RS4 Tuning

"RS - Racing Street, Rally Sport, Really Speedy?"

Once again Audi show the world they can make a supremely quick car that handles like it is on rails.

The RS4 is a personal favorite of mine, but one I've not managed to own (yet).

The early RS4 will benefit from a set of uprated shocks all round and on all years the turbo engines have a lot of potential for tuning up.

RS4 Tuning

The later RS4 comes as pretty much perfect from the factory but you can still add a bit more power!!

TorqueCars recommend that you get adjustable shocks and set them up to suite your driving preference and style.

Tuning tips and articles

Engine tuning Transmission tuning Care care Intake & exhaust mods Improve handling Forums

See our video which covers all the principles of tuning your Audi.

It hardly seems like there is any point tuning one of the fastest cars Audi has turned out in while. That is, until you realise just what is on offer and how much of a power gain there is waiting for you.

As with most VAG engines the RS4 engines are over engineered and can cope with bigger power gains without affecting reliability.

The RS4 is a stunning car from Audi but you can make it even better with a few simple to apply performance modifications.

The engines on offer changed through the years so here is a quick overview.  The B5 chassis RS4 built in 2000-2001 had the powerful 2.7 V6 twin cam twin turbo engine. The two blocks on offer were the ASJ and AZR. These are very interesting propositions for the tuner needing only a turbo conversion and tune/remap to boost power levels by another relatively easy 40% or so.

Then we come to the B7 chassis built around 2006-2008 with its 4.2 litre V8 Twin Cam FSi engine went back to NA (naturally aspirated) engines. Factory performance figures actually seems pessimistic with most owners squeezing the 0-62 run in around 4 seconds. This model handled much better than it's predecessor.

The B8 came along in 2012 and ran to 2015, the NASP V8 was tweaked and put out 450ps and it could only come withe the S Tronic gearbox. The 19 inch wheels were fantastic but the 20's seem to spoil the nice ride and handling you got from the 18's.

In 2018 we see the B9 revision, the V8 has been replaced with a more rev-happy 2.9 V6 thankfully twin turbo equipped and using the TFSi technology. Also the Tiptronic gearbox could now be specified. Power output was 450ps and as the block was lighter than the V8 it replaced the car feels much quicker.

Audi RS4 Tuning modifications.

These are the modified modifications are usually fitted by our members, decide how far you wish to go in your tuning project before you get going.

Getting the best tuning upgrades for your planned usage of the car is a time and money saver. Stage 3 competition upgrades just don't work well on the road hard to control in slow traffic.

Please watch our video which covers the 5 principles of tuning your car. Be sure to keep up with our latest YouTube content and subscribe.

Best Engine Mods for your car

  1. Engine Tunes - engine tuning/remapping provides the most advantage in terms of cost savings,  aftermarket ECUs, and piggyback ECUs are all alternatives.
  2. Fast road cams are one of the most significant mechanical changes, but they must be installed by someone who knows what they're doing and they are not always easy to source but you might find a local firm to regrind a stock camshaft.
  3. Intake and Exhaust - Note that on their own these mods will NOT ADD POWER in most cases, but they can help enhance power after other mods by removing the restriction.
  4. Upgrades to turbochargers and superchargers - forced induction is the most efficient approach to increase air supply, allowing you to burn more fuel and make more power. It is one of the most costly upgrades but provides the best gains.
  5. Head work - The goals of porting and flowing the head are to get air flowing into the engine while removing flow restrictions and turbulence.

Typical stage 1 mods often include: Lighter flywheel, Engine Tunes/Remapping, Panel air filter, Suspension upgrade (drop 23mm - 42 mm.), Sports exhaust, Alloy wheels.

Typical stage 2 mods often include: Power/Sport clutch, Ported and polished head, high flow fuel injector, Fast road cam, fuel pump upgrades.

Typical stage 3 mods often include: Engine balancing, Sports gearbox, Competition cam, Adding or upgrading forced induction (turbo/supercharger), Internal engine upgrades (pistons/head/valves).

Peak power is nice in motorsport but for a drivable and fun car you need a wide power band and perhaps extending the rev range.

The point of our hints is to give a brief overview of car tuning upgrades and point you in the right direction, our forum is where you can ask for more detailed advice and tips on your car tuning project, the best performance parts and all aspects of modding cars.

NA (naturally aspirated) engines

A fast road camshaft often proves to be one of the best NASP power mods you can do from a single upgrade to your engine.

Adding forced induction will see phenomenal power gains but this is usually too expensive to be cost effective. Superchargers are usually easier to add than turbos. It is harder to map a turbo as the boost increases exponentially with engine speed.

Superchargers however will give a boost which is directly proportional to engine speed so is easier to map. Decreasing the engines compression ratio will allow you to add forced induction, water injection may also help prevent detonation or follow Audi's lead and explore direct cylinder injection.

Turbo engines

On the turbo engines we say REMAP REMAP REMAP, there's another 20-30% of extra power hiding in there just waiting to be extracted.

We've also seen some tuners playing with twincharging applications and making some impressively high power gains.

When you start tuning your RS4 you will find that the standard clutch starts to complain so get an uprated clutch. The excellent turbo engines are just begging to be remapped and can cope with pretty impressive power gains without any undue issues provided you shorten your service schedule.

The exhaust & intake valve durations play a huge factor in your cars power band, but be careful here, getting this wrong can upset the idle and make the car impossible to drive in traffic. You'd need to follow a cam upgrade with other mods and finish with a reflashed ECU to fully release the power gain.

You will need to ensure that the engine is not starved of fuel so will need to pay attention to the fuelling.

Using high octane petrol is another option if you find you are suffering from pinking or premature ignition on your Audi project after fitting other modifications. Improved injectors will enable you to supply sufficient fuel to the engine.

If you are increasing your fuelling with bigger injectors you will also need to get a bigger fuel pump to supply it.

Audi RS4 Intake and Exhaust Tuning.

Now we move on to the intake and exhaust and ensure proper flow through the engine. The standard RS4 setup is pretty good on both engines. For the NASP RS4 engine TorqueCars would say to go with a washable high flow cotton panel air filter. On the turbo engines, a properly setup induction kit, with a cold air feed and preferable housed in an air box.

Sports exhausts increase the flow of air through the engine. But if the exhaust is too big, ie: it's over 2.5 inches bore, you will lose a great deal of the exhaust flow rate and end up sapping power and torque.

Miltek offer a great range of performance exhausts and it is also worth sourcing a sports catalyst to release the maximum potential from the engine.

With the NASP and to a lesser degree the turbo engine, airflow through the head can be dramatically increased with some professional porting and 'polishing'. The flow rates for each port should match and be setup to take into account any other engine mods you have had done.

Head work including a polish and port and 3 or 5 angle valve job will really help to release the potential of the engine. When you heavily modify your RS4 you will see that the standard clutch starts to slip so get an uprated clutch. The best mods we would do for your RS4 are remaps, sports camshafts and induction improvements.

NA (naturally aspirated) engines do not achieve big power gains if you tune/remap them, unless you have done extensive modifications. With turbocharged engines this is another story. A tuned/remapped turbo will give significant power gains and take full advantage of the strength of the block.

Audi RS4 Wheel modifications.

Alloy wheels will help the brakes cool down and are usually lighter than the steel ones. The downside to large alloy wheels on your RS4 is that you alter your effective final drive ratio and this will have a detrimental effect on acceleration and performance. Although some people have gone larger we would stick to a 18 inch rim size as the maximum.

The RS4 is pretty heavy, although the Quattro drive system makes it feel very nimble and responsive you should always fit good quality tyres. Some RS4 owning TorqueCars members have rated the Goodyear Eagle F1 but tyre choice is subjective and we suggest you join our car forums where you can discuss RS4 tuning options in more detail.

It would also be worth reading our unbiased Audi tuning articles to get a full grasp of the benefits and drawbacks of each modification.

Please help us improve these tips by sending us your feedback in the comments box below.

We love hearing about our website visitors projects, especially the mods done and which work best for you on your car. Which helps us keep our guides and tips up to date helping others with their modified car projects. Your feedback and comments are used to keep this page up to date, and help improve the accuracy of these articles which are kept updated and constantly revised.

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2 Responses to “RS4 Tuning”

  1. Saleh says:

    Do you provide turbo kit for RS4 B7 ?

  2. TorqueCars says:

    HI Saleh, we are only an online magazine so we don’t supply parts or kits. We wish you all the best with your project and would encourage you to join our forum where RS4 owners in your area may well be able to point you in the right direction. We’d also love to hear how you get on with your project as it develops.

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