Modding uprating the Mazda SkyActiv-D engine!

Discover "SkyActiv-D Modifications"

How to modify and upgrade the Mazda SkyActiv-D

"Comprehensive guide to tuning the Mazda SkyActiv-D engine!"

Sites like TorqueCars are frequently getting messages asking how to improve the SkyActiv-D from people inquiring about getting more power from the SkyActiv-D and wanting to know what are the best tips for SkyActiv-D power upgrades. So let us look into Mazda SkyActiv-D tuning mods and outline the best modifications on this great engine and point out some potential pitfalls along the way.

Now we shall look into SkyActiv-D tuning and outline the premier mods that work. Mazda SkyActiv-D are good project engines and with carefully picked motorsport upgrades like ECU maps, turbo upgrades and camshafts you will greatly enhance your driving experience.

The ultimate SkyActiv-D upgrades on an engine are as we have found the ones that give the best power gain for your hard earned cash.

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

SkyActiv-D induction kits

Improving air intake on the SkyActiv-D

You need fuel and air for an engine to work. If there is insufficient fuel then it will run lean, if there is a lack of 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 Pulling air and fuel into the SkyActiv-D engine is vital to any engine modification job.

You'll commonly see there's a restriction in the air flow sensor (AFM/MAF/MAP) on the SkyActiv-D when a lot more air is being fed into the engine.

We see 4 bar air sensors coping with quite large power gains, whereas the OEM air sensor sapped power at a much lower level.

Intake headers take the air from the air filter and allow it to be drawn into the engine and mixed with fuel.

The size of bore and shape and rate of flow of the Headers can make a big difference to to fuel engine efficiency on the SkyActiv-D.

I usually find intake manifold are in dire need of an upgrade, although a few car makers provide reasonably well designed intake manifold.

Larger SkyActiv-D valves, doing a bit of port work and head flowing will also lift performance, & more importantly will permit an improved performance increase on other upgrades.

SkyActiv-D performance cam tips.

Some SkyActiv-D engines even from the same production line will vary with some working better on different setups or needing less aggressive camshaft durations, but porting and flowing the head should reduce the differences and give consistent results.

The ecu map and injectors and fuel pump also will say much on the torque gains you'll get.

Extending exhaust or intake durations can alter the torque 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 SkyActiv-D 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 raise the bhp and torque over the rev band, you may lose a little low down power but the top end will be higher.

Competition cams, raise the top end band but as a result the car will not idle smoothly and low end power nearly always suffers.

A Motorsport and race camshaft will just annoy you whilst driving in heavy traffic.

You should ideally match your torque band to your preferences so for a car used daily stick with a mild fast road SkyActiv-D camshaft

Stage 1, 2 and 3 mods for the SkyActiv-D

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 SkyActiv-D parts:

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

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

Stage 2 SkyActiv-D parts:

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

Stage 3 SkyActiv-D parts:

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

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

Remapping should help to release the full potential of all the mods you've done to your SkyActiv-D.

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 will vary depending on the mods you've fitted and the condition of your engine.

Turbo modifications on the SkyActiv-D

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 SkyActiv-D.

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

If an engine is turbocharged, parts are going to make more power and you'll see that turbo charged engines are built using strengthened components.

However you'll find engines have weakspots

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

It's not unheard of guys spending a fortune on turbo upgrades on the SkyActiv-D only to suffer the humiliation of seeing the whole thing explode on it's first outing after it's used on the roads.

Bigger upgraded turbos will usually experience a bottom end lag, and little turbos spool up more quickly but won't have the peak rpm engines power gains.

Thanks to progress the market of turbos is always increasing and we commonly find variable vane turbos, allowing the vane angle is altered according to speed to lower lag and increase top end torque.

Twin scroll turbos divert the exhaust gases into a couple of channels and direct these at differently angled 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 challenging to get working. We have this article covering twinchargers if you want to read more.

Tips about fuel supply on the SkyActiv-D

When you lift the bhp and torque you will need to pay attention to to the fuel system.

More bhp and torque needs more fuel. Don't forget to be generous with your injector capacity.

The accepted safe increase is to add 15% when buying an injector, this accounts for injector deterioration and gives 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 SkyActiv-D performance exhaust upgrades

The only time you should look to replace 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 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 balance the flow of air through the engine.

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

Usual exhaust restrictions come around the emissions filters installed, so adding a faster flowing race alternative will help avoid this restriction.

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

Faults issues and things to look out for on the SkyActiv-D

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

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