Ford Duratec 37 Tuning (3.7 V6 Cyclone)

"All you need to know about tuning the Ford Duratec 37 engine!"

One engine that keeps cropping up in emails and questions we get sent, is the Duratec 37, and what parts work best on it. So we've created this guide to take you through what we feel are the main modifications that you should tune and outline which modifications we feel are the best.

As a result of a joint effort between Ford and Porsche, the V6 Duratec engine was first introduced. The Duratec family is a sturdy adaptable variety of 4 5 and 6 cylinder engines with inline and V layout units within the roster. In a variety of configurations and levels of tune, the original block design proved to be flexible and sturdy.

The Radical RXC V6 engine is based on the Duratec 37 Cyclone, while Ginetta's 3.7Ti-VCT produces 310 horsepower and this goes some way to show what the Duratec 37 Ford Cyclone V6 Engine 3.7 L  DOHC V6 is capable of.

The Ford Duratec 37 really good project engines and with a few sensible tuning parts like a remap, turbo kits and camshafts you will noticeably increase your driving experience.

TorqueCars will review Duratec 37 tuning and highlight the premier modifications for your car. A growing number of performance and upgrade components are being made available for the Duratec engine blocks.

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

History of the Duratec 37 Engine

The Duratec 37 Cyclone features a larger cylinder bore diameter, resulting in an increase in displacement over the 3.5 however, the piston stroke of the Duratec 37 is the same as that of the Duratec 3.5 so it retains many of the characteristics of its smaller capacity brother.

The Radical RXC V6 engine is based on the Duratec 37 Cyclone, while Ginetta's 3.7Ti-VCT produces 310 horsepower and this goes some way to show what the Duratec 37 Ford Cyclone V6 Engine 3.7 L  DOHC V6 is capable of.

  • Duratec 37 Ford Cyclone V6 Engine 3.7 L  DOHC V6 2008–present

  • 2008 – 2009 Mazda CX-9
  • 2009 – 2013 Mazda 6
  • 2011 – 2013 Ford F150
  • 2011 – 2014 Ford Mustang
  • 2011 – 2014 Ford Edge Sport
  • 2015 – 2019 Ford Transit
  • 2015 – 2017 Ford Mustang

Tuning the Ford Duratec 37 and best Duratec 37 performance parts.

Best tuning mods

Just because particular tuning parts are popular with Duratec 37 owners it doesn't mean its worth having, we will concentrate on the best tuning parts that will give your Duratec 37 the best power gain for you spend.

Please watch our video which covers the 5 principles of tuning your Duratec 37. Be sure to keep up with our latest YouTube content and subscribe.

Best mods for your Duratec 37

  1. ECU Tunes - A remap provides the biggest gains for the money, replacment 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 are doing and they are not always easy to source but you might find a local firm to regrind a stock camshaft.
  3. Intake Upgrades and Performance Exhausts - NB: on their own these mods won't ADD POWER in most cases, but they can help enhance power after other mods by removing the restriction.
  4. Turbo upgrades - 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 it offers big gains.
  5. Internal engine mods - crank, pistons, conrods & compression ratio including balancing and blueprinting

Duratec 37 Tuning Stages

Typical stage 1 mods often include: Fast road camshaft, Sports exhaust manifold, Panel air filters, Remaps/piggy back ECU, Intake manifolds, Drilled & smoothed airbox.

Typical stage 2 mods often include: fuel pump upgrades, Ported and polished head, Sports catalyst & performance exhaust, induction kit, high flow fuel injectors, Fast road cam.

Typical stage 3 mods often include: Engine balancing & blueprinting, Crank and Piston upgrades to alter compression, Twin charging conversions, Internal engine upgrades (head flowing porting/bigger valves), Adding or Upgrading forced induction (turbo/supercharger), Competition cam.

Camshaft Upgrades

Sporty camshaft profiles raise the upper RPM range power so are more suited to petrol engines, than diesel ones. You will usually get a peak power hikes through performance camshafts on most engines.

But with the Duratec units, emphasis on lift, to get as much work out of those valves as possible.

Significant gains on the Duratec 37 can be made from cam upgrades. Altering the cam profile alters the intake and exhaust durations on the engine and can dramatically change the engines power and power output.

Fast road camshafts tend to push up the performance through the rev band, you may sacrifice a little low down torque but the higher rpm power will be higher.

Race camshafts, push up the higher rpm power band but as a result the car will not idle smoothly and low end power nearly always suffers.

A Motorsport camshaft will just annoy you whilst in heavy traffic.

You should ideally optimize your engines power to your typical driving style so for a daily driver stick with a mild fast road Duratec 37 camshaft

Different Duratec 37 engines respond differently primarily due to the airflow when cams are fitted depending on the cam being less aggressive cam durations so view each engine and camshaft as unique due to manufacturing tolerances and quality variations so check your engine on a rolling road.

The map and fuel delivery and fuel pump also will say much on the torque gains you'll hit.

A longer valve duration can alter the torque band, and on most engines there are some advantages to extending the intake or exhaust durations and valve lift.

Carefully think through your options and then find your parts and set yourself a power target to avoid disappointment.

ECU Mapping Improvements

Mapping helps to establish the full potential of all the tuning mods you've installed on your Duratec 37.

(Sometimes remapping the ECU is not an option, so an aftermarket ECU is the route to take, and many of these will outperform factory ECU's but check it has knock protection and that you get it setup properly.) It will usually give around 30% more power on turbocharged vehicles and you can expect to see around 15% on NA (naturally aspirated) engines, but the end result usually rely on the tuning mods you've fitted and the condition of your engine.

Air Flow improvements

It is the goal to any car tuning task to force more air and fuel into each cylinder

Intake carry the air from the filter and allow it to be drawn into the engine cylinders.

The shape and rate of flow of the Intake can make a big improvement to fuel atomisation and engine efficiency on the Duratec 37.

It's not uncommon that manifolds are begging for aftermarket tuning parts, although a few makers provide decently flowing headers.

Larger valve conversions on the Duratec 37, doing a bit of Duratec 37 port enlargement and head flowing will also improve power, & more importantly will afford you an improved power increase on other modifications.

Duratec 37 Turbo upgrades

NA (naturally aspirated) engines need quite a lot of work when you add a turbo, so we have a separate guide to help you take into account the pros and cons of going this route on your Duratec 37 if you are feeling adventurous and have deep pockets.

Boosting the induction system with a turbocharger upgrade is a great way to increase horsepower and torque.

Every engine has a certain amount of power that it can manage, and some are overspecified while others can only handle stock power. To manage the power, investigate these limitations and install stronger cranks and pistons.

Turbo charger modifications on the Duratec 37 are sometimes accompanied with an engine block explosion when they're utilised in a rage.

Big turbochargers frequently have low-end latency, while small turbochargers spool up rapidly but don't have the top-end horsepower benefits.

We now have variable vane turbo chargers, which enable the vane angle to be adjusted according to speed in order to reduce latency and boost top-end torque.

It is possible to use twin scroll turbo chargers to route exhaust gases into two separate channels, which run through the turbo charger at various angles. They also enhance the engine's ability to scavenge.

The Duratec 37 Cylone's air flow sensor AFM/MAF often shows a limitation when the engine is drawing in more air than normal.

4 bar sensors are able to handle relatively substantial power boosts, but the OEM air sensor was limited to a considerably lower level.

Adding a supercharger or additional turbo will make large bhp and torque gains, although more difficult to get working. We have this in depth look at twinchargers if you want to read more.

Fuelling Upgrades

Don't overlook the need to uprate the fuel delivery when you are increasing the performance - it makes the car more thirsty. Boosting the fuel pressure can improve the acceleration responsiveness.It makes sense to over specify your injector capacity.

As a rule of thumb add 20% when fitting an injector, helps cope with injector deterioration and provides some spare capacity should the engine require more fuel.

We think this one is common sense, but you'll need to match your fuel injector to the type of fuel your car uses as well.

Performance Exhausts

If your exhaust is causing a limitation, you should consider upgrading it.

Even with small power improvements, the flow rate on most factory exhausts should be enough. However, when power levels rise, you'll need a better-flowing exhaust.

Even while sports exhausts may improve airflow through the engine, you should avoid using one that is too wide since it can restrict the flow rate. In general, you'll get the best results by staying within a range of 1.5 to 2.5 inches.

Modifications such as a sports catalyst effectively eliminate this constraint, mostly owing to its bigger size and surface area, and will effectively improve performance to the levels you would anticipate without having a catalyst fitted.

As a result of the increased interior surface area and improved design, this automobile remains road legal. Since removing a catalyst from a road-registered automobile is prohibited in many places (and you can't even replace a functional catalyst in others), any alternative decat or catalyst removal should be reserved for off-road use exclusively.

Weak spots, Issues & problem areas on the Duratec 37

The Duratec 37 engines are not bad as far as reliability goes as long as they are well maintained.

Due to the single coil supplying all cylinders, Duratecs seem to be more prone to coil failure than other engines.

Plug gaps are fairly crucial on most of these engines, thus having them adjusted right is a requirement with many owners gapping them somewhat wider than the OEM standards.

Valve clearance should be checked on engines without hydraulic lifters every year, otherwise you'll be losing power or misfires from inadequate valve lift.

Water pump failure is quite a common issue, with Ford switching to an external unit on the revised Duratec engines. Having a water pump inside the engine made replacement difficult and failure just happens without warning or symptom.

Carbon build up in the head, particularly around the valves which will sap power or create flat spots, this is a larger issue on direct injection engines but should be looked out for on all engines. We have tips on removing carbon To minimize this risk only use quality fuel and don't short journeys.

Service time oil changes are vital on the Duratec 37, and more so when the car is modified and will help maintain the long life of the engine.

If you want to know more, or just get more pointers on Tuning your Duratec 37 engine please join us in our friendly forum where you can discuss Duratec 37 tuning options in more detail with our Duratec 37 owners. It would also be worth reading our unbiased Ford tuning articles to get insights into each modification and how effective they will be.

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

We love to know what our visitors have got up to and which mods work best for them on each model of car. We use your comments and feedback to improve the accuracy of these Duratec 37 tuning guides which get regular updates and revisions.

Please Check out my YouTube channel, we're regularly adding new content...

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