Modding upgrading and tuning the Renault M4R engine!

Car tuning tips:M4R Modifications"

How to modify and upgrade the Renault M4R

"Comprehensive guide to tuning the Renault M4R engine!"

Popular tuning sites like TorqueCars are always seeing threads about how to improve the M4R from people inquiring about getting more power from the M4R and wanting to know what are the optimum M4R power upgrades. So let us look into Renault M4R parts and outline the best mods that work on this great engine and point out some potential pitfalls along the way.

We shall consider M4R tuning and report on the premier mods that work. Renault M4R are popular engines and with the optimum motorsport upgrades like remapping, turbo kits and camshafts you will substantially increase your driving opportunities.

The greatest M4R parts on an engine are usually the ones that give the best gains for your money.

We won't be swayed by popular M4R parts, they need to be cost effective.

M4R induction kits

Improving air intake on the M4R

You need fuel and air for an engine to work. If there is insufficient fuel then it will run lean, if there is not enough air it runs rich resulting in lost power and potentially damaging the engine. We'll pick up on fuelling later in this article but for now we shall look at air supply.

So Forcing more air and fuel into each cylinder is the whole point to any car tuning job.

It is not unusual that there's a limitation in the air flow sensor AFM/MAF on the M4R when considerably more air is being drawn into the engine.

When tuning you may well find you need to get an air sensor or flow meter capable of upto 4 bars to cope with quite large power gains, whereas the OEM air sensor was restricting power at a much lower level.

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

Design and rate of flow of the Intake headers can make a noticeable improvement to fuel atomisation on the M4R.

Commonly we find the air intake manifolds are in desperate need of a performance upgrade, although some makers provide fairly well optimized air intake manifolds.

Larger M4R valves, getting 3 or 5 angle valve jobs and porting and head flowing will also boost power, & importantly will give you a better power increase on other tuning mods.

M4R performance cam tips.

Some M4R engines respond better to mild camshaft durations check your engine on a rolling road.

The engine timing and injectors and fuel pump also have a large bearing on the bhp gains you'll get.

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 M4R 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 commonly increase the torque through the rpm range, you may lose a little low end torque but higher rpm power will be higher.

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

On a car driven daily you need to optimize your bhp range to your driving style.

I would be surprised if you have found a M4R Motorsport cam is a pleasure to live with when on the daily commute.

Stage 1, 2 and 3 mods for the M4R

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 M4R parts:

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

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

Stage 2 M4R parts:

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

Stage 3 M4R parts:

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

Plan your options and then buy your parts and set yourself a power target to avoid costly mistakes.

A remap helps to establish the full potential of all the parts you've done to your M4R.

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 usually differs on the parts you've carried out and the condition of your engine.

Turbo modifications on the M4R

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 M4R.

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 an engine has a turbocharger tuning parts are going to make more power and most turbo charged engines will have harder and stronger components.

However every engines will have power limits

Research these restrictions and upgrade to better pistons and crank to utilize the power.

There are many guys spending a a stack of money on turbo charger upgrades on the M4R only to see the engine block literally blow up just after it's used on the roads.

Large capacity turbo chargers tend to experience no power at low rpm, and little turbo chargers spool up more quickly but do not have the peak end torque gains.

Thankfully the market of turbo chargers is always increasing and we commonly find variable vane turbo chargers, allowing the vane profile is altered according to speed to lower lag and increase top end bhp.

Twin scroll turbo chargers divert the exhaust gases into 2 channels and push these at differently designed 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 torque gains, although more difficult to install. We have this article on twincharging if you want to read more.

Tips about fuel supply on the M4R

Don't overlook the need to uprate the fuelling when you are increasing the performance - it makes the car more thirsty. Experienced tuners recommend to over specify your injector capacity.

The accepted safe increase is to add 20% when buying an injector, this takes into account injector deterioration and gives a bit of 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 M4R performance exhaust upgrades

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

On most factory exhausts you'll find your flow rate is still 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 generally help improve air flow through the engine but avoid an exhaust that is too wide or you may end up will reduce the flow rate. Stick to one and a half to two and half inches as a rule of thumb.

Usual exhaust restrictions can be traced to the emissions filters installed, so adding a higher flowing sports 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 M4R

Like most engines an M4R, 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 M4R, failure to do this will exacerbate engine wear, on a tuned M4R 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 M4R why not pop over to the forums at TorqueCars where you can chat about M4R tuning options and read about others projects who may be planning to do similar modifications on their M4R.

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