Modding upgrading and tuning the Volvo B234 engine!

Modifying and improving: "B234 Modifications"

B234 Modifications Guide

How to modify and upgrade the Volvo B234

"Comprehensive guide to tuning the Volvo B234 engine!"

TorqueCars are regularly seeing threads asking how to improve the B234 from people wanting to know what are the premier B234 power upgrades. So let us look into Volvo B234 tuning mods and outline the best mods that work on this great engine and point out some potential pitfalls along the way.

Now we shall consider B234 tuning and provide tips on the best mods that work. Volvo B234 make a good tuning project and with the ultimate performance upgrades like a remap, turbo upgrades and camshafts you will noticeably increase your driving fun.

The best B234 tuning parts on an engine are typically the ones that give the best power gain for your hard earned cash.

We won't be swayed by popular B234 tuning parts, they need to be cost effective.

B234 induction kits

Improving air intake on the B234

You need air matched to fuel for an engine to work. If there is too little fuel then it will run lean, if there is little flow of air it runs rich resulting in lost 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 fundamental goal to any tuning project to feed air into each cylinder but this has a knock on effect with the air flow sensor.

You'll commonly see there is a limitation in the air flow sensor AFM/MAP on the B234 when considerably more air is being drawn into the engine.

We note 4 bar air sensors coping with quite large power gains, whereas the OEM air sensor sapped performance at a much lower level.

Air Intake manifolds transmit the air from the filter and allow it to be sucked into the engine cylinders with fuel for the squish phase.

Design and flow characteristics of the Plenum can make a large effect on to fuel atomisation on the B234.

Commonly we find the intake are improved through motorsport parts, although some car makers provide reasonably well designed intake.

Adding a B234 larger valve kit, doing some port work and head flowing will also raise power, and significantly will afford you a better power increase on other tuning parts.

B234 performance cam tips.

Different B234 engines respond better to less aggressive cam durations so set your engine up on a rolling road.

The ECU mapping and injectors and fuel pump also will say much on the torque gains you'll get.

Altering 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.

Altering your B234 camshaft will make a dramatic difference to the engine bhp. Choosing a higher performance camshaft profile raises the bhp accordingly.

NB: Fast road cams usually push up the bhp through the rev range, you could sacrifice a little bottom end bhp but the high end rpm power will be higher.

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

A Motorsport cam won't do well if on the daily commute.

You should ideally match your bhp range to your preferences so for a road car stick with a fast road B234 cam

Stage 1, 2 and 3 mods for the B234

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 B234 parts:

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

Stage 2 B234 parts:

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

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

Stage 3 B234 parts:

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

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

Remapping will help unlock the full potential of all the modifications you've done to your B234.

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 figures achieved may depend much on the modifications you've applied and the condition of your engine.

Turbo modifications on the B234

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 B234.

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 your car is turbocharged, upgrades are going to make more power and you'll see that turbo charged engines use better components.

However most engines have weakspots

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

It's not unheard of mechanics spending a lot of money on turbo upgrades on the B234 only to suffer the indignity of watching the car catastrophically fail on it's first outing after it's finished.

Larger capacity turbo units often suffer a bottom end lag, and little turbo units spool up really quickly but don't have the high rpm bhp gains.

In the last 10 years the range of turbochargers is always moving on and we commonly find variable vane turbochargers, where the vane angle is altered according to speed to lower lag and increase top end performance.

Twin scroll turbochargers divert the exhaust flow into two channels and push these at differently profiled vanes in the turbocharger. 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 performance gains, although more challenging to get working. We have this article covering twinchargers if you want to read more.

Tips about fuel supply on the B234

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

The rule of thumb is to add another 15% when buying an injector, helps cope with injector deterioration and affords you some 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 B234 performance exhaust upgrades

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

On most factory exhausts you'll see your flow rate is still 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 generally help improve 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 for best results.

The usual suspects causing problems in your exhaust flow rate can be located the catalyst and filters installed, so adding a better flowing high 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 B234

Like most engines an B234, 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 B234, failure to do this will exacerbate engine wear, on a tuned B234 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 B234 why not pop over to the forums at TorqueCars where you can chat about B234 tuning options and read about others projects who may be planning to do similar modifications on their B234.

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