Modding upgrading and tuning the Volvo B6254 engine!

Everything You Need To Know About "B6254 Modifications"

How to modify and upgrade the Volvo B6254

"Comprehensive guide to tuning the Volvo B6254 engine!"

TorqueCars are always getting messages asking about how to improve the B6254 from people wanting to know what are the things tuners are recommending when it comes to B6254 mods that work. So let us look into Volvo B6254 parts and outline the best upgrades on this great engine and point out some potential pitfalls along the way.

Car Tuning Tips will look into B6254 tuning and summarise the optimum upgrades. Volvo B6254 are fantastic to work on and with carefully picked modifications like a remap, turbo kits and camshafts you will positively maximize your driving pleasure.

The best B6254 mods on an engine are as we have found the ones that give the best power gain for your hard earned cash.

We won't be swayed by popular B6254 mods, they need to be cost effective.

B6254 induction kits

Improving air intake on the B6254

You need air matched to fuel for an engine to work. If there is a lack of fuel then it will run lean, if there is not enough 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 more fuel and air into the B6254 engine is the whole point to any performance tuning task.

It is common that there's a limit in the air flow sensor AFM/MAF on the B6254 when a lot more air is being sucked into the engine.

We see 4 bar air sensors coping with quite large power gains, whereas the OEM air sensor was restricting power at a much lower level.

Intake headers carry the on the suck phase from the air cleaner and allow it to be pulled into the engine and mixed with fuel.

Structure and flow rate of the air Intake manifold can make a substantial improvement to fuel atomisation and engine efficiency on the B6254.

On popular production engines headers are begging for performance upgrades, although a few car makers provide reasonably good headers.

Larger B6254 valves, carrying out B6254 port enlargement and head flowing will also improve performance, this will afford you increasing the performance increase on other parts.

B6254 performance cam tips.

Each engine responds better to different camshaft durations than others.

The map and fuelling also will make differences on the torque gains you'll hit.

A longer valve duration 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.

Significant air intake, and exhaust improvements on the B6254 can be made from cam upgrades. Changing the cam profile alters the intake and exhaust durations on the engine and can dramatically change the bhp and power output.

NB: Fast road cams tend to push up the power across the rpm range, you might lose a little low down bhp but your top end will improve.

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

A Motorsport and race camshaft makes it harder when driving around busy urban areas.

You should ideally match your bhp range to your typical driving style so for a car used daily stick with a fast road B6254 camshaft

Stage 1, 2 and 3 mods for the B6254

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 B6254 parts:

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

Stage 2 B6254 parts:

Ported and polished head, Sports catalyst & performance exhaust, induction kit, fuel pump upgrades, 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 B6254 parts:

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

The B6254 engines are fantastic to work on and thanks to their popularity there are plenty of mods and tuning parts around.

Mapping will help unlock the full potential of all the mods you've done to your B6254.

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 differs on the mods you've applied and the condition of your engine.

Turbo modifications on the B6254

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 B6254.

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

If your car is turbocharged, modifications are going to net you a larger power gain and you'll see that turbocharged engines already contain better components.

There are common areas of failure for every engine, with some being over specified and some only able to handle stock power

Discover these restrictions and install better pistons and crank to utilize the power.

We see many car owners spending a a stack of money on turbo upgrades on the B6254 only to experience the whole thing throw a rod on it's first outing after it's first rolling road session.

Big upgraded turbo chargers commonly experience a bottom end lag, and smaller turbo chargers spool up quickly but don't have the peak rpm engines power gains.

Thankfully the selection of turbochargers is always developing and we now see variable vane turbochargers, allowing the vane angle is altered according to speed to lower lag and increase top end bhp and torque.

Twin scroll turbochargers divert the exhaust flow into two channels and flow 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 torque gains, although harder to install. We have this article covering twinchargers if you want to read more.

Tips about fuel supply on the B6254

When you improve the torque you will need to uprate to the fuel delivery.

More torque needs more fuel. Most tuners we speak with say to over specify your injectors flow rate.

As a rule of thumb add 20% to the flow rate when fitting an injector, which 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 B6254 performance exhaust upgrades

We'd only recommend you look to uprate your exhaust system with an upgraded one is if your exhaust is creating a restriction.

On most factory exhausts you should find that 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 equal out the flow of gases through the engine.

But if the exhaust is too large, ie: it's over two and a half inches diameter, you will lose much of the exhaust flow rate and end up lacking power and torque.

The usual suspects causing problems in your exhaust flow rate are in the catalysts installed, so adding a better 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 B6254

Like most engines an B6254, 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 B6254, failure to do this will exacerbate engine wear, on a tuned B6254 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 B6254 why not pop over to the forums at TorqueCars where you can chat about B6254 tuning options and read about others projects who may be planning to do similar modifications on their B6254.

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