Modding tuning and best performance upgrades on the Vauxhall X20XER engine!

All you need to know about "X20XER Modifications"

How to modify and upgrade the Vauxhall X20XER

"Comprehensive guide to performance tuning the Vauxhall X20XER engine!"

Sites like TorqueCars are frequently getting emails requesting information on how to improve the X20XER from people wanting to know what are the best X20XER power upgrades. So let us look into Vauxhall X20XER parts and outline the best upgrades on this great engine and point out some frequent tuning mistakes along the way.

Therefore we provide a guide to X20XER tuning and provide tips on the greatest modifications for your car. Vauxhall X20XER are popular tuning projects and with the best modified upgrades like ECU maps, turbo improvements and camshafts you will dramatically improve your driving fun.

When talking about the ultimate parts for your X20XER engine, we are going to concentrate on the parts that give the best value for money.

X20XER induction kits

Improving air intake on the X20XER

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

So Feeding more fuel and air into your X20XER is the main goal to any engine performance tuning job.

You'll commonly see there is a limit in the air flow sensor (AFM/MAF/MAP) on the X20XER when considerably more air is being drawn 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 sapped performance at a much lower level.

Headers carry the during the engines 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 flow characteristics of the Headers can make a large effect on to fuel atomisation on the X20XER.

It's not uncommon that intake headers are needing aftermarket parts, although some manufacturers provide well optimised intake headers.

Big valve conversions on the X20XER, carrying out port matching and head flowing will also raise performance, & importantly will give you a better performance increase on other upgrades.

X20XER performance cam tips.

Different X20XER engines respond better to mild cam durations than others.

The ecu map and fuelling also have a large bearing 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 X20XER can be made from camshaft upgrades. Changing the camshaft profile alters the intake and exhaust durations on the engine and can dramatically change the engines power and power output.

NB: Fast road camshafts commonly raise the bhp and torque over the rpm band, you may sacrifice a little low end power but higher rpm power will improve.

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

On a typical daily driver you need to optimize your engines power to your usage of the car.

I'd be surprised if you have ever thought a X20XER Race cam is a pleasure to live with when on the daily commute.

Stage 1, 2 and 3 mods for the X20XER

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 X20XER parts:

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

Stage 2 X20XER parts:

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

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

Stage 3 X20XER parts:

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

The X20XER engines respond well to upgrades and we're pleased to see that there is a growing number of mods and performance parts around.

A remap should help to release the full potential of all the tuning mods you've done to your X20XER.

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 power output usually differs on the tuning mods you've fitted and the condition of your engine.

Turbo modifications on the X20XER

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 X20XER.

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 your motor is fitted with a turbo parts are going to net you a larger power gain and you will discover turbocharged engines are built with stronger components.

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

Research these restrictions and install stronger pistons, crank and engine components to cope with the power.

We've seen guys spending a lot of money on turbo upgrades on the X20XER only to see the engine literally blow up on it's first outing after it's been completed.

Bigger capacity turbos will usually experience a bottom end lag, and small turbos spool up much more quickly but don't have the peak rpm bhp gains.

In the last 10 years the world of turbos is always evolving and we commonly find variable vane turbos, allowing the vane angle is altered according to speed to lower lag and increase top end bhp.

Twin scroll turbos divert the exhaust flow into a couple of channels and feed these at differently angled 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 article covering twinchargers if you want to read more.

Tips about fuel supply on the X20XER

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

The accepted safe increase is to add 15% capacity when buying an injector, this accounts for injector deterioration and provides a bit of 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 X20XER performance exhaust upgrades

Only look to improve your exhaust system with an upgraded one is if your exhaust is actually causing a flow problem.

On most factory exhausts you'll find your flow rate is good 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 will certainly help air flow from the engine but avoid an exhaust that is too large or you may end up will reduce the flow rate. Stick to one and a half to two and half inches as a rule of thumb.

Usual exhaust restrictions can be traced to the emissions filters installed, so adding a faster 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 X20XER

Like most engines an X20XER, 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 X20XER, failure to do this will exacerbate engine wear, on a tuned X20XER 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 X20XER why not pop over to the forums at TorqueCars where you can chat about X20XER tuning options and read about others projects who may be planning to do similar modifications on their X20XER.

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