All you need to know about "M260 Modifications"

How to modify and upgrade the Mercedes M260

"Comprehensive guide to performance parts and tuning the Mercedes M260 engine!"

Forums like the one at TorqueCars often are getting posts requesting information on how to improve the M260 from people inquiring about getting more power from the M260 and wanting to know what are the things tuners are recommending when it comes to M260 power upgrades. So let us look into Mercedes M260 mods and outline the best modifications on this great engine and point out some common pitfalls along the way.

The Mercedes M260 are popular engines and with the right modified upgrades like a remap, turbo improvements and camshafts you will really maximise your driving fun.

Here we review M260 tuning and point out the best mods that work.

The best M260 parts on an engine are obviously the ones that give the best gains for your money.

We won't be swayed by popular M260 parts, they need to be cost effective.

Improving air intake on the M260

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

So Getting fuel and air into the M260 engine is the aim to any car tuning job.

You'll commonly see there is a limitation in the air flow sensor MAF/MAP on the M260 when considerably more air is being fed into the engine.

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

The intake plenum carry the during the engines suck phase from the filter and allow it to be sucked into the engine cylinders with fuel for the squish phase.

Design and flow rate of the Intake headers can make a substantial change to fuel atomisation on the M260.

I usually find air intake manifolds are in desperate need of performance upgrades, although some makers provide decently flowing air intake manifolds.

Larger M260 valves, carrying out port matching and head flowing will also raise power, and significantly will permit an improved power increase on other parts.

M260 performance cam tips.

Different M260 engines respond better to less aggressive camshaft durations check your engine on a rolling road.

The engine timing and fuel pump and injectors also have an effect on the bhp gains you'll hit.

Altering valve 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.

Significant air intake, and exhaust improvements on the M260 can be made from cam upgrades. Changing the cam profile alters the intake and exhaust durations on the engine and can dramatically change the engines power and power output.

NB: Fast road cams tend to push up the performance through the rpm range, you could sacrifice a little bottom end torque but the high end rpm power will improve.

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 Competition camshaft will just annoy you whilst driving in heavy traffic.

You should ideally optimize your engines power to your preferences so for a car used daily stick with a fast road M260 camshaft

Stage 1, 2 and 3 mods for the M260

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 M260 parts:

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

Stage 2 M260 parts:

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

Stage 3 M260 parts:

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

Remapping will help unlock the full potential of all the parts you've done to your M260.

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

Turbo modifications on the M260

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 M260.

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

When your motor is turbocharged, parts are simpler to install and most turbo charged engines use uprated components.

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

Discover these limits and install stronger pistons, crank and engine components to cope with the power.

We've seen people spending a lot of money on turbo upgrades on the M260 only to have the car go up in smoke on it's first outing after it's been enthusiastically driven.

Large turbo units commonly suffer a bottom end lag, and small turbo units spool up more quickly but don't have the high rpm engines power gains.

Thankfully the choice of turbos is always developing and we now see variable vane turbos, where the vane profile is altered according to speed to lower lag and increase top end bhp and torque.

Twin scroll turbos divert the exhaust flow into 2 channels and flow these at differently profiled vanes in the turbo charger. 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 performance gains, although more complex to configure. We have this article covering twinchargers if you want to read more.

Tips about fuel supply on the M260

Don't forget to look at the fuel system when you are increasing the bhp and torque - it makes the car more thirsty. We would recommend you to over specify your flow rate on the injectors.

The accepted safe increase is to add another 15% when specifying an injector, this accounts for injector deterioration and allows a bit of 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 M260 performance exhaust upgrades

Only look to increase your exhaust system with an upgraded one is if the current exhaust is creating a restriction.

On most factory exhausts you should find that the exhaust flow rate is 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.

Do not go with the largest exhaust you can source this will reduce the exhaust flow rate - the best exhausts for power gains are usually between one and a half to two and half inches. Your exhaust design, the bend angles and construction are what have more effect on flow rates than your pipe width to a certain extent. So the exhaust design is a big factor.

Typically exhaust restrictions are traced to the catalyst and filters 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 M260

Like most engines an M260, 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 M260, failure to do this will exacerbate engine wear, on a tuned M260 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 M260 why not pop over to the forums at TorqueCars where you can chat about M260 tuning options and read about others projects who may be planning to do similar modifications on their M260.

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