Ford Focus RS Tuning

"Thank you for reading this Ford Focus RS tuning article."

Released in 2015 to much anticipation the RS was warmly recieved, sharing a Mustang engine but tuned to put out 350bhp instead of the Mustangs 320hp.

In addition to upraded suspension and brakes we see the Torque-Vectoring All-Wheel-Drive system  working really well, to get all that power down, and it was mated to the GKN rear drive unit.

Toward the end of the 2nd generation the RS was fitted with a Quaife mechanical limited-slip differential and RevoKnuckle front suspension which aided traction and handling and helped improve the performance.

See our video which provides a complete introduction to Ford Tuning, it contains some tips on performance and handling modifications.

A third generation is due out soon, with a battery hybrid option which we tip to offer around 400bhp,

The Focus RS is a brilliant car modification project to take up your weekends. With the right mods your Focus RS can be transformed into a fun car. Don't waste money, do your homework and follow our unbiased guides to each performance upgrade to avoid disappointment.

Tuning tips and articles

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

Focus RS Handling/Suspension upgrades

Many Focus RS owners uprate the handling of their cars with uprated suspension upgrades as a priority, this will certainly increase your enjoyment of the car.

Don't get us wrong, Ford have done a fantastic job of setting up the RS and putting all that power down. The Drift mode setting is a great option and makes you feel like you've got something very special indeed.

Good suspension tweaks that dramatically benefit handling for the Focus RS include a altering the camber by a small amount and say, 1-1.5 degrees of toe in or out on the front wheels. Toe in for stability, or Toe out to improve cornering. It would also pay to improve the brakes, by adding larger discs and or higher friction pads.,  (moving towards toe in improves straighy line stability, toe out boost cornering).

Uprated Bushes

What factors should you consider when setting up and selecting your bushes if your Focus RS is also used as a daily driver?

Bushings, which are rubber mounts, allow the Focus RS's suspension components to be affixed to the car's chassis. The rubber ones will degrade with time.

Installing new OEM rubber bushings may dramatically improve the performance of your car.

Because polyurethane bushings are stiffer, the ride may be rougher, but the bushings will last longer and maintain the car's handling over a longer time.

They may also accelerate the decay of other suspension parts due to the increased vibration and play.

A new set of poly bushings might assist in lessen the excessive play associated with rubber bushings.

Some poly bushings are hard to locate, but most will find the primary mounts readily available in their local stores You may be able to have custom polyeyurothane bushings created to suit your needs.

A common misconception is that a non-adjustable suspension system that lowers the vehicle by80mm from a franchised component shop is the best option. But suspension design and setup is quite complex.

Vendors may assert that their Focus RS suspension kits are compatible with any or all of the Focus RS model years.

The 'one size fits all' approach is obviously a flawed assumption when it comes to adequately supporting a diverse variety of cars. Engine weights and trim levels, and even alloy rims will affect the handling and require different suspension setups.

How low should you go on the Focus RS?

TorqueCars research and testing indicate that the maximum suspension drop for most road vehicles is 28 - 38 millimetres, whereas the maximum suspension drop for hot hatchbacks with lower OEM suspension is 18 millimetres.

These tolerances may be drastically diminished if the wheel size is changed. Even with 17" wheels and stock suspension, lowering the vehicle might result in lots of issues.

Stability may be improved by lowering the Focus RS, but the ultimate goal should always be to enhance handling. It is critical to use the right shocks when employing lower springs.

Good suspension tweaks that greatly benefit handling for the Focus RS include a couple of degrees negative camber and 1-1.5 degrees of toe (set out to improve cornering or in for better stability) on the front wheels.

Focus RS Brake Upgrades

For radically enhanced stopping fit better high friction brake pads and combine this with better brake discs.

As a word of warning please note that race brake pads will be noisy and will have to be hot before they start to work.

In every day driving the brakes are only used rarely so won't be all that effective so choose pads which don't need to be really hot.

RS Limited Slip Differentials

Fitting Quaife mechanical limited-slip differential on the early models seems to be quite a popular upgrade, and breakers yards should have some of these in stock from newer RS models which have had a prematurely short life due to enthusiastic driving.

We suggest that you fit sports suspension and lower the car by 22mm - 44 mm. Larger drops require arch work - especially on models already equipped with performance suspension.

Our aim in Focus RS engine tuning should be to increase peak power and Torque at the top end.

Keep it looking standard and remove the badges creating a sleeper!

Smaller engines do not provide much of a return in terms of power so start with a bigger engine. Engine swaps are a good option if you have a small engine size.

Power mods.

2.3 L EcoBoost GDI i4 engine 350 hp (261 kW) @ 6000 RPM 350 lbft (470 Nm) @ 3200 RPM (This engine is also used in the Ford Mustang)

Typically these motorsport modifications are usually carried out by our members, decide how far you wish to go in your tuning project before you get started.

Getting the right sports modifications 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 mods for your Focus RS

  1. Air Intake and Exhaust Upgrades - NB: on their own these mods will NOT ADD TORQUE for most setups, but they can help release power after other upgrades by freeing up a restriction.
  2. Braking Mods - Enhancing your stopping power needs to be high on your agenda.
  3. Fast road cams are generally the biggest mechanical mod upgrade, but ideally be fitted by someone qualified to set them up and tracking one down may be hard but you might have a local firm to regrind a stock camshaft for you.
  4. Focus RS Suspension Upgrades - Replacing worn bushings and shocks dramatically improves Focus RS handling Coilovers and Bushings are the usual go to mods
  5. Lightened Flywheels - a lower mass flywheel will significantly improve the engines free revving nature. Not always recommended for all Focus RS engines.
  6. Internal engine mods - crank, pistons, conrods & compression ratio including balancing and blueprinting
  7. Turbo upgrades - forced induction is the most dramatic method to raise the intake air supply, ensuring you are able to utilize more fuel and make better power figures. It is one of the most technically difficult modifications it offers big gains.
  8. Remaps - A Remapped Focus RS ECU provides the most power for your outlay, replacement ECUs, and Tuning boxes are all alternatives.

Focus RS Tuning Stages

Typical stage 1 mods often include: Alloy wheels, Suspension upgrade (drop 22mm - 44 mm.), Remap, Panel air filter, Sports exhaust, Lighter flywheel.

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

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

Your aim when tuning should be a wide torque range. You want to avoid sending all the power to be at the top end of the rev range unless you are creating a motor sport car.

The point of our guides is to give a starting base of modding upgrades and point you in the right direction, our forum is the place to go for detailed advice and tips on your tuning project, the best tuning modifications and all aspects of modding cars.Fast road cams offer one of the biggest power gains for your money as far as a bolt on modified parts goes on a NA (naturally aspirated) engine.

The intake & exhaust flow play a big role 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 camshaft upgrade with other mods and finish with a reflashed ECU for the best performance gains.

When pushing up the power you will need to uprate to the fuelling. More power needs more fuel.

Frequently power losses, and erratic idling after modifications are done can usually be traced to timing or fuelling issues. To get sufficient fuel you may need to uprate the injectors on your engine.

A fuel pump will only deliver a finite amount of fuel, so you may need to uprate this if your injectors are demanding more fuel.

Intake and Exhaust Tuning.

Now we move on to the intake and exhaust and ensure proper flow through the engine. Air induction kits only help to boost power if your cars air intake is restricted! Adding an induction kit to most standard engines will see NO LOW END POWER GAIN AT ALL. If you have heavily modified your engine and it's need for air INCREASES DRAMATICALLY then an induction kit is the answer and will help remove this restriction.

Derestricting the air flow into the engine is a primary goal of tuning so get a better flowing air filter if you find that the car is running lean only if you find the car is running lean. Induction kits can sound fun but due to the warm air in the engine bay they will not add noticeable power and often rob you of power.

Sports exhausts can usually air flow out of the engine but avoid an exhaust that is too big or you could very well end up with a reduced flow rate. So generally speaking, keep to 1.5 to 2.5 inches as a rule of thumb.

gas flowing the head will allow you to maximise your air/fuel charge. Leave this to a professional though with a proper flow bench and machine tools In nearly all cases of Focus RS tuning your clutch will start to slip and this should be improved - read our overview on clutches for more information. The best mods that we recommend for your Focus RS are a remap especially on a turbo, a fast road camshaft and sports exhaust, with a good air intake.

NA (naturally aspirated) engines do not achieve big power gains if you remap them, unless you have done extensive modifications. With turbocharged engines this is another story. A remapped turbo will give phenomenal power gains and take full advantage of the strength of the block. Despite the large cost involved adding forced induction to a NA (naturally aspirated) engine will give large power gains. It is usually easier to bolt on a supercharger than it is to fit a working turbo. Turbos increase power in increasing proportion to increasing engine speed and this can make mapping difficult.

Superchargers however will give a boost which is directly proportional to engine speed so is simpler. Decreasing the engines compression ratio will allow you to add forced induction, water injection may also help prevent detonation.

Alloy wheel upgrades.

Due to the fact that alloy wheels are less heavy they improve performance and they help to cool the brake disks. Pay attention to your choice of tyres (tires) for your car, a good directional tread pattern tire can really enhance your cars handling. The drawback to large alloys on your Focus RS is that you're changing your effective final drive ratio so this will have a negative effect on acceleration.

Due to this fact endeavour to keep the overall rolling diameter of the wheel the same as supplied from the factory. In all cases we do not recommend going above 19 inches but we prefer the feel you get with 18's if we're totally honest here.

If you would like to know more, or just get some friendly advice on Tuning your car please join us in our friendly forum where you can discuss Focus RS options in more detail with our Focus RS owners. It would also be worth reading our unbiased Ford tuning articles to get a full grasp of the benefits and drawbacks of each modification.

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