Renault K4M Tuning

"All you need to know about performance parts and tuning the Renault K4M engine!"

The Renault K4M are good project engines and with the best performance parts like remaps, turbo upgrades and camshafts you will improve your driving opportunities.

Our aim here is to consider K4M tuning and summarise the best mods that work.

History, Power & Specs of the 16 Valve K4M Engine

K4M 490 E4

77 kW 105 PS 103 hp 5750 rpm

Lada Largus

K4M 69x

66 to 77 kW 90 to 105 PS 89 to 103 hp
@ 5750 rpm

Renault Kangoo II
Dacia Logan

K4M 606 4x4

77 kW 105 PS 103 hp 5750 rpm

Dacia Duster

K4M 616 LPG E5 K4M 642 LPG E5b K4M 646 4x4 K4M 696 Hi-flex

77 kW 105 PS 103 hp 5750 rpm

Dacia Duster
Dacia Logan
Dacia Sandero

K4M 70x

71 to 81 kW 97 to 110 PS 95 to 109 hp
@ 5750 rpm

Renault Mégane
Renault Scénic
Renault Clio II
Renault Kangoo
Renault Kangoo II
Renault Laguna I

K4M 710

81 kW 110 PS 109 hp 5750 rpm

Renault Laguna II

K4M 716

86 kW 117 PS 115 hp 5750 rpm

Renault Laguna II

K4M 72x

81 kW 110 PS 109 hp 5750 rpm

Renault Laguna

K4M 782

90 kW 122 PS 121 hp 5500 rpm

Renault Scenic II

K4M 788

79 kW 107 PS 106 hp 5750 rpm

Renault Mégane II

K4M 812/813/858

86 kW 117 PS 115 hp 6000 rpm

Renault Mégane II III

K4M 856 flexfuel

77 kW 105 PS 103 hp 5750 rpm

Renault Mégane Eco 2 flexfuel II

K4M 824

81 kW 110 PS 109 hp 6000 rpm

Renault Laguna III

K4M 838

82 kW 111 PS 110 hp 6000 rpm

Renault Fluence

K4M 848

74 kW 101 PS 99 hp 5500 rpm

Renault Mégane III

K4M RS ou 854

99 kW 135 PS 133 hp 6750 rpm

Renault Twingo RS
Renault Wind

K4M DHT hybrid engine E-TECH

114 hp 84 kW at 5,500 rpm

Renault Clio V PHEV
Renault Captur II PHEV

K4M DHT hybrid engine E-TECH

160 hp 118 kW at 5,500 rpm

Renault Megane IV PHEV
Renault Captur II PHEV

 

Tuning the Renault K4M and best K4M performance parts.

Best K4M parts

Just because particular modifications are are common on K4M it doesn't mean it is good, we shall focus our attention and tuning advice on the specific modifications and upgrades that will give your K4M the biggest power gain return for your cash.

Significant gains on the K4M can be made from cam upgrades. Altering the cam profile alters the intake and exhaust durations on the engine and can dramatically change the power band and power output.

Fast road camshafts usually increase the power through the rev band, you may sacrifice a little bottom end bhp but your top end will improve.

Motorsport camshafts, increase the top end 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 bhp range to your usage of the car.

I'd be completely gobsmacked if you have found a K4M Competition camshaft is a pleasure to live with when in heavy traffic because low end power will be very lumpy. Competition cams are designed for maximum power at the top end of the RPM range, a place that most daily commutes will not permit!

Each engine responds better to less aggressive cam durations so view each engine as unique.

The engine timing and injectors and fuel pump also have an effect on the bhp gains you'll get.

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.

Please watch our video which covers the 5 principles of tuning your car. Be sure to keep up with our latest YouTube content and subscribe.

Best mods for your K4M

1. Remaps - A tune/remap provides the biggest gains in terms of cost, aftermarket ECU upgrades, and inline Tuning boxes are all alternatives.
2. Fast road cams are generally the biggest mechanical mod upgrade, but they must be installed by someone who knows what they are doing and they are not always easy to source but you might find a local firm to regrind a stock camshaft.
3. Intake Mods and Performance Exhausts - NB: on their own these mods will NOT ADD POWER in most cases, but they can help enhance power after other mods by removing the restriction.
4. Forced induction upgrades - A New Turbo is the most efficient approach to increase air supply, allowing you to burn more fuel and make more power. It is one of the most costly upgrades it offers big gains.
5. Flowing and porting the engine head - for larger gains, you will get better flow and make a more efficient engine if you do this to support your other mods.

K4M Tuning Stages

Typical stage 1 mods often include:
drilled & smoothed airbox, Intake manifolds, Remaps/piggy back ECU, Sports exhaust header/manifold, Fast road camshaft, Panel air filters.

Typical stage 2 mods often include:
fuel pump upgrades, induction kit, Fast road cam, Ported and polished head, Sports catalyst & performance exhaust, high flow fuel injectors.

Typical stage 3 mods often include:
Competition cam, Adding or Upgrading forced induction (turbo/supercharger), Engine balancing & blueprinting, Internal engine upgrades (head flowing porting/bigger valves), Twin charging conversions, Crank and Piston upgrades to alter compression.

Mapping allows a tuner to fully realize the full potential of all the upgrades you've done to your K4M.

(In some cases, as the factory ECU is locked flashing is not an option, so an aftermarket ECU is the route to take, and many of these will outperform factory ECU's but make sure it has knock protection and that you get it setup properly.)

It will usually give you around 30% more power on turbocharged vehicles and you can expect to see around 15% on NA (naturally aspirated) engines, but power output often depend much on the upgrades you've carried out and the condition of your engine.

Pulling fuel and air into the K4M engine is vital to any car tuning job.

Intake manifold carry the air during the suck phase from the air filter and allow it to be sucked into the engine cylinders with fuel for the squish phase.

The shape and rate of flow of the Intake can make a substantial improvement to fuel atomisation on the K4M.

On popular production engines intake manifolds are begging for aftermarket parts, although a few manufacturers provide well optimised intake manifolds.

Fitting big valve kits, doing a bit of K4M port enlargement and head flowing will also lift bhp, and more importantly will give you raising the bhp increase on other parts.

K4M Turbo upgrades

NA (naturally aspirated) 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 K4M

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 an engine has forced induction tuning parts are going to net you a larger power gain and you'll see that turbo charged engines use uprated components.

However engines have limits.See where you'll find these limits and install forged components to cope with the power.

We've seen people spending a a stack of money on turbocharger upgrades on the K4M only to suffer the humiliation of seeing the car explode on it's first outing after it's used in anger.

Big upgraded turbos tend to experience a bottom end lag, and smaller turbos spool up quickly but don't have the high rpm power band gains.

Thanks to new tech the world of turbochargers is always moving on and we commonly find variable vane turbochargers, where the vane angle is altered according to speed to lower lag and increase top end power.

Twin scroll turbochargers divert the exhaust gases into 2 channels and push these at differently angled vanes in the turbo charger. They also boost the scavenging effect of the engine.

It is common that there's a restriction in the air flow sensor (AFM/MAF/MAP) on the K4M when a lot more air is being drawn into the engine.

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

Adding a supercharger or additional turbo will make large power gains, although harder to configure. We have this in depth look at twinchargers if you want to read more.

Fuelling

You will need to ensure that the engine is not starved of fuel so must increase the fuelling when you start exceeding 20% of a power increase.We would recommend you to over specify your injectors flow rate.

As a rule of thumb add 20% when specifying an injector, helps cope with injector deterioration and gives 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.

K4M Performance Exhausts

You only need to upgrade your exhaust if your exhaust is creating a restriction in flow.

On most factory exhausts you'll find the flow rate is still fine 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 generally help improve air flow out of the engine but do not go too big or you could very well end up with a reduced flow rate. So generally speaking, keep to 1.5 to 2.5 inches as a rule of thumb.

Usual exhaust restrictions can be traced to the emissions filters installed, so adding a better flowing high performance aftermarket one will improve air flow, and rather than doing an illegal decat, will keep the car road legal.

Weak spots, Issues & problem areas on the K4M

The K4M engines are generally reliable and solid units, as long as you follow the manufacturers service schedules, and use a good quality oil to ensure longevity. Few problems should happen as long as they are regularly serviced and maintained.

Carbon build up in the head, particularly around the valves which will sap power or create flat spots, this is a larger issue on direct injection engines but should be looked out for on all engines. We have tips on removing carbon build up.

Some of our members have had issues with flat spots or glitches after applying mods and upgrades or tuning, this is not usually related to this engines design, so instead see our article on diagnosing flat spots and problems after tuning which should help you get the bottom of this issue.

Regular oil changes are vital on the K4M, especially when tuned and will help extend the life and reliability of the engine.

If you would like to know more, or just get some friendly advice on Tuning your K4M engine please join us in our car forums where you can discuss K4M tuning options in more detail with our K4M owners. It would also be worth reading our unbiased Renault tuning articles to get insights into each modification and how effective they will be for your car.

Please help us improve these tips by sending us your feedback in the comments box below.

We love to hear what our visitors have got up to and which upgrades work best for you on your car. Which helps us keep our guides and tips up to date helping others with their modified car projects. Your feedback and comments are used to keep this page up to date, and help improve the accuracy of these K4M tuning guides which get regular updates and revisions.

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 Renault. 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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