Tuning the Mercedes M113

"Comprehensive guide to performance tuning the Mercedes M113 engine!"

We often are getting emails asking about the ultimate M113 power upgrades. So let us look into Mercedes M113 upgrades and outline the best modifications on this great engine and point out some frequent tuning mistakes along the way.

Here we look into M113 tuning and report on the optimum upgrades. Mercedes M113 provide a fun base for your project and with carefully chosen uprated parts like remapping, turbo kits and camshafts you will noticeably enhance your driving pleasure.

The best M113 tuning mods on an engine are in our opinion the ones that give the best value for money.

We won't be swayed by popular M113 tuning mods, they need to be cost effective.

Altering your M113 cam will make a dramatic difference to the engine power band. Choosing a higher performance cam profile raises the power band accordingly.

NB: Fast road cams commonly push up the performance through the rpm band, you may sacrifice a little low down power but high end rpm power will be lifted.

Race cams, 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 won't do well if in heavy traffic.

You should ideally match your bhp range to your cars usage so for a road car stick with a fast road M113 cam

Some M113 engines respond better to less aggressive camshaft durations so set your engine up on a rolling road.

The ecu map and fuelling also will say much on the bhp gains you'll make.

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.

M113 Tuning Stages

Stage 1 M113 modifications: Intake headers, Sports exhaust manifold, Drilled & smoothed airbox, Fast road camshaft, Remaps/piggy back ECU, Panel air filters.

Stage 2 M113 modifications: Sports catalyst & performance exhaust, high flow fuel injectors, Ported and polished head, fuel pump upgrades, Fast road cam, induction kit.

Stage 3 M113 modifications: Twin charging conversions, Crank and Piston upgrades to alter compression, Competition cam, Engine balancing & blueprinting, Adding or Upgrading forced induction (turbo/supercharger), Internal engine upgrades (head flowing porting/bigger valves).

ECU flashing allows a tuner to release the full potential of all the upgrades you've done to your M113.

It will usually give around 30% more power on turbocharged vehicles and you can expect to see around 15% on NASP engines, but your results may vary depending on the upgrades you've applied and the condition of your engine.

It is vital to any tuning job to feed more air and fuel into your M113

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

The bore size, shape and flow rate of the Air Intake manifolds can make a substantial difference to to fuel atomisation and engine efficiency on the M113.

Most intake headers are improved through performance upgrades, although some OEM provide decently flowing intake headers.

Increasing the M113 valve size, getting M113 port enlargement and head flowing will also boost bhp and torque, & more importantly will make space for a greater bhp and torque increase on other parts.

Turbo upgrades for the M113

NASP 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 M113

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 a car has a turbo already fitted mods are going to net you a larger power gain and you will discover turbocharged engines already contain strengthened components.

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

Discover these limits and install higher quality components to handle the power.

There are many car owners spending a a stack of money on turbocharger upgrades on the M113 only to suffer the indignity of watching the motor literally blow up just after it's first rolling road session.

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

In recent times the selection of turbochargers is always moving on and we commonly find variable vane turbochargers, permitting the vane angle is altered according to speed to lower lag and increase top end torque.

Twin scroll turbochargers divert the exhaust gases into 2 channels and feed these at differently profiled vanes in the turbo charger. They also help the scavenging effect of the engine.

It is common that there is a restriction in the air flow sensor AFM/MAP on the M113 when considerably more air is being sucked into the engine.

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

Adding a supercharger or additional turbo will make large torque gains, although more difficult to configure. We have this article covering twinchargers if you want to read more.

Uprating M113 fuel injectors

You will need to ensure that the engine is not starved of fuel so will need to pay attention to the fuelling when you start extending past 20% of a power increase.It is important to over specify your injectors flow rate.

The rule of thumb is to add 20% capacity when buying an injector, this allows for injector deterioration and affords some 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.

Best M113 performance exhausts

You should look to increase your exhaust 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 when you start pushing up the power levels you will need to get a better flowing exhaust.

Sports exhausts will certainly help air flow through the engine but avoid an exhaust that is too big or you could will reduce the flow rate. Stick to 1.5 to 2.5 inches as a rule of thumb.

Common exhaust restrictions are traced to the filters installed, so adding a better flowing sports alternative will help avoid this restriction.

Problems and issues to look out for on the M113

The M113 engines, if regularly serviced and maintained, are generally very reliable and have few issues.

Regular oil changes are vital on the M113, particularly when the engine has been modified and is putting down more power than the manufacturer intended.

For more information on Tuning your M113 engine please join us in our friendly forum where you can discuss tuning options in more detail with our M113 owners. It would also be worth reading our unbiased tuning articles to get a full grasp of the benefits and drawbacks of each modification.

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We really like hearing from our readers, and hearing about which parts were the most effective for them, it helps us improve our recommendations and articles to reflect current trends in modifications and ensures that our M113 guides and tips are kept up to date.

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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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