Modding uprating the Nissan MR20DE engine!

Discover "MR20DE Modifications"

How to modify and upgrade the Nissan MR20DE

"Comprehensive guide to tuning and performance parts on the Nissan MR20DE engine!"

Popular tuning sites like TorqueCars are frequently seeing threads requesting info on how to improve the MR20DE from people wanting to know what are the premier MR20DE upgrades. So let us look into Nissan MR20DE tuning mods and outline the best mods that work on this great engine and point out some problems along the way.

The Nissan MR20DE are popular tuning projects and with the optimum modified tuning mods like remaps, turbo upgrades and camshafts you will noticeably enhance your driving pleasure.

Let us look at MR20DE tuning and point out the best mods that work.

When talking about the best parts for your MR20DE engine, we are going to focus on the upgrades that give the best power gain for you money.

MR20DE induction kits

Improving air intake on the MR20DE

You need air matched to fuel for an engine to work. If there is too little fuel then it will run lean, if there is not enough air it runs rich losing 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 the fundamental goal to any engine upgrade task to pull more air into each cylinder but this has a knock on effect with the air flow sensor.

It is not unusual that there's a limitation in the air flow sensor AFM/MAF on the MR20DE when a lot more air is being pulled 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 limited power at a much lower level.

Engines intake headers transmit the on the suck phase from the filter and allow it to be drawn into the engine and mixed with fuel.

Design and rate of flow of the Intake headers can make a big effect on to fuel atomisation and engine efficiency on the MR20DE.

Commonly we find the intake manifold are needing motorsport parts, although a few car makers provide well optimised intake manifold.

Larger MR20DE valves, getting port work and head flowing will also increase bhp, and as an added benefit will permit a better bhp increase on other tuning parts.

MR20DE performance cam tips.

Each engine responds better to extreme cam durations so view each engine as unique.

The ECU mapping and fuelling also will make differences on the power gains you'll hit.

A longer valve duration 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.

Significant air intake, and exhaust improvements on the MR20DE can be made from camshaft upgrades. Changing the camshaft profile alters the intake and exhaust durations on the engine and can dramatically change the torque and power output.

NB: Fast road camshafts commonly bump the bhp and torque throughout the rpm band, you may lose a little low end torque but your high end rpm power will be higher.

Motorsport camshafts, bump the high end 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 power band to your typical driving style.

I'd never have ever thought a MR20DE Race cam is a pleasure to live with when driving in heavy traffic.

Stage 1, 2 and 3 mods for the MR20DE

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 MR20DE parts:

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

Stage 2 MR20DE parts:

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

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

Stage 3 MR20DE parts:

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

Review your options and then find your upgrades and set yourself a power target to avoid disappointment.

Remapping allows a tuner to fully realize the full potential of all the modifications you've done to your MR20DE.

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 often differs on the modifications you've applied and the condition of your engine.

Turbo modifications on the MR20DE

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 MR20DE.

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

When an engine is turbo charged tuning parts are simpler to install and most turbo charged engines are made with more solid components.

However you'll find engines will have power limits

Discover these limits and install better quality crank and pistons to utilize the power.

It's not unheard of mechanics spending a lots of money on turbo charger upgrades on the MR20DE only to suffer the indignity of watching the whole thing throw a rod soon after it's been enthusiastically driven.

Large capacity turbochargers tend to suffer low end lag, and small turbochargers spool up really quickly but do not have the top end engines power gains.

Thankfully the market of turbo units is always evolving and we are seeing variable vane turbo units, allowing the vane profile is altered according to speed to lower lag and increase top end bhp.

Twin scroll turbo units divert the exhaust gases into a couple of channels and feed these at differently profiled vanes in the turbo. 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 difficult to get working. We have this feature on twinchargers if you want to read more.

Tips about fuel supply on the MR20DE

Don't miss you'll need to increase the fuel system when you are increasing the power - it makes the car more thirsty. Experienced tuners recommend to be generous with your injectors flow rate.

The rule of thumb is to add 20% when fitting an injector, helps cope with injector deterioration and allows 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 MR20DE performance exhaust upgrades

You only need to to upgrade your exhaust system with an upgraded one is if your exhaust is actually creating a flow problem.

On most factory exhausts you should find that your flow rate is still 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 biggest exhaust you can source you'll slow the exhaust 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 are in the emissions filters installed, so adding a freer flowing high 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 MR20DE

Like most engines an MR20DE, 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 MR20DE, failure to do this will exacerbate engine wear, on a tuned MR20DE 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 MR20DE why not pop over to the forums at TorqueCars where you can chat about MR20DE tuning options and read about others projects who may be planning to do similar modifications on their MR20DE.

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