Modding tuning and best performance upgrades on the Mercedes M133 engine!

Tuners tips on "M133 Modifications"

M133 Modifications Guide

How to modify and upgrade the Mercedes M133

"Comprehensive guide to tuning the Mercedes M133 engine!"

Forums like the one at TorqueCars are always getting posts asking about how to improve the M133 from people wanting to know what are the ultimate M133 upgrades. So let us look into Mercedes M133 upgrades and outline the best modifications on this great engine and point out some common pitfalls along the way.

The Mercedes M133 really good project engines and with carefully chosen modified upgrades like ECU maps, turbo kits and camshafts you will definitely maximize your driving enjoyment.

Let us examine the options for your M133 tuning and provide tips on the premier modifications for your car.

The best M133 mods on an engine are obviously the ones that give the biggest return for your money.

We won't be swayed by popular M133 mods, they need to be cost effective.

M133 induction kits

Improving air intake on the M133

You need air matched to fuel for an engine to work. If there is little supply of fuel then it will run lean, if there is a lack of air it runs rich losing power which risks damage to the M133. We'll pick up on fuelling later in this article but for now we shall look at air supply.

So Forcing fuel and air into the M133 engine is the primary aim to any tuning project.

It is not unusual that there is a limitation in the air flow sensor MAF/MAP on the M133 when considerably 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 was restricting performance at a much lower level.

Air Intake manifolds flow the during the engines suck phase from the filter and allow it to be drawn into the engine cylinders.

The shape and flow characteristics of the Intake headers can make a substantial effect on to fuel atomisation on the M133.

Most intake headers are needing performance upgrades, although a few makers provide fairly well optimized intake headers.

Increasing the M133 valve size, doing some 3 or 5 angle valve jobs and porting and head flowing will also increase power, and as an added benefit will permit increasing the power increase on other upgrades.

M133 performance cam tips.

Different M133 engines respond better to mild camshaft durations so view each engine as unique.

The map and injectors and fuel pump also have a large bearing 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.

The camshaft profile plays a big part in the engines power output so camshaft upgrades make quite a large difference. The intake & exhaust durations will alter depending on the chosen camshaft profile, so large bhp gains are on offer for camshaft upgrades.

NB: Fast road cams usually bump the power over the rpm range, you could sacrifice a little low end power but higher rpm power will be better.

Motorsport cams, bump the higher rpm power band but as a result the car will not idle smoothly and low end power nearly always suffers.

For a typical daily driver you need to match your engines power to your typical driving style.

I'd be surprised if you find a M133 Race cam is a pleasure to live with when driving in heavy traffic.

Stage 1, 2 and 3 mods for the M133

Stage 1 M133 parts:

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

Stage 2 M133 parts:

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

Stage 3 M133 parts:

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

The M133 units respond well to mods and we note that there is an increase of mods and performance parts out there.

Remapping helps unlock the full potential of all the mods you've done to your M133.

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

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 may rely on the mods you've fitted and the condition of your engine.

Turbo modifications on the M133

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 M133.

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.

If your car has forced induction tuning parts are relatively easy and turbo charged engines are built using strengthened components.

However most engines have limits

Research these restrictions and upgrade to higher quality components to handle the power.

There are many guys spending a loads of money on turbo charger upgrades on the M133 only to watch the engine block literally blow up just after it's completed.

Larger turbo chargers commonly experience low end lag, and low capacity turbo chargers spool up much more quickly but don't have the top end torque gains.

Thankfully the world of turbos is always moving on and we now see variable vane turbos, where the vane angle is altered according to speed to lower lag and increase top end power.

Twin scroll turbos divert the exhaust flow into 2 channels and feed these at differently designed vanes in the turbo. 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 power gains, although more complex to install. We have this feature on twinchargers if you want to read more.

Tips about fuel supply on the M133

Don't overlook the need to improve the fuelling when you are increasing the performance - it makes the car more thirsty. Care modifiers usually say to over specify your flow rate on the injectors.

The accepted safe increase is to add 15% to the flow rate when fitting an injector, this accounts for injector deterioration and provides 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 M133 performance exhaust upgrades

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

On most factory exhausts you'll find the 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.

Do not go with the widest exhaust you can source you'll reduce the exhaust flow rate - the best 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.

The usual suspects causing problems in your exhaust flow rate can be traced to the filters installed, so adding a freer flowing performance alternative will help avoid this restriction.

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

Faults issues and things to look out for on the M133

Like most engines an M133, 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 M133, failure to do this will exacerbate engine wear, on a tuned M133 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 M133 why not pop over to the forums at TorqueCars where you can chat about M133 tuning options and read about others projects who may be planning to do similar modifications on their M133.

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