Modding uprating the BMW S63 engine!

All you need to know about "S63 Modifications"

S63 Modifications Guide

How to modify and upgrade the BMW S63

"Comprehensive guide to tuning and performance parts on the BMW S63 engine!"

Forums like the one at TorqueCars are frequently getting posts asking how to improve the S63 from people inquiring about getting more power from the S63 and wanting to know what are the things tuners are recommending when it comes to S63 power upgrades. So let us look into BMW S63 parts and outline the best mods that work on this great engine and point out some common pitfalls along the way.

The BMW S63 great bases for a tuning project and with the optimum sports parts like ECU maps, turbo improvements and camshafts you will certainly improve your driving enjoyment.

Our aim here is to examine S63 tuning and show the best modifications for your car.

When talking about the top parts for your S63 engine, we are going to concentrate on the tuning parts that give the best value for money.

S63 induction kits

Improving air intake on the S63

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 a lack of 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 aim to any engine upgrade task to force fuel and air into each cylinder but this has a knock on effect with the air flow sensor.

It is common that there is a limitation in the air flow sensor (AFM/MAF/MAP) on the S63 when considerably more air is being drawn into the engine.

When tuning you may well find you need to get an air sensor or flow meter capable of upto 4 bars to cope with quite large power gains, whereas the OEM air sensor limited torque at a much lower level.

Intake manifolds take the air from the air cleaner and allow it to be sucked into the engine and mixed with fuel.

Shape and flow characteristics of the air Intake manifold can make a big effect on to fuel engine efficiency on the S63.

We often see air intake manifolds are crying out for aftermarket parts, although some OEM provide reasonably good air intake manifolds.

Fitting big valve kits, getting 3 or 5 angle valve jobs and porting and head flowing will also lift torque, and significantly will afford you raising the torque increase on other modifications.

S63 performance cam tips.

Each engine responds better to more aggressive cam durations than others.

The map and injectors and fuel pump also will make differences on the power gains you'll achieve.

A longer valve duration 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.

Altering your S63 cam will make a dramatic difference to the engine engines power. Choosing a higher performance cam profile raises the engines power accordingly.

NB: Fast road cams tend to push up the bhp through the rev band, you could sacrifice a little low down power but the higher rpm power will be higher.

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.

For a typical daily driver you must carefully try to optimize your bhp range to your usage of the car.

I'd be surprised if you have found a S63 Race cam is a pleasure to live with when on the daily commute.

Stage 1, 2 and 3 mods for the S63

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 S63 parts:

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

Stage 2 S63 parts:

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

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

Stage 3 S63 parts:

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

The S63 engine blocks respond well to mods and thankfully there is a growing number of modifications and performance parts out there.

ECU mapping allows a tuner to unlock the full potential of all the tuning parts you've done to your S63.

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 usually vary depending on the tuning parts you've carried out and the condition of your engine.

Turbo modifications on the S63

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 S63.

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 motor is turbo charged tuning mods are going to make more power and you will discover turbocharged engines are made using harder and stronger components.

There are reliable limits for every engine, with some being incredibly solid and some only able to handle stock power

It is important to find these limits and install better pistons and crank to cope with the power.

We see many people spending a lot of money on turbo upgrades on the S63 only to have the engine block throw a rod when it's used in anger.

Big turbochargers tend to experience a bottom end lag, and little turbochargers spool up quickly but do not have the top end engines power gains.

Thanks to new tech the choice of turbo units is always moving on and we commonly find variable vane turbo units, allowing the vane profile is altered according to speed to lower lag and increase top end bhp and torque.

Twin scroll turbo units divert the exhaust gases 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 bhp gains, although more challenging to get working. We have this feature on twinchargers if you want to read more.

Tips about fuel supply on the S63

You will need to ensure that the engine is not starved of fuel so should ramp up the fuelling when you start extending past 20% of a bhp and torque hike. Care modifiers usually say to be generous with your flow rate on the injectors.

The accepted safe increase is to add another 15% when buying an injector, this takes into account injector deterioration and provides 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 S63 performance exhaust upgrades

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

On most factory exhausts you'll find the exhaust 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.

Don't go with the biggest exhaust you can buy you'll slow the exhaust 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 can be traced to the filters installed, so adding a better flowing performance alternative will help avoid this restriction.

Cat bypassing (NB:catalysts reduce harmful engine emissions) is illegal in most countries and regions.

Faults issues and things to look out for on the S63

Like most engines an S63, 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 S63, failure to do this will exacerbate engine wear, on a tuned S63 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 S63 why not pop over to the forums at TorqueCars where you can chat about S63 tuning options and read about others projects who may be planning to do similar modifications on their S63.

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