Modding tuning and best performance upgrades on the Fiat Firefly N4 engine!

Car tuning tips:Firefly N4 Modifications"

Firefly N4 Modifications Guide

How to modify and upgrade the Fiat Firefly N4

"Comprehensive guide to tuning the Fiat Firefly N4 engine!"

Popular tuning sites like TorqueCars are frequently getting emails about how to improve the Firefly N4 from people inquiring about getting more power from the Firefly N4 and wanting to know what are the premier Firefly N4 modifications. So let us look into Fiat Firefly N4 upgrades and outline the best modifications on this great engine and point out some frequent tuning mistakes along the way.

Car Tuning Tips will look into Firefly N4 tuning and show the best upgrades. Fiat Firefly N4 make a good tuning project and with the right motorsport enhancements like remaps, turbo upgrades and camshafts you will really maximise your driving experience.

When talking about the best parts for your Firefly N4 engine, we are going to concentrate on the ones that give the biggest return for your cash.

Firefly N4 induction kits

Improving air intake on the Firefly N4

You need air matched to fuel for an engine to work. If there is a lack of 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 the fundamental goal to any car tuning project to pull more air and fuel into the Firefly N4 engine but this has a knock on effect with the air flow sensor.

It is common that there is a limitation in the air flow sensor MAF/MAP on the Firefly N4 when considerably 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 limited bhp and torque at a much lower level.

Engine intake manifolds flow the on the suck phase from the filter and allow it to be drawn into the engine cylinders.

The shape and rate of flow of the Headers can make a substantial effect on to fuel atomisation and engine efficiency on the Firefly N4.

Commonly we find the intake manifold are in dire need of performance upgrades, although a few OEM provide decently flowing intake manifold.

Adding a Firefly N4 larger valve kit, getting port matching and head flowing will also raise bhp and torque, and significantly will give you raising the bhp and torque increase on other tuning parts.

Firefly N4 performance cam tips.

Some Firefly N4 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 ECU mapping and fuel pump and injectors also have a large bearing on the power gains you'll hit.

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 engines power gains are on offer for camshaft upgrades.

NB: Fast road camshafts normally push up the bhp across the rpm band, you could sacrifice a little bottom end power but the high end rpm power will be better.

Competition camshafts, push up 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 camshaft will just annoy you whilst driving in heavy traffic.

You should ideally optimize your power band to your driving style so for a car used daily stick with a mild fast road Firefly N4 camshaft

Stage 1, 2 and 3 mods for the Firefly N4

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 Firefly N4 parts:

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

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

Stage 2 Firefly N4 parts:

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

Stage 3 Firefly N4 parts:

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

The Firefly N4 engine blocks respond well to mods and we're happy to report there is a lot of mods and tuning parts around.

Remapping helps to establish the full potential of all the modifications you've done to your Firefly N4.

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 vary depending on the modifications you've done and the condition of your engine.

Turbo modifications on the Firefly N4

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 Firefly N4.

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.

If your motor is turbocharged, mods are going to net you a larger power gain and you will discover turbo engines are made with many forged and stronger components.

There are practical limits for every engine, with some being extremely strong and some just sufficiently able to handle stock power

Discover these limits and fit better pistons and crank to cope with the power.

It's not unheard of mechanics spending a lot of money on turbo charger upgrades on the Firefly N4 only to suffer the humiliation of seeing the car go up in smoke when it's completed.

Bigger turbochargers commonly experience low end lag, and smaller turbochargers spool up quickly but do not have the peak end bhp gains.

Thanks to progress the range of turbos is always increasing and we are seeing variable vane turbos, allowing the vane profile is altered according to speed to lower lag and increase top end bhp.

Twin scroll turbos divert the exhaust gases into a couple of channels and direct these at differently profiled vanes in the turbo charger. 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 torque gains, although more complex to install. We have this in depth look at twinchargers if you want to read more.

Tips about fuel supply on the Firefly N4

When you increase the power you will need to pay attention to to the fuel system.

More power needs more fuel. Care modifiers usually say to be generous with your injectors flow rate.

The accepted safe increase is to add 20% when fitting an injector, this accounts for injector deterioration and allows a little 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 Firefly N4 performance exhaust upgrades

Only look to replace your exhaust system with an upgraded one is if your current exhaust is actually creating a flow problem.

On most factory exhausts you'll see the exhaust 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.

Sports exhausts can usually air flow through the engine but avoid an exhaust that is too wide or you may end up will reduce the flow rate. Stick to one and a half to two and half inches for best results.

Usual exhaust restrictions can be traced to the catalyst installed, so adding a higher 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 Firefly N4

Like most engines an Firefly N4, 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 Firefly N4, failure to do this will exacerbate engine wear, on a tuned Firefly N4 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 Firefly N4 why not pop over to the forums at TorqueCars where you can chat about Firefly N4 tuning options and read about others projects who may be planning to do similar modifications on their Firefly N4.

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