Modding uprating the Vauxhall C14SE engine!

Tuning guide "C14SE Modifications"

How to modify and upgrade the Vauxhall C14SE

"Comprehensive guide to tuning and performance parts on the Vauxhall C14SE engine!"

Our friends at TorqueCars are frequently getting posts requesting information on how to improve the C14SE from people inquiring about getting more power from the C14SE and wanting to know what are the greatest C14SE power upgrades. So let us look into Vauxhall C14SE parts and outline the best mods that work on this great engine and point out some common pitfalls along the way.

The Vauxhall C14SE are awesome to work on and with the optimum motorsport mods like a remap, turbo kits and camshafts you will maximize your driving pleasure.

We shall review C14SE tuning and summarise the best modifications for your car.

Just because particular parts are popular with C14SE owners it doesn't mean its worth having, we shall concentrate on the ultimate parts that will give your C14SE the biggest power gain return for your cash.

Without us subscribing to the popular 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'.

C14SE induction kits

Improving air intake on the C14SE

You need air matched to fuel for an engine to work. If there is little supply of fuel then it will run lean, if there is little flow of air it runs rich losing power . We'll pick up on fuelling later in this article but for now we shall look at air supply.

So Feeding air into your C14SE is vital to any engine performance tuning task.

You'll commonly see there is a restriction in the air flow sensor AFM/MAP on the C14SE when a lot more air is being pulled into the engine.

When tuning you may well find you need to get an air sensor or flow meter capable of upto 4 bars to cope with quite large power gains, whereas the OEM air sensor limited torque at a much lower level.

Headers carry the on the suck phase from the intake filter and allow it to be pulled into the engine cylinders.

Design and flow characteristics of the Headers can make a substantial improvement to fuel atomisation on the C14SE.

We often see intake manifold are needing motorsport parts, although a few makers provide reasonably well designed intake manifold.

Adding a C14SE larger valve kit, getting port matching and head flowing will also boost bhp and torque, & more importantly will make space for an improved bhp and torque increase on other upgrades.

C14SE performance cam tips.

Some C14SE engines respond better to less aggressive camshaft durations check your engine on a rolling road.

The ecu map and injectors and fuel pump also have a large bearing on the bhp gains you'll achieve.

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 C14SE cam will make a dramatic difference to the engine torque. Choosing a higher performance cam profile raises the torque accordingly.

NB: Fast road camshafts normally increase the bhp over the rpm range, you may sacrifice a little low end power but the top end will improve.

Competition 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 typical daily driver you must carefully try to optimize your bhp range to your usage of the car.

I'd be gobsmaked if you have found a C14SE Motorsport camshaft is a pleasure to live with when driving around busy urban areas.

Stage 1, 2 and 3 mods for the C14SE

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 C14SE parts:

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

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

Stage 2 C14SE parts:

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

Stage 3 C14SE parts:

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

The C14SE power plant respond well to mods and we see that there is an increase of parts and tuning parts around.

A remap allows a tuner to fully realize the full potential of all the mods you've done to your C14SE.

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 will differs on the mods you've carried out and the condition of your engine.

Turbo modifications on the C14SE

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 C14SE.

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.

If your motor is turbo charged tuning parts are simpler to install and most turbo charged engines already contain many forged and stronger components.

However every engines will need better parts at higher power limits

We recommend you find these limits and fit higher quality crank and pistons to cope with the power.

There are many tuners spending a lots of money on turbo charger upgrades on the C14SE only to suffer the indignity of watching the engine block catastrophically fail just after it's been enthusiastically driven.

Large turbos often experience low end lag, and low capacity turbos spool up quickly but do not have the peak rpm power band gains.

Over the last 20 years the selection of turbochargers is always improving and we now see variable vane turbochargers, where the vane profile is altered according to speed to lower lag and increase top end bhp.

Twin scroll turbochargers divert the exhaust flow into two channels and push these at differently profiled vanes in the turbo charger. 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 power gains, although more challenging to get working. We have this in depth look at twinchargers if you want to read more.

Tips about fuel supply on the C14SE

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

As a rule of thumb add 15% capacity when fitting an injector, helps cope with injector deterioration and gives 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 C14SE performance exhaust upgrades

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

On most factory exhausts you'll see the 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 increase the flow of air through the engine.

But if your exhaust pipe is too big, ie: over two and a half inches diameter, you will lose much of your flow rate and end up sapping power and torque.

Usual exhaust restrictions come around the filters installed, so adding a better flowing race alternative will help avoid this restriction.

Decats (NB:catalysts reduce harmful engine emissions) is illegal in most countries and regions.

Faults issues and things to look out for on the C14SE

Like most engines an C14SE, 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 C14SE, failure to do this will exacerbate engine wear, on a tuned C14SE 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 C14SE why not pop over to the forums at TorqueCars where you can chat about C14SE tuning options and read about others projects who may be planning to do similar modifications on their C14SE.

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