Modding and performance tuning parts for the Volvo B204 engine!

All you need to know about "B204 Modifications"

How to modify and upgrade the Volvo B204

"Comprehensive guide to performance parts and tuning the Volvo B204 engine!"

Our friends at TorqueCars often are getting messages about how to improve the B204 from people wanting to know what are the greatest B204 mods that work. So let us look into Volvo B204 mods and outline the best mods that work on this great engine and point out some common pitfalls along the way.

Now we shall examine the options for your B204 tuning and summarise the best modifications. Volvo B204 make awesome project engines and with a few sensible performance mods like remaps, turbo upgrades and camshafts you will maximise your driving fun.

Just because particular mods are popular with B204 owners it doesn't mean you should fit it, instead we'll concentrate on the greatest mods that will give your B204 the best value for money to power increase.

Without us subscribing to the common myth 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'.

B204 induction kits

Improving air intake on the B204

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

So the primary aim to any engine tuning task to feed more fuel and air into the B204 engine but this has a knock on effect with the air flow sensor.

It is not unusual that there's a limitation in the air flow sensor (AFM/MAF/MAP) on the B204 when a lot more air is being drawn 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 air during the suck phase from the air filter and allow it to be pulled into the engine cylinders with fuel for the squish phase.

The size of bore and shape and flow rate of the Intake can make a big effect on to fuel engine efficiency on the B204.

Commonly we find the air intake manifolds are improved through performance upgrades, although a few manufacturers provide well optimised air intake manifolds.

Adding a B204 larger valve kit, doing some port work and head flowing will also lift performance, & importantly will permit an improved performance increase on other tuning parts.

B204 performance cam tips.

Each engine responds better to mild camshaft durations so view each engine as unique.

The engine timing and fuel pump and injectors also will say much on the bhp gains you'll hit.

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.

Significant air intake, and exhaust improvements on the B204 can be made from camshaft upgrades. Changing the camshaft profile alters the intake and exhaust durations on the engine and can dramatically change the torque and power output.

NB: Fast road cams tend to bump the bhp and torque through the rpm range, you might lose a little bottom end torque but the high end rpm power will improve.

Motorsport and race cams, bump the high end rpm power band but as a result the car will not idle smoothly and low end power nearly always suffers.

For a daily driver you must carefully try to match your power band to your usage of the car.

You'll never find a B204 Race camshaft is a pleasure to live with when driving around busy urban areas.

Stage 1, 2 and 3 mods for the B204

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 B204 parts:

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

Stage 2 B204 parts:

fuel pump upgrades, Fast road cam, Ported and polished head, 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 B204 parts:

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

The B204 power plant respond well to upgrades and thanks to their popularity there is a growing number of parts and performance parts around.

A remap helps unlock the full potential of all the modifications you've done to your B204.

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 end result may vary depending on the modifications you've done and the condition of your engine.

Turbo modifications on the B204

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 B204.

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

When your car has forced induction upgrades are more reliable and you'll see that turbo charged engines use uprated components.

There are reliable limits for every engine, with some being very over engineered and some only able to handle stock power

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

There are many people spending a loads of money on turbo upgrades on the B204 only to suffer the humiliation of seeing the car explode on it's first outing after it's completed.

Larger capacity turbos will usually suffer low end lag, and small turbos spool up more quickly but won't have the peak end torque gains.

In recent times the market of turbos is always evolving and we now see variable vane turbos, permitting the vane angle is altered according to speed to lower lag and increase top end performance.

Twin scroll turbos divert the exhaust flow into a couple of channels and flow 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 bhp gains, although more difficult to get working. We have this feature on twinchargers if you want to read more.

Tips about fuel supply on the B204

Don't miss you'll need to uprate the fuel system when you are increasing the torque - it makes the car more thirsty. We strongly recommend you to over specify your injector capacity.

As a rule of thumb add 15% to the flow rate when specifying an injector, this accounts for injector deterioration and gives a little 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 B204 performance exhaust upgrades

The only time you should 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.

Do not go with the widest exhaust you can get this will reduce the exhaust flow 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.

The usual suspects causing problems in your exhaust flow rate come around the catalyst and filters installed, so adding a better flowing sports 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 B204

Like most engines an B204, 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 B204, failure to do this will exacerbate engine wear, on a tuned B204 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 B204 why not pop over to the forums at TorqueCars where you can chat about B204 tuning options and read about others projects who may be planning to do similar modifications on their B204.

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