Everything You Need To Know About "M113 Modifications"

How to modify and upgrade the Mercedes M113

"Comprehensive guide to tuning the Mercedes M113 engine!"

Forums like the one at TorqueCars often are getting messages requesting information on how to improve the M113 from people wanting to know what are the best M113 upgrades. So let us look into Mercedes M113 tuning mods and outline the best upgrades on this great engine and point out some frequent tuning mistakes along the way.

The Mercedes M113 have loads of potential and with carefully picked sports parts like a remap, turbo kits and camshafts you will positively improve your driving enjoyment.

In this article we outline options for your M113 tuning and highlight the ultimate mods that work.

When talking about the top parts for your M113 engine, we are going to concentrate on the tuning parts that give the best value for money.

Improving air intake on the M113

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 a lack 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 the aim to any engine modification project to pull more air into each cylinder but this has a knock on effect with the air flow sensor.

It is common that there's a limit in the air flow sensor MAP/MAF/AFM on the M113 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 bhp at a much lower level.

Intake take 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 manifold can make a big improvement to fuel engine efficiency on the M113.

Commonly we find the air intake manifolds are begging for an upgrade, although some manufacturers provide reasonably well designed air intake manifolds.

Increasing the M113 valve size, doing a bit of port matching and head flowing will also increase torque, & importantly will raise potential for a better torque increase on other mods.

M113 performance cam tips.

Some M113 engines respond better to more or less aggressive cam durations so view each engine as unique.

The ECU mapping and fuel pump and injectors also will say much on the bhp gains you'll get.

A longer valve duration 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.

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

NB: Fast road cams commonly push up the torque throughout the rev range, you might lose a little low end bhp but the top end will be higher.

Motorsport cams, push up the top end band but as a result the car will not idle smoothly and low end power nearly always suffers.

A Race cam makes it harder when in heavy traffic.

You should ideally match your power band to your cars usage so for a typical daily driver stick with a mild fast road M113 cam

Stage 1, 2 and 3 mods for the M113

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 M113 parts:

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

Stage 2 M113 parts:

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

Stage 3 M113 parts:

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

Remapping allows a tuner to unlock the full potential of all the tuning parts you've done to your M113.

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 your results will vary depending on the tuning parts you've carried out and the condition of your engine.

Turbo modifications on the M113

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 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 excellent power gains.

When the engine has forced induction tuning mods are going to make more power and you'll see that turbo engines already contain strengthened components.

There are common areas of failure for every engine, with some being incredibly solid and some only just able to handle stock power

Discover these restrictions and fit forged components to survive the power.

We see many drivers spending a a stack of money on turbo upgrades on the M113 only to suffer the humiliation of seeing the M113 literally blow up soon after it's been enthusiastically driven.

Larger capacity turbochargers will usually experience a bottom end lag, and little turbochargers spool up more quickly but do not have the top end torque gains.

We are pleased that the selection of turbo units is always moving on and we are seeing variable vane turbo units, allowing the vane profile is altered according to speed to lower lag and increase top end performance.

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

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

Tips about fuel supply on the M113

Don't miss you'll need to uprate the fuel delivery when you are increasing the torque - it makes the car more thirsty. Don't forget to be generous with your flow rate on the injectors.

As a rule of thumb add another 20% when fitting an injector, this accounts for injector deterioration and allows 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 M113 performance exhaust upgrades

You should look to uprate your exhaust system with an upgraded one is if your current exhaust is creating a flow problem.

On most factory exhausts you'll see 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 equal out the flow of air through the engine.

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

The usual suspects causing problems in your exhaust flow rate are in the filters installed, so adding a higher flowing sports alternative will help avoid this restriction.

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

Faults issues and things to look out for on the M113

Like most engines an M113, 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 M113, failure to do this will exacerbate engine wear, on a tuned M113 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 M113 why not pop over to the forums at TorqueCars where you can chat about M113 tuning options and read about others projects who may be planning to do similar modifications on their M113.

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This entry was posted under Makes and Models. Tags: engine, mercedes
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