Modding and performance tuning parts for the VAG D24 engine!

Explore D24 Modifications"

How to modify and upgrade the VAG D24

"Comprehensive guide to performance tuning the VAG D24 engine!"

TorqueCars often are getting messages requesting information on how to improve the D24 from people wanting to know what are the best tips on D24 power upgrades. So let us look into VAG D24 upgrades and outline the best mods that work on this great engine and point out some potential pitfalls along the way.

The VAG D24 are popular engines and with carefully picked tuning upgrades like a remap, turbo kits and camshafts you will enhance your driving enjoyment.

In this article we outline options for your D24 tuning and provide tips on the optimum upgrades.

The best D24 modifications on an engine are in our opinion the ones that give the biggest return for your money.

We won't be swayed by popular D24 modifications, they need to be cost effective.

D24 induction kits

Improving air intake on the D24

You need fuel and air for an engine to work. If there is not enough fuel then it will run lean, if there is too little 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 Feeding air into the D24 engine is the whole point to any car tuning job.

It is common that there is a restriction in the air flow sensor MAP/MAF/AFM on the D24 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 was restricting bhp and torque at a much lower level.

Intake carry the on the suck phase from the intake filter and allow it to be pulled into the engine and mixed with fuel.

Shape and flow characteristics of the Intake headers can make a large improvement to fuel atomisation and engine efficiency on the D24.

It's not uncommon that intake are begging for a performance upgrade, although a few manufacturers provide decently flowing intake.

Fitting big valve kits, carrying out port matching and head flowing will also boost bhp, and more importantly will give you raising the bhp increase on other tuning parts.

D24 performance cam tips.

Some D24 engines respond better to more aggressive cam durations so set your engine up on a rolling road.

The ecu map and fuelling also will say much on the power gains you'll make.

Longer 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 D24 can be made from cam upgrades. Changing the cam profile alters the intake and exhaust durations on the engine and can dramatically change the torque and power output.

NB: Fast road camshafts normally push up the bhp and torque through the rev band, you may sacrifice a little low down power but your top end will be lifted.

Competition camshafts, push up the top end band but as a result the car will not idle smoothly and low end power nearly always suffers.

For a daily driver you need to match your engines power to your cars usage.

I'd be gobsmaked if you find a D24 Motorsport camshaft is a pleasure to live with when driving around busy urban areas.

Stage 1, 2 and 3 mods for the D24

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 D24 parts:

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

Stage 2 D24 parts:

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

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

Stage 3 D24 parts:

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

Review your options and then source your parts and set yourself a power target to save yourself from expensive mistakes.

Remaps will help release the full potential of all the upgrades you've done to your D24.

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 will rely on the upgrades you've done and the condition of your engine.

Turbo modifications on the D24

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 D24.

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 the engine has a turbo already fitted parts are more reliable and turbo charged engines are made using better components.

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

We recommend you find these restrictions and install higher quality crank and pistons to utilize the power.

We see many guys spending a fortune on turbo upgrades on the D24 only to experience the engine go up in smoke just after it's used in anger.

Bigger upgraded turbo chargers often suffer no power at low rpm, and smaller turbo chargers spool up more quickly but do not have the peak rpm engines power gains.

In the last 10 years the selection of turbo chargers is always developing and we commonly find variable vane turbo chargers, where the vane angle is altered according to speed to lower lag and increase top end power.

Twin scroll turbo chargers divert the exhaust flow into 2 channels and feed these at differently profiled vanes in the turbocharger. 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 performance gains, although more difficult to setup. We have this feature on twinchargers if you want to read more.

Tips about fuel supply on the D24

Don't forget to improve the fuel delivery when you are increasing the bhp and torque - it makes the car more thirsty. Most tuners we speak with say to be generous with your injectors flow rate.

As a rule of thumb add another 15% when fitting an injector, this takes into account injector deterioration and gives you some 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 D24 performance exhaust upgrades

You may need to increase your exhaust system with an upgraded one is if your exhaust is actually creating a restriction in flow.

On most factory exhausts you'll find 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.

Note that with the biggest exhaust you can find you'll reduce the exhaust flow rate - the best 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.

Typically exhaust restrictions are in the catalyst installed, so adding a faster flowing 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 D24

Like most engines an D24, 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 D24, failure to do this will exacerbate engine wear, on a tuned D24 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 D24 why not pop over to the forums at TorqueCars where you can chat about D24 tuning options and read about others projects who may be planning to do similar modifications on their D24.

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