Modding uprating the Volvo B4204 engine!

Tuning guide "B4204 Modifications"

B4204 Modifications Guide

How to modify and upgrade the Volvo B4204

"Comprehensive guide to tuning the Volvo B4204 engine!"

Sites like TorqueCars often are getting messages asking how to improve the B4204 from people wanting to know what are the greatest B4204 modifications. So let us look into Volvo B4204 parts and outline the best mods that work on this great engine and point out some problems along the way.

We shall examine the options for your B4204 tuning and report on the best modifications for your car. Volvo B4204 are good project engines and with the ultimate parts like remaps, turbo kits and camshafts you will greatly maximize your driving fun.

The best B4204 parts on an engine are obviously the ones that give the biggest return for your money.

We won't be swayed by popular B4204 parts, they need to be cost effective.

B4204 induction kits

Improving air intake on the B4204

You need fuel and air for an engine to work. If there is little supply of fuel then it will run lean, if there is a lack of 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 the aim to any engine performance tuning task to force more air into your B4204 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 MAP/MAF/AFM on the B4204 when considerably 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 sapped torque at a much lower level.

Engines intake headers take the on the suck phase from the air cleaner and allow it to be drawn into the engine cylinders.

Design and flow characteristics of the Intake headers can make a substantial effect on to fuel atomisation and engine efficiency on the B4204.

Many mass produced engine intake are begging for aftermarket parts, although some car makers provide fairly well optimized intake.

Larger B4204 valves, doing a bit of 3 or 5 angle valve jobs and porting and head flowing will also raise bhp and torque, and significantly will afford you a greater bhp and torque increase on other upgrades.

B4204 performance cam tips.

Different B4204 engines respond better to different cam durations so set your engine up on a rolling road.

The engine timing and fuelling also will say much on the bhp gains you'll achieve.

Altering valve durations 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 B4204 can be made from cam upgrades. Changing the cam profile alters the intake and exhaust durations on the engine and can dramatically change the engines power and power output.

NB: Fast road cams tend to push up the torque over the rev range, you may lose a little low end torque but your higher rpm power will improve.

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

A Motorsport cam makes it harder when driving in heavy traffic.

You should ideally match your engines power to your cars usage so for a car driven daily stick with a fast road B4204 cam

Stage 1, 2 and 3 mods for the B4204

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 B4204 parts:

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

Stage 2 B4204 parts:

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

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

Stage 3 B4204 parts:

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, Twin charging conversions, Competition cam.

The B4204 power plant are great to work on and we see that there is a lot of mods and performance parts around.

A remap helps fully realize the full potential of all the parts you've done to your B4204.

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 may differs on the parts you've carried out and the condition of your engine.

Turbo modifications on the B4204

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 B4204.

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 a car has a turbo already fitted parts are going to make more power and you will discover turbocharged engines will have harder and stronger components.

However every engines will have power limits

We recommend you find these restrictions and install higher quality components to cope with the power.

It's not unheard of tuners spending a lot of money on turbo charger upgrades on the B4204 only to watch the motor literally blow up soon after it's been enthusiastically driven.

Bigger capacity turbo chargers will usually suffer low end lag, and small turbo chargers spool up more quickly but do not have the top end power band gains.

Thankfully the world of turbos is always evolving and we now see variable vane turbos, allowing the vane angle is altered according to speed to lower lag and increase top end torque.

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

Tips about fuel supply on the B4204

When you raise the bhp you will need to look at to the fuelling.

More bhp needs more fuel. Experienced mechanics will tell you to be generous with your flow rate on the injectors.

The accepted safe increase is to add 15% when fitting an injector, this takes into account injector deterioration and affords a little 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 B4204 performance exhaust upgrades

You should look to increase your exhaust system with an upgraded one is if your exhaust is creating a restriction in flow.

On most factory exhausts you'll find your flow rate is ok 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 help 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 the exhaust flow rate and end up lacking power and torque.

Usual exhaust restrictions can be located the emissions filters installed, so adding a higher flowing sports 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 B4204

Like most engines an B4204, 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 B4204, failure to do this will exacerbate engine wear, on a tuned B4204 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 B4204 why not pop over to the forums at TorqueCars where you can chat about B4204 tuning options and read about others projects who may be planning to do similar modifications on their B4204.

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