Tuning the Mazda SkyActiv-D

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

We are frequently getting emails asking how to improve the SkyActiv-D from people wanting to know what are the best tips on SkyActiv-D modifications. So let us look into Mazda SkyActiv-D tuning mods and outline the best modifications on this great engine and point out some common pitfalls along the way.

Here we detail the best approach to SkyActiv-D tuning and provide tips on the optimum upgrades. Mazda SkyActiv-D are fantastic to work on and with the right motorsport mods like remaps, turbo improvements and camshafts you will really maximize your driving pleasure.

Just because particular mods are popular with SkyActiv-D owners it doesn't mean it is good, we shall best mods that will give your SkyActiv-D the best power gain for you money.

Altering your SkyActiv-D camshaft will make a dramatic difference to the engine torque. Choosing a higher performance camshaft profile raises the torque accordingly.

NB: Fast road cams tend to bump the power throughout the rev band, you could sacrifice a little low end power but top end will be lifted.

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

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

You should ideally match your torque band to your cars usage so for a car driven daily stick with a shorter duration SkyActiv-D camshaft

Different SkyActiv-D engines respond better to mild camshaft durations so set your engine up on a rolling road.

The ECU mapping and fuelling also will say much on the bhp gains you'll make.

Altering 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.

SkyActiv-D Tuning Stages

Stage 1 SkyActiv-D modifications: Drilled & smoothed airbox, Sports exhaust manifold, Panel air filters, Remaps/piggy back ECU, Fast road camshaft, Intake headers.

Stage 2 SkyActiv-D modifications: induction kit, Fast road cam, fuel pump upgrades, Sports catalyst & performance exhaust, high flow fuel injectors, Ported and polished head.

Stage 3 SkyActiv-D modifications: 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, Engine balancing & blueprinting, Competition cam.

Remaps will help to establish the full potential of all the upgrades you've done to your SkyActiv-D.

It will usually give around 30% more power on turbocharged vehicles and you can expect to see around 15% on NASP engines, but the outcome usually depend much on the upgrades you've done and the condition of your engine.

It is the whole point to any engine tuning project to force fuel and air into the SkyActiv-D engine

Air Intake manifolds flow the air from the intake filter and allow it to be drawn into the engine cylinders with fuel for the squish phase.

The size of bore and shape and flow characteristics of the Plenum can make a noticeable change to fuel atomisation on the SkyActiv-D.

Commonly we find the intake manifold are needing an upgrade, although a few manufacturers provide reasonably good intake manifold.

Adding a SkyActiv-D larger valve kit, carrying out SkyActiv-D port enlargement and head flowing will also raise performance, and importantly will make space for raising the performance increase on other upgrades.

Turbo upgrades for the SkyActiv-D

NASP engines need quite a lot of work when you add a turbo, so we have a separate guide to help you take into account the pros and cons of going this route on your 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 excellent power gains.

When a car has forced induction tuning mods are simpler to install and you'll see that turbocharged engines are made with strengthened components.

However you'll find engines have limits

It is important to find these limits and upgrade to better quality components to utilize the power.

We've seen car owners spending a lots of money on turbo upgrades on the SkyActiv-D only to experience the SkyActiv-D literally blow up on it's first outing after it's finished.

Big turbos tend to experience low end lag, and smaller turbos spool up much more quickly but do not have the high rpm torque gains.

We are pleased that the choice of turbo chargers is always improving and we now see variable vane turbo chargers, allowing the vane angle is altered according to speed to lower lag and increase top end power.

Twin scroll turbo chargers divert the exhaust flow into a couple of channels and flow these at differently angled vanes in the turbo charger. They also help the scavenging effect of the engine.

It is not unusual that there is a limit in the air flow sensor AFM/MAP on the SkyActiv-D when considerably more air is being pulled into the engine.

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

Adding a supercharger or additional turbo will make large torque gains, although harder to configure. We have this feature on twinchargers if you want to read more.

Uprating SkyActiv-D fuel injectors

When you lift the performance you will need to increase to the fuel delivery.

More performance needs more fuel. We would recommend you to over specify your injectors flow rate.

The rule of thumb is to add 20% when fitting an injector, this allows for injector deterioration and allows a bit of spare capacity should the engine need more fuel.

We think this one is common sense, but you'll need to match your fuel injector to the type of fuel your car uses as well.

Best SkyActiv-D performance exhausts

You only need to to improve your exhaust if your current exhaust is actually creating a restriction.

On most factory exhausts you should find that the exhaust flow rate is still ok even on modest power gains, but when you start pushing up the power levels you will 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 2.5 inches bore, you will lose much of the flow rate and end up lacking power and torque.

Typically exhaust restrictions can be traced to the catalyst installed, so adding a faster flowing sports alternative will help avoid this restriction.

Problems and issues to look out for on the SkyActiv-D

The SkyActiv-D engines, if regularly serviced and maintained, are generally very reliable and have few issues.

Regular oil changes are vital on the SkyActiv-D, particularly when the engine has been modified and is putting down more power than the manufacturer intended.

For more information on Tuning your SkyActiv-D engine please join us in our friendly forum where you can discuss tuning options in more detail with our SkyActiv-D owners. It would also be worth reading our unbiased tuning articles to get a full grasp of the benefits and drawbacks of each modification.

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This article is flagged for an update, so please pass on specific tips below that I can include. All articles, and content was written by me, Waynne Smith TorqueCars founder. Some outlines are just too general so I appreciate your feedback and suggestions. This entry was filed under Mazda. You can leave a response below or join our forum to discuss this article and car modification in detail with our members.

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