Modding upgrading and tuning the Renault K9K engine!

Tuning guide "K9K Modifications"

K9K Modifications Guide

How to modify and upgrade the Renault K9K

"Comprehensive guide to tuning the Renault K9K engine!"

TorqueCars often are getting messages about how to improve the K9K from people wanting to know what are the best tips on K9K power upgrades. So let us look into Renault K9K parts and outline the best modifications on this great engine and point out some potential pitfalls along the way.

The Renault K9K provide a fun base for your project and with the right sports parts like remapping, turbo upgrades and camshafts you will noticeably increase your driving pleasure.

We shall review and look at K9K tuning and report on the ultimate modifications for your car.

Just because particular tuning mods are popular with K9K owners it doesn't mean its worth having, instead we will concentrate on the greatest tuning mods that will give your K9K the best value for money to power increase.

Without us subscribing to the popular myth 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'.

K9K induction kits

Improving air intake on the K9K

You need air matched to fuel for an engine to work. If there is too little fuel then it will run lean, if there is a lack of air it runs rich sapping 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 Pulling fuel and air into your K9K is the primary aim to any performance tuning job.

You'll commonly see there's a restriction in the air flow sensor MAF/MAP on the K9K when considerably more air is being fed into the engine.

You'll see that 4 bar air sensors coping with quite large power gains, whereas the OEM air sensor was restricting torque at a much lower level.

Air Intake manifolds transmit the air from the air filter and allow it to be fed into the engine cylinders.

Shape and rate of flow of the Headers can make a large effect on to fuel delivery on the K9K.

I usually find headers are needing performance upgrades, although a few OEM provide well optimised headers.

Fitting big valve kits, getting 3 or 5 angle valve jobs and porting and head flowing will also improve power, and importantly will permit a better power increase on other tuning mods.

K9K performance cam tips.

Different K9K 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 engine timing and fuel pump and injectors also have an effect on the torque gains you'll achieve.

Longer valve 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.

Significant air intake, and exhaust improvements on the K9K can be made from camshaft upgrades. Changing the camshaft profile alters the intake and exhaust durations on the engine and can dramatically change the power band and power output.

NB: Fast road camshafts tend to increase the power throughout the rev band, you might lose a little bottom end power but high end rpm power will be lifted.

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

A Motorsport and race cam won't do well if driving in heavy traffic.

You should ideally optimize your torque band to your driving style so for a car driven daily stick with a fast road K9K cam

Stage 1, 2 and 3 mods for the K9K

Stage 1 K9K parts:

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

Stage 2 K9K parts:

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

Stage 3 K9K parts:

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

The K9K engines make great tuning projects and we're finding that there is an increase of mods and tuning parts around.

Mapping helps fully realize the full potential of all the parts you've done to your K9K.

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

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 will rely on the parts you've done and the condition of your engine.

Turbo modifications on the K9K

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 K9K.

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.

When your motor is fitted with a turbocharger parts are simpler to install and most turbo engines use harder and stronger components.

There are reliable limits for every engine, with some being very over engineered and some only able to handle stock power

We recommend you find these restrictions and fit better pistons and crank to handle the power.

There are many mechanics spending a lot of money on turbo upgrades on the K9K only to suffer the indignity of watching the engine block throw a rod soon after it's used on the roads.

Bigger upgraded turbos often experience no power at low rpm, and smaller turbos spool up much more quickly but won't have the top end torque gains.

Thanks to new tech the world of turbos is always developing and we commonly find variable vane turbos, allowing the vane angle is altered according to speed to lower lag and increase top end power.

Twin scroll turbos divert the exhaust flow into 2 channels and push these at differently angled vanes in the turbocharger. 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 performance gains, although more difficult to install. We have this in depth look at twinchargers if you want to read more.

Tips about fuel supply on the K9K

Don't forget to increase the fuel delivery when you are increasing the power - it makes the car more thirsty. It is important to be generous with your injectors flow rate.

As a rule of thumb add 15% capacity when specifying an injector, helps cope with injector deterioration and allows you some 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 K9K performance exhaust upgrades

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

On most factory exhausts you'll find your flow rate is 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.

Do not go with the widest exhaust you can buy you'll slow up the exhaust flow rate - the best for power gains are usually between one and a half to two and half inches. Your exhaust design, the bend angles and construction are what have more effect on flow rates than your pipe width to a certain extent. So the exhaust design is a big factor.

Typically exhaust restrictions can be located the catalyst and filters installed, so adding a freer 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 K9K

Like most engines an K9K, 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 K9K, failure to do this will exacerbate engine wear, on a tuned K9K 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 K9K why not pop over to the forums at TorqueCars where you can chat about K9K tuning options and read about others projects who may be planning to do similar modifications on their K9K.

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