Modding and performance tuning parts for the Mercedes M177 engine!

Tuning guide "M177 Modifications"

M177 Modifications Guide

How to modify and upgrade the Mercedes M177

"Comprehensive guide to tuning and performance parts on the Mercedes M177 engine!"

Forums like the one at TorqueCars are always seeing threads asking how to improve the M177 from people inquiring about getting more power from the M177 and wanting to know what are the optimum M177 power upgrades. So let us look into Mercedes M177 parts and outline the best modifications on this great engine and point out some problems along the way.

Our aim here is to detail the best approach to M177 tuning and point out the best modifications. Mercedes M177 make a good tuning project and with the best tuning parts like a remap, turbo kits and camshafts you will substantially enhance your driving opportunities.

The best M177 mods on an engine are in our opinion the ones that give the best power gain for your hard earned cash.

We won't be swayed by popular M177 mods, they need to be cost effective.

M177 induction kits

Improving air intake on the M177

You need air matched to fuel for an engine to work. If there is a lack of fuel then it will run lean, if there is not enough air it runs rich sapping power which risks damage to the M177. We'll pick up on fuelling later in this article but for now we shall look at air supply.

So Feeding air into the M177 engine is the main goal to any engine tuning project.

You'll commonly see there is a limitation in the air flow sensor AFM/MAP on the M177 when a lot more air is being sucked into the engine.

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

Intake manifolds transmit the air during the suck phase from the intake filter and allow it to be drawn into the engine cylinders.

Structure and flow characteristics of the Intake headers can make a big effect on to fuel delivery on the M177.

Most headers are needing performance upgrades, although a few makers provide well optimised headers.

Increasing the M177 valve size, getting M177 port enlargement and head flowing will also increase bhp and torque, and significantly will raise potential for raising the bhp and torque increase on other tuning parts.

M177 performance cam tips.

Some M177 engines respond better to less aggressive cam durations than others.

The engine timing and injectors and fuel pump also will make differences on the power gains you'll hit.

Longer 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 M177 cam will make a dramatic difference to the engine bhp. Choosing a higher performance cam profile raises the bhp accordingly.

NB: Fast road camshafts usually increase the bhp across the rev band, you may sacrifice a little low end bhp but your high end rpm power will be lifted.

Race camshafts, increase the high end rpm power band but as a result the car will not idle smoothly and low end power nearly always suffers.

For a road car you need to match your torque band to your preferences.

I'd never have found a M177 Motorsport camshaft is a pleasure to live with when in heavy traffic.

Stage 1, 2 and 3 mods for the M177

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 M177 parts:

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

Stage 2 M177 parts:

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

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

Stage 3 M177 parts:

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

The M177 engines respond well to upgrades and thanks to their popularity there is a lot of parts and tuning parts around.

ECU mapping helps fully realize the full potential of all the mods you've done to your M177.

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 power output usually rely on the mods you've done and the condition of your engine.

Turbo modifications on the M177

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 M177.

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.

When your motor has a turbo already fitted upgrades are relatively easy and you will discover turbo charged engines are made with harder and stronger components.

There are reliable limits for every engine, with some being over specified and some only able to handle stock power

Discover these limits and fit better quality components to utilize the power.

We see many people spending a lots of money on turbo upgrades on the M177 only to suffer the humiliation of seeing the car catastrophically fail soon after it's used on the roads.

Larger turbo units tend to experience low end lag, and little turbo units spool up quickly but won't have the peak rpm bhp gains.

Thanks to new tech the selection of turbo chargers is always evolving and we are seeing variable vane turbo chargers, allowing the vane profile is altered according to speed to lower lag and increase top end bhp and torque.

Twin scroll turbo chargers divert the exhaust gases into two channels and direct these at differently angled vanes in the turbo charger. 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 bhp gains, although more complex to install. We have this in depth look at twinchargers if you want to read more.

Tips about fuel supply on the M177

When you increase the bhp and torque you will need to pay attention to to the fuelling.

More bhp and torque needs more fuel. At this point we flag up the need to over specify your injector capacity.

The accepted safe increase is to add 20% when buying an injector, this accounts 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 M177 performance exhaust upgrades

Only look to boost your exhaust system with an upgraded one is if the existing exhaust is actually creating a restriction in flow.

On most factory exhausts you'll find your flow rate is still 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.

Sports exhausts will certainly help air flow out of the engine but do not go too wide or you could will reduce the flow rate. Stick to one and a half to two and half inches for best results.

Usual exhaust restrictions are in the catalysts installed, so adding a freer flowing 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 M177

Like most engines an M177, 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 M177, failure to do this will exacerbate engine wear, on a tuned M177 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 M177 why not pop over to the forums at TorqueCars where you can chat about M177 tuning options and read about others projects who may be planning to do similar modifications on their M177.

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