Modding and performance tuning parts for the Nissan HR12DDR engine!

Tuning guide "HR12DDR Modifications"

HR12DDR Modifications Guide

How to modify and upgrade the Nissan HR12DDR

"Comprehensive guide to tuning the Nissan HR12DDR engine!"

Popular tuning sites like TorqueCars are frequently seeing threads requesting information on how to improve the HR12DDR from people wanting to know what are the things tuners recommend when it comes to HR12DDR mods that work. So let us look into Nissan HR12DDR modifications and outline the best upgrades on this great engine and point out some frequent tuning mistakes along the way.

In this article we consider HR12DDR tuning and report on the greatest modifications. Nissan HR12DDR offer good returns when tuned and with a few sensible motorsport modifications like remapping, turbo kits and camshafts you will dramatically maximise your driving enjoyment.

The best HR12DDR tuning mods on an engine are as we have found the ones that give the best gains for your money.

We won't be swayed by popular HR12DDR tuning mods, they need to be cost effective.

HR12DDR induction kits

Improving air intake on the HR12DDR

You need fuel and air for an engine to work. If there is a lack of fuel then it will run lean, if there is too little 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 Shoving more air and fuel into your HR12DDR is the aim to any car tuning job.

You'll commonly see there's a limitation in the air flow sensor MAP/MAF/AFM on the HR12DDR when a lot 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 limited power at a much lower level.

Headers flow the during the engines suck phase from the intake filter and allow it to be fed into the engine cylinders.

Structure and rate of flow of the Plenum can make a substantial improvement to fuel atomisation and engine efficiency on the HR12DDR.

We often see headers are in dire need of a performance upgrade, although some OEM provide reasonably good headers.

Adding a HR12DDR larger valve kit, carrying out port matching and head flowing will also improve bhp, and more importantly will permit raising the bhp increase on other modifications.

HR12DDR performance cam tips.

Each engine responds better to more or less aggressive camshaft durations than others.

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

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.

Significant air intake, and exhaust improvements on the HR12DDR 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 normally increase the performance across the rpm band, you may lose a little low down bhp but your higher rpm power will be lifted.

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

In a car used daily you need to optimize your torque band to your cars usage.

I would be surprised if you find a HR12DDR Motorsport and race cam is a pleasure to live with when in heavy traffic.

Stage 1, 2 and 3 mods for the HR12DDR

Stage 1 HR12DDR parts:

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

Stage 2 HR12DDR parts:

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

Stage 3 HR12DDR parts:

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

The HR12DDR power plant respond well to mods and thanks to their popularity there is a growing number of modifications and performance parts out there.

Remapping allows a tuner to fully realize the full potential of all the tuning parts you've done to your HR12DDR.

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 mileage will depend much on the tuning parts you've fitted and the condition of your engine.

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

Turbo modifications on the HR12DDR

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 HR12DDR.

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

When a car has forced induction upgrades are simpler to install and most turbo charged engines are built with more solid components.

There are common areas of failure for every engine, with some being incredibly solid and some only just able to handle stock power

See where you'll find these limitations and fit better quality crank and pistons to survive the power.

It's not unheard of people spending a loads of money on turbocharger upgrades on the HR12DDR only to see the engine catastrophically fail soon after it's been finished.

Large capacity turbos tend to suffer a bottom end lag, and little turbos spool up quickly but won't have the peak end torque gains.

Thanks to progress the world of turbos is always moving on and we commonly find variable vane turbos, allowing the vane profile is altered according to speed to lower lag and increase top end power.

Twin scroll turbos divert the exhaust gases into 2 channels and direct these at differently designed vanes in the turbocharger. They also boost 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 challenging to configure. We have this guide to twinchargers if you want to read more.

Tips about fuel supply on the HR12DDR

Don't dismiss the need ramp up the fuelling when you are increasing the bhp and torque - it makes the car more thirsty. We would recommend you to be generous with your injectors flow rate.

As a rule of thumb add 20% when buying an injector, this allows for injector deterioration and gives 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 HR12DDR performance exhaust upgrades

The only time you should look to improve your exhaust system with an upgraded one is if the existing exhaust is actually creating a restriction.

On most factory exhausts you'll see the 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.

Sports exhausts can help equal out the flow of air through the engine.

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

Usual exhaust restrictions can be traced to the emissions filters installed, so adding a higher flowing high performance alternative will help avoid this restriction.

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

Faults issues and things to look out for on the HR12DDR

Like most engines an HR12DDR, 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 HR12DDR, failure to do this will exacerbate engine wear, on a tuned HR12DDR 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 HR12DDR why not pop over to the forums at TorqueCars where you can chat about HR12DDR tuning options and read about others projects who may be planning to do similar modifications on their HR12DDR.

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