Modding tuning and best performance upgrades on the Vauxhall Z24XE FlexPower engine!

Everything You Need To Know About "Z24XE FlexPower Modifications"

How to modify and upgrade the Vauxhall Z24XE FlexPower

"Comprehensive guide to performance tuning the Vauxhall Z24XE FlexPower engine!"

Our friends at TorqueCars are always getting messages about how to improve the Z24XE FlexPower from people inquiring about getting more power from the Z24XE FlexPower and wanting to know what are the best Z24XE FlexPower mods that work. So let us look into Vauxhall Z24XE FlexPower mods and outline the best modifications on this great engine and point out some potential pitfalls along the way.

Let us look into Z24XE FlexPower tuning and point out the premier modifications. Vauxhall Z24XE FlexPower make a good tuning project and with the best modified enhancements like a remap, turbo improvements and camshafts you will positively increase your driving experience.

Just because particular modifications are popular with Z24XE FlexPower owners it doesn't mean it is good, we will concentrate on the best modifications that will give your Z24XE FlexPower the biggest power gain return for your cash.

Without us subscribing to the misaprehension 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'.

Z24XE FlexPower induction kits

Improving air intake on the Z24XE FlexPower

You need fuel and air 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 which risks damage to the Z24XE FlexPower. We'll pick up on fuelling later in this article but for now we shall look at air supply.

So the aim to any tuning task to force air and fuel into your Z24XE FlexPower but this has a knock on effect with the air flow sensor.

It is not unusual that there's a limit in the air flow sensor MAF/MAP on the Z24XE FlexPower when loads more air is being pulled into the engine.

You'll see that 4 bar air sensors coping with quite large power gains, whereas the OEM air sensor limited bhp and torque at a much lower level.

Headers carry the during the engines suck phase from the filter and allow it to be drawn into the engine and mixed with fuel.

The bore size, shape and flow characteristics of the air Intake manifold can make a big change to fuel mixing and power on the Z24XE FlexPower.

On popular production engines air intake manifolds are needing aftermarket tuning parts, although a few manufacturers provide reasonably good air intake manifolds.

Big valve conversions on the Z24XE FlexPower, doing a bit of port matching and head flowing will also boost power, & more importantly will permit raising the power increase on other tuning parts.

Z24XE FlexPower performance cam tips.

Each engine responds better to more or less aggressive cam durations so set your engine up on a rolling road.

The map and fuelling also have an effect on the bhp gains you'll make.

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.

The cam profile plays a big part in the engines power output so cam upgrades make quite a large difference. The intake and exhaust durations will alter depending on the chosen cam profile, so large bhp gains are on offer for cam upgrades.

NB: Fast road cams normally raise the performance throughout the rpm range, you could sacrifice a little bottom end power but high end rpm power will be higher.

Competition cams, raise 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 cam is not great in heavy traffic.

You should ideally optimize your engines power to your preferences so for a typical daily driver stick with a mild fast road Z24XE FlexPower cam

Stage 1, 2 and 3 mods for the Z24XE FlexPower

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 Z24XE FlexPower parts:

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

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

Stage 2 Z24XE FlexPower parts:

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

Stage 3 Z24XE FlexPower parts:

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

Carefully think through your options and then buy your tuning parts and set yourself a power target to save yourself from expensive mistakes.

Remapping will help to establish the full potential of all the modifications you've done to your Z24XE FlexPower.

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 your results often vary depending on the modifications you've fitted and the condition of your engine.

Turbo modifications on the Z24XE FlexPower

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 Z24XE FlexPower.

The more air you can get into an engine, the more fuel it can burn and uprating the induction with a turbocharger upgrade makes massive power gains.

If your motor is fitted with a turbo tuning parts are going to make more power and most turbo engines will have strengthened components.

However you'll find engines will need better parts at higher power limits

See where you'll find these restrictions and fit better pistons and crank to survive the power.

It's not unheard of drivers spending a fortune on turbocharger upgrades on the Z24XE FlexPower only to watch the engine go up in smoke just after it's finished.

Big turbochargers will usually experience low end lag, and low capacity turbochargers spool up more quickly but won't have the top end power band gains.

We are pleased that the world of turbo units is always developing and we are seeing variable vane turbo units, allowing the vane profile is altered according to speed to lower lag and increase top end power.

Twin scroll turbo units divert the exhaust flow into 2 channels and push these at differently designed vanes in the turbocharger. They also boost 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 harder to configure. We have this feature on twinchargers if you want to read more.

Tips about fuel supply on the Z24XE FlexPower

You will need to ensure that the engine is not starved of fuel so will have to pay attention to the fuelling when you start going beyond 20% of a power hike. It makes sense to over specify your flow rate on the injectors.

The rule of thumb is to add 20% when fitting an injector, this allows for injector deterioration and gives a bit of 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 Z24XE FlexPower performance exhaust upgrades

We'd only recommend you look to upgrade your exhaust system with an upgraded one is if the current exhaust is actually causing a flow problem.

On most factory exhausts you'll see your flow rate is still 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 can usually air flow through the engine but do not go too big 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 are in the filters installed, so adding a higher flowing performance alternative will help avoid this restriction.

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

Faults issues and things to look out for on the Z24XE FlexPower

Like most engines an Z24XE FlexPower, 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 Z24XE FlexPower, failure to do this will exacerbate engine wear, on a tuned Z24XE FlexPower 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 Z24XE FlexPower why not pop over to the forums at TorqueCars where you can chat about Z24XE FlexPower tuning options and read about others projects who may be planning to do similar modifications on their Z24XE FlexPower.

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