Modding uprating the BMW M10 engine!

Car tuning tips:M10 Modifications"

M10 Modifications Guide

How to modify and upgrade the BMW M10

"Comprehensive guide to performance tuning the BMW M10 engine!"

Forums like the one at TorqueCars are always getting messages asking about how to improve the M10 from people inquiring about getting more power from the M10 and wanting to know what are the ultimate M10 upgrades. So let us look into BMW M10 parts and outline the best modifications on this great engine and point out some problems along the way.

The BMW M10 offer good returns when tuned and with carefully chosen sports parts like a remap, turbo upgrades and camshafts you will definitely improve your driving pleasure.

Let us detail the best approach to M10 tuning and provide tips on the ultimate modifications.

Just because particular tuning mods are are common on M10 it doesn't mean you should fit it, so we'll focus on the greatest tuning mods that will give your M10 the best value for money to power increase.

Without us subscribing to the popular 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'.

M10 induction kits

Improving air intake on the M10

You need fuel and air for an engine to work. If there is too little fuel then it will run lean, if there is insufficient air it runs rich resulting in lost power which risks damage to the M10. We'll pick up on fuelling later in this article but for now we shall look at air supply.

So Shoving more fuel and air into your M10 is the primary aim to any tuning job.

You'll commonly see there's a limit in the air flow sensor (AFM/MAF/MAP) on the M10 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 was restricting torque at a much lower level.

Intake carry the air from the filter and allow it to be drawn into the engine and mixed with fuel.

Structure and flow rate of the Headers can make a substantial effect on to fuel mixing and power on the M10.

On popular production engines intake are crying out for aftermarket parts, although a few OEM provide well optimised intake.

Fitting big valve kits, doing a bit of port work and head flowing will also lift bhp, and significantly will afford you an improved bhp increase on other tuning mods.

M10 performance cam tips.

Each engine responds better to more or less aggressive cam durations check your engine on a rolling road.

The ecu map and fuelling also have an effect 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.

The camshaft profile plays a big part in the engines power output so camshaft upgrades make quite a large difference. The intake and exhaust durations will alter depending on the chosen camshaft profile, so large bhp gains are on offer for camshaft upgrades.

NB: Fast road camshafts tend to push up the torque over the rev band, you could drop a little low end power but your high end rpm power will improve.

Race camshafts, 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 and race cam is not great in heavy traffic.

You should ideally optimize your torque band to your driving style so for a typical daily driver stick with a shorter duration M10 cam

Stage 1, 2 and 3 mods for the M10

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 M10 parts:

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

Stage 2 M10 parts:

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

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

Stage 3 M10 parts:

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

Carefully think through your options and then source your parts and set yourself a power target to avoid wasting your time and money.

Remaps should help to release the full potential of all the modifications you've done to your M10.

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 power output often depend much on the modifications you've fitted and the condition of your engine.

Turbo modifications on the M10

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 M10.

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

If an engine is fitted with a turbo parts are going to make more power and you will discover turbocharged engines are made with harder and stronger components.

However every engines will have power limits

See where you'll find these limits and install forged components to utilize the power.

There are many drivers spending a loads on turbo charger upgrades on the M10 only to see the engine block catastrophically fail just after it's been enthusiastically driven.

Big capacity turbochargers will usually experience low end lag, and small turbochargers spool up much more quickly but won't have the top end torque gains.

In the last 10 years the selection of turbochargers is always improving and we are seeing variable vane turbochargers, permitting the vane profile is altered according to speed to lower lag and increase top end power.

Twin scroll turbochargers divert the exhaust flow into a couple of channels and push these at differently designed vanes in the turbo charger. They also improve 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 install. We have this feature on twinchargers if you want to read more.

Tips about fuel supply on the M10

Don't omit to raise the fuel delivery when you are increasing the performance - it makes the car more thirsty. It makes sense to over specify your flow rate on the injectors.

The accepted safe increase is to add another 15% when fitting an injector, helps cope with injector deterioration and allows 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 M10 performance exhaust upgrades

We'd only recommend you look to increase your exhaust system with an upgraded one is if your current exhaust is creating a flow problem.

On most factory exhausts you should find that the exhaust flow rate is fine 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.

Please dont run with the largest exhaust you can source this will 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.

Usual exhaust restrictions can be located the emissions filters installed, so adding a faster 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 M10

Like most engines an M10, 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 M10, failure to do this will exacerbate engine wear, on a tuned M10 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 M10 why not pop over to the forums at TorqueCars where you can chat about M10 tuning options and read about others projects who may be planning to do similar modifications on their M10.

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