. Your feedback and comments are used to keep this page up to date, and help improve the accuracy of these M274 tuning guides which get regular updates and revisions.

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This article is flagged for an update, so please pass on specific tips below that I can include. All articles, and content was written by me, Waynne Smith TorqueCars founder. Some outlines are just too general so I appreciate your feedback and suggestions. This entry was filed under Mercedes. You can leave a response below or join our forum to discuss this article and car modification in detail with our members.

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