Modding uprating the Mercedes M270 engine!

The Lowdown on "M270 Modifications"

How to modify and upgrade the Mercedes M270

"Comprehensive guide to tuning the Mercedes M270 engine!"

Popular tuning sites like TorqueCars are regularly seeing threads asking about how to improve the M270 from people inquiring about getting more power from the M270 and wanting to know what are the ultimate M270 upgrades. So let us look into Mercedes M270 upgrades and outline the best mods that work on this great engine and point out some common pitfalls along the way.

The Mercedes M270 great bases for a tuning project and with the best tuning upgrades like ECU maps, turbo kits and camshafts you will dramatically improve your driving opportunities.

This pages aim is examine M270 tuning and highlight the premier modifications.

The optimum M270 tuning parts on an engine are as we have found the ones that give the biggest return for your money.

We won't be swayed by popular M270 tuning parts, they need to be cost effective.

M270 induction kits

Improving air intake on the M270

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

So it's important to any performance tuning project to force air into your M270 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/MAF/MAP) on the M270 when a lot more air is being sucked into the engine.

We see 4 bar air sensors coping with quite large power gains, whereas the OEM air sensor sapped torque at a much lower level.

Air Intake manifolds take the on the suck phase from the air cleaner and allow it to be sucked into the engine cylinders.

The size of bore and shape and rate of flow of the Headers can make a big change to fuel atomisation on the M270.

I usually find intake headers are in desperate need of a performance upgrade, although a few manufacturers provide fairly well optimized intake headers.

Adding a M270 larger valve kit, doing some port work and head flowing will also lift torque, and more importantly will permit increasing the torque increase on other parts.

M270 performance cam tips.

Each engine responds better to extreme cam durations check your engine on a rolling road.

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

Longer valve durations can alter the torque 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.

Altering your M270 cam will make a dramatic difference to the engine bhp. Choosing a higher performance cam profile raises the bhp accordingly.

NB: Fast road camshafts tend to push up the bhp and torque throughout the rpm band, you may sacrifice a little bottom end power but your high end rpm power will be lifted.

Motorsport and race camshafts, push up the high end rpm power band but as a result the car will not idle smoothly and low end power nearly always suffers.

A Motorsport cam is not great driving in heavy traffic.

You should ideally optimize your bhp range to your preferences so for a typical daily driver stick with a mild fast road M270 cam

Stage 1, 2 and 3 mods for the M270

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 M270 parts:

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

Stage 2 M270 parts:

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

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

Stage 3 M270 parts:

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

The M270 units make great tuning projects and we're pleased to see that there is an increase of modifications and performance parts out there.

Remaps should help to unlock the full potential of all the upgrades you've done to your M270.

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 outcome usually depend much on the upgrades you've applied and the condition of your engine.

Turbo modifications on the M270

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 M270.

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

If the engine has a turbo already fitted upgrades are giving better power gains and we find turbo charged engines are made using many forged and stronger components.

There are tuning limits for every engine, with some being very over engineered and some just sufficiently able to handle stock power

Discover these limits and install better pistons and crank to handle the power.

We see many mechanics spending a a stack of money on turbocharger upgrades on the M270 only to experience the motor catastrophically fail soon after it's been enthusiastically driven.

Large capacity turbos tend to suffer low end lag, and small turbos spool up really quickly but don't have the top end bhp gains.

We are pleased that the world of turbos is always evolving and we commonly find variable vane turbos, where the vane angle is altered according to speed to lower lag and increase top end power.

Twin scroll turbos divert the exhaust flow into 2 channels and direct these at differently profiled vanes in the turbo. They also help the scavenging effect of the engine.

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

Tips about fuel supply on the M270

You will need to ensure that the engine is not starved of fuel so need to uprate the fuelling when you start extending past 20% of a power hike. We would recommend you to be generous with your flow rate on the injectors.

The accepted safe increase is to add 15% to the flow rate when buying an injector, this allows for injector deterioration and provides a little 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 M270 performance exhaust upgrades

You only need to to replace your exhaust system with an upgraded one is if your exhaust is creating a flow problem.

On most factory exhausts you'll see the exhaust flow rate is still fine 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.

Sports exhausts can usually air flow out of the engine but avoid an exhaust that is too large or you may end up will reduce the flow rate. Stick to one and a half to two and half inches for best results.

The usual suspects causing problems in your exhaust flow rate can be traced to the catalyst installed, so adding a faster flowing sports alternative will help avoid this restriction.

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

Faults issues and things to look out for on the M270

Like most engines an M270, 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 M270, failure to do this will exacerbate engine wear, on a tuned M270 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 M270 why not pop over to the forums at TorqueCars where you can chat about M270 tuning options and read about others projects who may be planning to do similar modifications on their M270.

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