Modding uprating the Nissan VK45DD engine!

All you need to know about "VK45DD Modifications"

How to modify and upgrade the Nissan VK45DD

"Comprehensive guide to tuning and performance parts on the Nissan VK45DD engine!"

TorqueCars are regularly getting messages requesting information on how to improve the VK45DD from people wanting to know what are the things tuners recommend when it comes to VK45DD power upgrades. So let us look into Nissan VK45DD mods and outline the best mods that work on this great engine and point out some potential pitfalls along the way.

The Nissan VK45DD are popular tuning projects and with the ultimate performance modifications like a remap, turbo upgrades and camshafts you will noticeably maximise your driving enjoyment.

Our aim here is to detail the best approach to VK45DD tuning and outline the optimum upgrades.

The best VK45DD upgrades on an engine are in our opinion the ones that give the best power gain for your hard earned cash.

We won't be swayed by popular VK45DD upgrades, they need to be cost effective.

VK45DD induction kits

Improving air intake on the VK45DD

You need air and fuel for an engine to work. If there is little supply of fuel then it will run lean, if there is too little air it runs rich resulting in lost power . We'll pick up on fuelling later in this article but for now we shall look at air supply.

So the aim to any performance tuning task to feed air into each cylinder but this has a knock on effect with the air flow sensor.

It is not unusual that there is a limit in the air flow sensor (AFM/MAF/MAP) on the VK45DD when loads more air is being fed into the engine.

We note 4 bar air sensors coping with quite large power gains, whereas the OEM air sensor was restricting bhp at a much lower level.

Engine intake manifolds transmit the during the engines suck phase from the filter and allow it to be pulled into the engine cylinders.

The size of bore and shape and flow characteristics of the Intake headers can make a substantial difference to to fuel mixing and power on the VK45DD.

On popular production engines intake headers are needing performance upgrades, although a few OEM provide decently flowing intake headers.

Larger VK45DD valves, doing some 3 or 5 angle valve jobs and porting and head flowing will also lift bhp, and as an added benefit will make space for a greater bhp increase on other mods.

VK45DD performance cam tips.

Different VK45DD engines respond better to more aggressive cam durations check your engine on a rolling road.

The ECU mapping and injectors and fuel pump also have an effect on the bhp gains you'll make.

Longer 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.

Altering your VK45DD 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 cams usually boost the power through the rpm band, you may lose a little low down bhp but the higher rpm power will be higher.

Race cams, boost 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 makes it harder when on the daily commute.

You should ideally match your torque band to your usage of the car so for a car driven daily stick with a fast road VK45DD camshaft

Stage 1, 2 and 3 mods for the VK45DD

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 VK45DD parts:

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

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

Stage 2 VK45DD parts:

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

Stage 3 VK45DD parts:

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

Carefully think through your options and then source your parts and set yourself a power target to avoid wasting your time and money.

ECU flashing allows a tuner to to establish the full potential of all the tuning mods you've done to your VK45DD.

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 figures achieved will rely on the tuning mods you've carried out and the condition of your engine.

Turbo modifications on the VK45DD

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 VK45DD.

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 your car has forced induction tuning parts are relatively easy and you'll see that turbo engines are built using uprated components.

However you will find an engines have limits

We recommend you find these limitations and fit higher quality components to handle the power.

We've seen mechanics spending a fortune on turbo upgrades on the VK45DD only to watch the car literally blow up just after it's finished.

Bigger capacity turbochargers tend to experience low end lag, and low capacity turbochargers spool up quickly but don't have the top end bhp gains.

In recent times the market of turbo units is always increasing and we are seeing variable vane turbo units, where the vane angle 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 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 bhp and torque gains, although more difficult to configure. We have this guide to twinchargers if you want to read more.

Tips about fuel supply on the VK45DD

Don't overlook the need to raise the fuel delivery when you are increasing the bhp and torque - it makes the car more thirsty. Most tuners we speak with say to be generous with your injectors flow rate.

The accepted safe increase is to add another 20% when specifying an injector, this accounts for injector deterioration and allows a little 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 VK45DD performance exhaust upgrades

You may need to boost your exhaust system with an upgraded one is if the current exhaust is actually creating a restriction in flow.

On most factory exhausts you'll see the flow rate is still 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 usually air flow through the engine but avoid an exhaust that is too large 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 located the catalyst installed, so adding a higher flowing sports alternative will help avoid this restriction.

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

Faults issues and things to look out for on the VK45DD

Like most engines an VK45DD, 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 VK45DD, failure to do this will exacerbate engine wear, on a tuned VK45DD 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 VK45DD why not pop over to the forums at TorqueCars where you can chat about VK45DD tuning options and read about others projects who may be planning to do similar modifications on their VK45DD.

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