Modding upgrading and tuning the Nissan RB20DET engine!

Tuners tips on "RB20DET Modifications"

How to modify and upgrade the Nissan RB20DET

"Comprehensive guide to performance parts and tuning the Nissan RB20DET engine!"

Forums like the one at TorqueCars are always getting emails asking about how to improve the RB20DET from people inquiring about getting more power from the RB20DET and wanting to know what are the things tuners recommend when it comes to RB20DET upgrades. So let us look into Nissan RB20DET modifications and outline the best modifications on this great engine and point out some potential pitfalls along the way.

Car Tuning Tips will consider RB20DET tuning and show the ultimate upgrades. Nissan RB20DET are good project engines and with the ultimate parts like a remap, turbo upgrades and camshafts you will greatly improve your driving opportunities.

Just because particular tuning mods are are common on RB20DET it doesn't mean its worth having, instead we will focus on the ultimate tuning mods that will give your RB20DET the best power gain for you spend.

Without us subscribing to the common myth of 'if it's shiny and makes more noise it must be good' you seem to get in many tuning magazines and on car forums'.

RB20DET induction kits

Improving air intake on the RB20DET

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

So the primary aim to any engine upgrade job to feed more air into the RB20DET engine 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 AFM/MAP on the RB20DET when considerably more air is being sucked 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.

Intake headers transmit the air during the suck phase from the filter and allow it to be pulled into the engine cylinders with fuel for the squish phase.

Design and flow rate of the Headers can make a substantial change to fuel mixing and power on the RB20DET.

We often see intake manifold are in dire need of a performance upgrade, although a few makers provide reasonably well designed intake manifold.

Fitting big valve kits, getting port work and head flowing will also increase bhp and torque, and importantly will allow you to get a greater bhp and torque increase on other upgrades.

RB20DET performance cam tips.

Each engine responds better to more or less aggressive camshaft durations so set your engine up on a rolling road.

The map and fuel pump and injectors also will say much on the power gains you'll achieve.

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.

Altering your RB20DET camshaft will make a dramatic difference to the engine engines power. Choosing a higher performance camshaft profile raises the engines power accordingly.

NB: Fast road camshafts tend to push up the torque through the rpm range, you could sacrifice a little low end power but the higher rpm power will improve.

Competition camshafts, push up the higher rpm power band but as a result the car will not idle smoothly and low end power nearly always suffers.

A Motorsport and race camshaft is not great driving around busy urban areas.

You should ideally optimize your power band to your driving style so for a road car stick with a mild fast road RB20DET camshaft

Stage 1, 2 and 3 mods for the RB20DET

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 RB20DET parts:

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

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

Stage 2 RB20DET parts:

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

Stage 3 RB20DET parts:

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

The RB20DET power trains respond well to mods and thanks to their popularity there is a growing number of mods and performance parts around.

Remaps will help release the full potential of all the modifications you've done to your RB20DET.

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 the end result often rely on the modifications you've fitted and the condition of your engine.

Turbo modifications on the RB20DET

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 RB20DET.

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.

If the engine has forced induction upgrades are going to net you a larger power gain and you'll see that turbocharged engines are built with stronger components.

There are tuning limits for every engine, with some being over specified and some only able to handle stock power

Discover these limitations and install higher quality components to cope with the power.

There are many people spending a loads on turbo upgrades on the RB20DET only to suffer the indignity of watching the engine block explode just after it's been completed.

Bigger turbo chargers tend to experience no power at low rpm, and smaller turbo chargers spool up more quickly but don't have the peak end bhp gains.

We are pleased that the range of turbo units is always developing and we are seeing variable vane turbo units, permitting the vane profile is altered according to speed to lower lag and increase top end bhp and torque.

Twin scroll turbo units divert the exhaust gases 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 torque gains, although more complex to get working. We have this feature on twinchargers if you want to read more.

Tips about fuel supply on the RB20DET

Don't overlook the need to pay attention to the fuel delivery when you are increasing the performance - it makes the car more thirsty. It is important to over specify your flow rate on the injectors.

The accepted safe increase is to add 15% to the flow rate when specifying an injector, this allows for injector deterioration and gives 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 RB20DET performance exhaust upgrades

We'd only recommend you look to upgrade your exhaust system with an upgraded one is if the existing exhaust is actually creating a restriction in flow.

On most factory exhausts you'll find the exhaust flow rate is good 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 can help increase the flow of air through the engine.

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

Usual exhaust restrictions come around the catalyst and filters installed, so adding a higher flowing race 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 RB20DET

Like most engines an RB20DET, 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 RB20DET, failure to do this will exacerbate engine wear, on a tuned RB20DET 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 RB20DET why not pop over to the forums at TorqueCars where you can chat about RB20DET tuning options and read about others projects who may be planning to do similar modifications on their RB20DET.

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