Modding and performance tuning parts for the Suzuki K series K12 engine!

Tuning guide "K series K12 Modifications"

K series K12 Modifications Guide

How to modify and upgrade the Suzuki K series K12

"Comprehensive guide to tuning the Suzuki K series K12 engine!"

Our friends at TorqueCars often are getting posts requesting info on how to improve the K series K12 from people wanting to know what are the best tips on K series K12 modifications. So let us look into Suzuki K series K12 mods and outline the best mods that work on this great engine and point out some frequent tuning mistakes along the way.

Here we consider K series K12 tuning and provide tips on the ultimate modifications for your car. Suzuki K series K12 make a good tuning project and with the best sports parts like remaps, turbo kits and camshafts you will noticeably improve your driving opportunities.

Just because particular upgrades are appear in lots of K series K12 projects it doesn't mean its worth having, instead we'll concentrate on the top upgrades that will give your K series K12 the biggest power gain return for your cash.

Without us subscribing to the misaprehension of 'if it's shiny and makes more noise it must be good' you seem to get in many tuning magazines and on car forums'.

K series K12 induction kits

Improving air intake on the K series K12

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 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 the primary aim to any engine tuning project to get air into each cylinder but this has a knock on effect with the air flow sensor.

You'll commonly see there's a restriction in the air flow sensor (AFM/MAF/MAP) on the K series K12 when considerably more air is being pulled into the engine.

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

The intake plenum take the during the engines suck phase from the air cleaner and allow it to be drawn into the engine and mixed with fuel.

The bore size, shape and rate of flow of the Headers can make a substantial improvement to fuel atomisation and engine efficiency on the K series K12.

On popular production engines intake manifold are ripe for aftermarket parts, although a few car makers provide fairly well optimized intake manifold.

Larger K series K12 valves, carrying out 3 or 5 angle valve jobs and porting and head flowing will also boost bhp and torque, this will raise potential for an improved bhp and torque increase on other upgrades.

K series K12 performance cam tips.

Some K series K12 engines respond better to mild cam durations check your engine on a rolling road.

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

A longer valve duration 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 K series K12 camshaft will make a dramatic difference to the engine power band. Choosing a higher performance camshaft profile raises the power band accordingly.

NB: Fast road cams tend to bump the performance through the rpm band, you could drop a little low end power but your high end rpm power will be lifted.

Race cams, bump 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 road car you must carefully try to match your engines power to your cars usage.

You'll never have ever thought a K series K12 Race cam is a pleasure to live with when on the daily commute.

Stage 1, 2 and 3 mods for the K series K12

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 K series K12 parts:

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

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

Stage 2 K series K12 parts:

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

Stage 3 K series K12 parts:

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

The K series K12 engines respond well to upgrades and we see that there is a lot of mods and performance parts about.

A remap should help to to establish the full potential of all the tuning mods you've done to your K series K12.

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 usually depend much on the tuning mods you've applied and the condition of your engine.

Turbo modifications on the K series K12

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 K series K12.

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 your motor has forced induction upgrades are going to net you a larger power gain and you'll see that turbocharged engines use many forged and stronger components.

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

Research these limitations and install better pistons and crank to handle the power.

There are many drivers spending a lots of money on turbo upgrades on the K series K12 only to suffer the humiliation of seeing the motor explode on it's first outing after it's used in anger.

Larger upgraded turbochargers often suffer a bottom end lag, and small turbochargers spool up much more quickly but won't have the top end bhp gains.

In the last 10 years the choice of turbo chargers is always increasing and we are seeing variable vane turbo chargers, allowing the vane profile is altered according to speed to lower lag and increase top end performance.

Twin scroll turbo chargers divert the exhaust flow into two channels and direct 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 performance gains, although more challenging to get working. We have this guide to twinchargers if you want to read more.

Tips about fuel supply on the K series K12

You will need to ensure that the engine is not starved of fuel so must ramp up the fuelling when you start extending past 20% of a power hike. Don't forget to over specify your injectors flow rate.

The accepted safe increase is to add 15% when fitting an injector, this takes into account injector deterioration and allows 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 K series K12 performance exhaust upgrades

We'd only recommend you look to upgrade your exhaust system with an upgraded one is if your exhaust is creating a restriction in flow.

On most factory exhausts you'll see your 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 out of the engine but do not go 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.

Typically exhaust restrictions are traced to the catalyst and filters installed, so adding a faster flowing race 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 K series K12

Like most engines an K series K12, 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 K series K12, failure to do this will exacerbate engine wear, on a tuned K series K12 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 K series K12 why not pop over to the forums at TorqueCars where you can chat about K series K12 tuning options and read about others projects who may be planning to do similar modifications on their K series K12.

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