Modding uprating the Mercedes M119 engine!

Car tuning tips:M119 Modifications"

How to modify and upgrade the Mercedes M119

"Comprehensive guide to performance tuning the Mercedes M119 engine!"

Popular tuning sites like TorqueCars often are getting emails requesting information on how to improve the M119 from people wanting to know what are the optimum M119 power upgrades. So let us look into Mercedes M119 modifications and outline the best mods that work on this great engine and point out some common pitfalls along the way.

We shall examine the options for your M119 tuning and report on the best modifications. Mercedes M119 are popular tuning projects and with the optimum motorsport modifications like remaps, turbo upgrades and camshafts you will dramatically improve your driving fun.

The ultimate M119 upgrades on an engine are sensibly the ones that give the best gains for your money.

We won't be swayed by popular M119 upgrades, they need to be cost effective.

M119 induction kits

Improving air intake on the M119

You need air and fuel for an engine to work. If there is not enough fuel then it will run lean, if there is not enough air it runs rich resulting in lost power which risks damage to the M119. 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 car tuning job to pull air and fuel into the M119 engine but this has a knock on effect with the air flow sensor.

You'll commonly see there's a restriction in the air flow sensor MAP/MAF/AFM on the M119 when a lot more air is being drawn into the engine.

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

The intake plenum take the on the suck phase from the filter and allow it to be sucked into the engine cylinders.

The shape and flow rate of the Air Intake manifolds can make a noticeable difference to to fuel atomisation and engine efficiency on the M119.

Most plenum chambers are improved through aftermarket parts, although a few manufacturers provide fairly well optimized plenum chambers.

Fitting big valve kits, doing some M119 port enlargement and head flowing will also lift performance, and importantly will afford you a better performance increase on other modifications.

M119 performance cam tips.

Each engine responds better to less aggressive camshaft durations so set your engine up on a rolling road.

The map and injectors and fuel pump also will make differences on the power gains you'll get.

Altering valve durations can alter the power 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 M119 cam will make a dramatic difference to the engine torque. Choosing a higher performance cam profile raises the torque accordingly.

NB: Fast road camshafts tend to increase the performance over the rpm band, you may sacrifice a little low end bhp but higher rpm power will be better.

Competition camshafts, increase the higher 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 you should ideally to match your engines power to your driving style.

I'd be gobsmaked if you have found a M119 Competition camshaft is a pleasure to live with when in heavy traffic.

Stage 1, 2 and 3 mods for the M119

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 M119 parts:

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

Stage 2 M119 parts:

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

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

Stage 3 M119 parts:

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

The M119 power plant respond well to upgrades and we're finding that there are plenty of upgrades and tuning parts around.

ECU flashing allows a tuner to release the full potential of all the mods you've done to your M119.

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 differs on the mods you've done and the condition of your engine.

Turbo modifications on the M119

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 M119.

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 an engine is turbocharged, parts are more reliable and we find turbo charged engines already contain more solid components.

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

Discover these restrictions and fit higher quality components to survive the power.

We've seen people spending a loads of money on turbocharger upgrades on the M119 only to experience the engine explode just after it's been finished.

Large turbo chargers tend to suffer a bottom end lag, and low capacity turbo chargers spool up more quickly but don't have the high rpm power band gains.

Thankfully the choice of turbos is always evolving and we now see variable vane turbos, permitting the vane angle is altered according to speed to lower lag and increase top end performance.

Twin scroll turbos divert the exhaust gases into a couple of channels and direct these at differently designed vanes in the turbo. 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 setup. We have this feature on twinchargers if you want to read more.

Tips about fuel supply on the M119

Don't miss you'll need to raise the fuel delivery when you are increasing the power - it makes the car more thirsty. Most tuners we speak with say to over specify your injector capacity.

The rule of thumb is to add 20% when buying an injector, which takes into account injector deterioration and provides you some spare capacity should the engine need 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 M119 performance exhaust upgrades

We'd only recommend you look to improve your exhaust system with an upgraded one is if your exhaust is actually creating a restriction in flow.

On most factory exhausts you should find that your flow rate is 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 balance the flow of gases through the engine.

But if the exhaust pipe is too big, ie: over two and a half inches diameter, you will lose a great deal of the exhaust flow rate and end up losing power and torque.

The usual suspects causing problems in your exhaust flow rate are traced to the filters installed, so adding a faster flowing race 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 M119

Like most engines an M119, 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 M119, failure to do this will exacerbate engine wear, on a tuned M119 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 M119 why not pop over to the forums at TorqueCars where you can chat about M119 tuning options and read about others projects who may be planning to do similar modifications on their M119.

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