Modding upgrading and tuning the Vauxhall N14YF engine!

Modifying and improving: "N14YF Modifications"

N14YF Modifications Guide

How to modify and upgrade the Vauxhall N14YF

"Comprehensive guide to performance tuning the Vauxhall N14YF engine!"

Our friends at TorqueCars often are getting emails about how to improve the N14YF from people wanting to know what are the greatest N14YF power upgrades. So let us look into Vauxhall N14YF mods and outline the best upgrades on this great engine and point out some frequent tuning mistakes along the way.

We shall look into N14YF tuning and point out the premier mods that work. Vauxhall N14YF are awesome to work on and with carefully chosen uprated parts like remaps, turbo kits and camshafts you will improve your driving experience.

Just because particular modifications are popular with N14YF owners it doesn't mean it is good, we shall focus on the best modifications that will give your N14YF the best power gain for you money.

Without us subscribing to the mentality 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'.

N14YF induction kits

Improving air intake on the N14YF

You need air and fuel for an engine to work. If there is too little fuel then it will run lean, if there is not enough air it runs rich resulting in lost power . We'll pick up on fuelling later in this article but for now we shall look at air supply.

So it's important to any engine tuning task to force more fuel and air into the N14YF engine but this has a knock on effect with the air flow sensor.

It is not unusual that there's a restriction in the air flow sensor AFM/MAP on the N14YF when loads more air is being fed into the engine.

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

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

The shape and rate of flow of the Air Intake manifolds can make a large difference to to fuel mixing and power on the N14YF.

It's not uncommon that intake are begging for performance upgrades, although some manufacturers provide reasonably well designed intake.

Big valve conversions on the N14YF, getting 3 or 5 angle valve jobs and porting and head flowing will also raise bhp, & more importantly will give you a greater bhp increase on other upgrades.

N14YF performance cam tips.

Some N14YF engines respond better to less aggressive cam durations check your engine on a rolling road.

The ecu map and fuelling also have a large bearing on the power gains you'll get.

Altering valve durations 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.

Significant air intake, and exhaust improvements on the N14YF can be made from cam upgrades. Changing the cam profile alters the intake and exhaust durations on the engine and can dramatically change the power band and power output.

NB: Fast road cams tend to push up the performance through the rpm range, you could sacrifice a little bottom end bhp but high end rpm power will be lifted.

Race cams, 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 Race camshaft won't do well if on the daily commute.

You should ideally optimize your engines power to your preferences so for a daily driver stick with a fast road N14YF camshaft

Stage 1, 2 and 3 mods for the N14YF

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 N14YF parts:

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

Stage 2 N14YF parts:

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

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

Stage 3 N14YF parts:

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

The N14YF engines respond well to mods and we see that there are increasing numbers of modifications and performance parts around.

Mapping will help release the full potential of all the parts you've done to your N14YF.

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 outcome may depend much on the parts you've done and the condition of your engine.

Turbo modifications on the N14YF

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 N14YF.

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 the engine is turbocharged, mods are more reliable and most turbocharged engines are built using uprated components.

There are tuning limits for every engine, with some being over specified and some only able to handle stock power

See where you'll find these restrictions and upgrade to better quality components to cope with the power.

We've seen mechanics spending a fortune on turbo upgrades on the N14YF only to suffer the humiliation of seeing the engine explode soon after it's used on the roads.

Larger capacity turbos will usually experience a bottom end lag, and little turbos spool up more quickly but won't have the top end bhp gains.

Thankfully the range of turbo chargers is always improving and we now see variable vane turbo chargers, allowing the vane profile is altered according to speed to lower lag and increase top end power.

Twin scroll turbo chargers divert the exhaust flow into two channels and push these at differently profiled vanes in the turbo. They also help the scavenging effect of the engine.

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

Tips about fuel supply on the N14YF

You will need to ensure that the engine is not starved of fuel so will have to increase the fuelling when you start going beyond 20% of a bhp hike. At this point we flag up the need to over specify your injector capacity.

As a rule of thumb add another 15% when specifying an injector, this takes into account injector deterioration and gives 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 N14YF performance exhaust upgrades

You should look to upgrade your exhaust system with an upgraded one is if the current exhaust is actually causing a restriction.

On most factory exhausts you should find that 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.

Do not go with the widest exhaust you can buy you'll slow the exhaust rate - the best exhausts 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.

Usual exhaust restrictions come around the emissions filters installed, so adding a freer flowing high performance 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 N14YF

Like most engines an N14YF, 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 N14YF, failure to do this will exacerbate engine wear, on a tuned N14YF 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 N14YF why not pop over to the forums at TorqueCars where you can chat about N14YF tuning options and read about others projects who may be planning to do similar modifications on their N14YF.

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