Modding upgrading and tuning the Mazda SkyActiv-G engine!

Modifying and improving: "SkyActiv-G Modifications"

SkyActiv-G Modifications Guide

How to modify and upgrade the Mazda SkyActiv-G

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

TorqueCars are always getting posts requesting info on how to improve the SkyActiv-G from people wanting to know what are the premier SkyActiv-G modifications. So let us look into Mazda SkyActiv-G upgrades and outline the best modifications on this great engine and point out some common pitfalls along the way.

The Mazda SkyActiv-G are fantastic to work on and with the optimum tuning parts like a remap, turbo upgrades and camshafts you will dramatically maximize your driving pleasure.

This pages aim is look at SkyActiv-G tuning and outline the best modifications.

When talking about the ultimate parts for your SkyActiv-G engine, we are going to focus on the parts that give the best value for money.

SkyActiv-G induction kits

Improving air intake on the SkyActiv-G

You need air matched to fuel for an engine to work. If there is insufficient fuel then it will run lean, if there is insufficient air it runs rich resulting in lost power which risks damage to the SkyActiv-G. 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 performance tuning project to feed more fuel and air into the SkyActiv-G engine but this has a knock on effect with the air flow sensor.

It is common that there's a restriction in the air flow sensor AFM/MAP on the SkyActiv-G when a lot more air is being drawn into the engine.

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

Engines intake headers take the during the engines suck phase from the filter and allow it to be fed into the engine and mixed with fuel.

Structure and flow characteristics of the Air Intake manifolds can make a substantial difference to to fuel engine efficiency on the SkyActiv-G.

Commonly we find the intake manifold are crying out for an upgrade, although some makers provide reasonably well designed intake manifold.

Adding a SkyActiv-G larger valve kit, doing a bit of 3 or 5 angle valve jobs and porting and head flowing will also boost bhp and torque, and more importantly will allow you to get an improved bhp and torque increase on other mods.

SkyActiv-G performance cam tips.

Some SkyActiv-G engines respond better to extreme camshaft durations than others.

The ecu map and injectors and fuel pump also will make differences on the power gains you'll achieve.

A longer valve duration 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.

The camshaft profile plays a big part in the engines power output so camshaft upgrades make quite a large difference. The intake and exhaust durations will alter depending on the chosen camshaft profile, so large bhp gains are on offer for camshaft upgrades.

NB: Fast road camshafts usually boost the torque through the rev range, you may sacrifice a little low down bhp but high end rpm power will be lifted.

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

In a daily driver you need to match your engines power to your driving style.

I'd be amazed if you find a SkyActiv-G Motorsport and race camshaft is a pleasure to live with when driving around busy urban areas.

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

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-G parts:

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

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

Stage 2 SkyActiv-G parts:

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

Stage 3 SkyActiv-G parts:

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

The SkyActiv-G engines are great to work on and we note that there are plenty of mods and performance parts out there.

ECU mapping will help fully realize the full potential of all the upgrades you've done to your SkyActiv-G.

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 usually differs on the upgrades you've fitted and the condition of your engine.

Turbo modifications on the SkyActiv-G

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-G.

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

When your motor is turbo charged tuning parts are relatively easy and most turbocharged engines are built with strengthened components.

However you will find an engines will need better parts at higher power limits

Discover these limits and fit stronger pistons, crank and engine components to utilize the power.

It's not unheard of mechanics spending a loads on turbocharger upgrades on the SkyActiv-G only to watch the car explode just after it's used on the roads.

Larger turbochargers commonly experience a bottom end lag, and little turbochargers spool up really quickly but won't have the top end engines power gains.

In recent times the choice of turbo chargers is always moving on and we are seeing variable vane turbo chargers, allowing the vane profile is altered according to speed to lower lag and increase top end torque.

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

Beefing up the air intake by adding a supercharger or additional turbo will help you achieve very large power gains, although more challenging to install. We have this feature on twinchargers if you want to read more.

Tips about fuel supply on the SkyActiv-G

Don't omit to raise the fuelling when you are increasing the performance - it makes the car more thirsty. It is important to over specify your flow rate on the injectors.

As a rule of thumb add 20% to the flow rate when specifying an injector, this takes into account injector deterioration and provides you some spare capacity should the engine need 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-G performance exhaust upgrades

You should 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 flow rate is still fine 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 will certainly help air flow through the engine but avoid an exhaust that is too big 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.

The usual suspects causing problems in your exhaust flow rate are in the catalyst and filters installed, so adding a faster flowing high performance alternative will help avoid this restriction.

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

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

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

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