Modding tuning and best performance upgrades on the Mercedes M277 engine!

All you need to know about "M277 Modifications"

M277 Modifications Guide

How to modify and upgrade the Mercedes M277

"Comprehensive guide to tuning the Mercedes M277 engine!"

TorqueCars often are seeing threads asking about how to improve the M277 from people inquiring about getting more power from the M277 and wanting to know what are the things tuners are recommending when it comes to M277 mods that work. So let us look into Mercedes M277 parts and outline the best mods that work on this great engine and point out some potential pitfalls along the way.

We shall review M277 tuning and show the best modifications for your car. Mercedes M277 great bases for a tuning project and with the right modifications like remapping, turbo upgrades and camshafts you will definitely increase your driving experience.

The greatest M277 parts on an engine are obviously the ones that give the best power gain for your hard earned cash.

We won't be swayed by popular M277 parts, they need to be cost effective.

M277 induction kits

Improving air intake on the M277

You need fuel and air for an engine to work. If there is a lack of fuel then it will run lean, if there is little flow of air it runs rich losing power . We'll pick up on fuelling later in this article but for now we shall look at air supply.

So the primary aim to any engine modification project to get fuel and air into your M277 but this has a knock on effect with the air flow sensor.

You'll commonly see there is a limitation in the air flow sensor AFM/MAP on the M277 when considerably more air is being drawn into the engine.

You'll see that 4 bar air sensors coping with quite large power gains, whereas the OEM air sensor was restricting bhp at a much lower level.

Intake manifolds transmit the during the engines suck phase from the intake filter and allow it to be drawn into the engine and mixed with fuel.

The shape and flow rate of the Air Intake manifolds can make a large effect on to fuel atomisation on the M277.

Commonly we find the intake headers are needing a performance upgrade, although a few OEM provide reasonably good intake headers.

Adding a M277 larger valve kit, getting 3 or 5 angle valve jobs and porting and head flowing will also boost performance, and as an added benefit will afford you raising the performance increase on other upgrades.

M277 performance cam tips.

Each engine responds better to more aggressive camshaft durations so view each engine as unique.

The ecu map and fuel pump and injectors also have a large bearing on the bhp gains you'll make.

Altering valve 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.

Significant air intake, and exhaust improvements on the M277 can be made from cam upgrades. Changing the cam profile alters the intake and exhaust durations on the engine and can dramatically change the bhp and power output.

NB: Fast road cams commonly boost the power over the rev range, you may sacrifice a little low end torque but your higher rpm power will improve.

Competition cams, boost the higher rpm power band but as a result the car will not idle smoothly and low end power nearly always suffers.

In a daily driver you should ideally to optimize your engines power to your cars usage.

I'd never find a M277 Motorsport cam is a pleasure to live with when in heavy traffic.

Stage 1, 2 and 3 mods for the M277

Before we break the best tuning upgrades down into stages of tune, let's list the most effective tuning upgrades for you.

  1. Suspension Upgrades - always improve your cars handling
  2. Brake Upgrades - Even before adding power improve those brakes
  3. Intake - make sure the intake is not restricted, use filters and intake upgrades to improve this
  4. Exhaust - as with 3 ensure there is not restriction in the exhaust, cats are the usual bottleneck
  5. Tunes - remapping, piggyback ECU's and aftermarket ECU's can all make decent gains
  6. Fuelling - when you've increased power you'll need to match this with more fuel
  7. Turbo upgrades - Improving the intake with a large turbo and better flowing intercooler will be the biggest power gain you'll see (but one of the most complex).

This video guide to tuning cars is a great starting point to work from in your project.

Stage 1 M277 parts:

Remaps/piggy back ECU, Sports exhaust manifold, Fast road camshaft, Panel air filters, Drilled & smoothed airbox, Intake headers.

Stage 2 M277 parts:

Sports catalyst & performance exhaust, Fast road cam, Ported and polished head, induction kit, high flow fuel injectors, fuel pump upgrades.

Tuning tips and articles Engine tuning Transmission tuning Care care Intake & exhaust mods Improve handling Forums

Stage 3 M277 parts:

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

Carefully think through your options and then buy your upgrades and set yourself a power target to save yourself from expensive mistakes.

Remaps helps fully realize the full potential of all the tuning parts you've done to your M277.

You will typically expect to see gains of approximately 20-30% more power on turbocharged vehicles and you can expect to see around 15% on NASP engines, but the end result will vary depending on the tuning parts you've done and the condition of your engine.

Turbo modifications on the M277

To get a turbo working on a NASP engine there is a lot involved, from lowering compression ratio to improved fuel supply and mapping, so we have found a great guide to helpavoid the common pitfalls or end up with an unfinished project because you were not told what you were getting into by doing this on the M277.

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

If an engine is turbocharged, upgrades are simpler to install and turbo engines are made using uprated components.

However you will find an engines have weakspots

It is important to find these restrictions and upgrade to higher quality components to handle the power.

We see many drivers spending a lots of money on turbo charger upgrades on the M277 only to experience the whole thing go up in smoke on it's first outing after it's been finished.

Large capacity turbochargers tend to experience low end lag, and low capacity turbochargers spool up really quickly but do not have the peak rpm torque gains.

We are pleased that the world of turbo units is always moving on and we commonly find variable vane turbo units, allowing the vane angle is altered according to speed to lower lag and increase top end torque.

Twin scroll turbo units divert the exhaust flow into two channels and flow these at differently angled vanes in the turbocharger. They also boost the scavenging effect of the engine.

Beefing up the air intake by adding a supercharger or additional turbo will help you achieve very large torque gains, although more difficult to get working. We have this feature on twinchargers if you want to read more.

Tips about fuel supply on the M277

When you improve the torque you will need to look at to the fuel system.

More torque needs more fuel. Experienced mechanics will tell you to be generous with your injector capacity.

The accepted safe increase is to add another 20% when buying an injector, this allows for injector deterioration and affords you some spare capacity should the engine require more fuel.

Don't forget that different fuel grades will usually require different settings, a high octane fuel will burn more efficiently than lower octane fuel for example. A car will trim fuel supply to keep within the ideal air fuel mix but at the extreme ends you may need to adjust your injector capacity, or the mapping or you'll get flat spots and potential lean or rich fuel issues..

Recommended M277 performance exhaust upgrades

Only look to replace your exhaust system with an upgraded one is if the existing exhaust is creating a restriction.

On most factory exhausts you'll find your flow rate is ok even on modest power gains, but on a serious tuning project with a big boost in power you will certainly need to get a better flowing exhaust.

Don't go with the biggest exhaust you can buy you'll reduce the exhaust flow rate - the best for power gains are usually between one and a half to two and half inches. Your exhaust design, the bend angles and construction are what have more effect on flow rates than your pipe width to a certain extent. So the exhaust design is a big factor.

Usual exhaust restrictions are traced to the catalyst installed, so adding a better flowing high performance alternative will help avoid this restriction.

Cat bypassing (NB:catalysts reduce harmful engine emissions) is illegal in most countries and regions.

Faults issues and things to look out for on the M277

Like most engines an M277, should have few issues if it gets properly serviced and looked after.

We cannot stress enough the need for oil changes with the correct grade of oil on the M277, failure to do this will exacerbate engine wear, on a tuned M277 this is more important than ever and close attention should be paid to your maintenance schedule.

If you are interested in learning more or getting impartial tuning advice for your M277 why not pop over to the forums at TorqueCars where you can chat about M277 tuning options and read about others projects who may be planning to do similar modifications on their M277.

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