Tuning the Ford Duratec 3.7

"Comprehensive guide to tuning and performance parts on the Ford Duratec 37 engine!"

We often are seeing threads requesting info on the greatest Duratec 37 upgrades. So let us look into Ford Duratec 37 parts and outline the best modifications on this great engine and point out some problems along the way.

The Duratec 3.7 is also internally known as the Ford Cyclone V6 Engine and was designed by Ford and Porsche in collaboration.

The Ford Duratec 37 are popular engines and with carefully chosen uprated mods like remaps, turbo upgrades and camshafts you will greatly maximize your driving opportunities.

Let us provide a guide to Duratec 37 tuning and report on the optimum upgrades.

The best Duratec 37 mods on an engine are in our opinion the ones that give the best power gain for you spend.

We won't be swayed by popular Duratec 37 mods, they need to be cost effective.

Altering your Duratec 37 cam will make a dramatic difference to the engine torque. Choosing a higher performance cam profile raises the torque accordingly.

NB: Fast road camshafts usually increase the bhp through the rev band, you may lose a little low down power but high end rpm power will be higher.

Motorsport and race camshafts, increase the high end rpm power band but as a result the car will not idle smoothly and low end power nearly always suffers.

On a daily driver you need to optimize your power band to your typical driving style.

I'd be surprised if you find a Duratec 37 Motorsport and race camshaft is a pleasure to live with when on the daily commute.

Each engine responds better to extreme camshaft durations so view each engine as unique.

The engine timing and fuel pump and injectors also will say much on the torque gains you'll make.

A longer valve duration can alter the torque 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.

Duratec 37 Best Tuning Mods & Upgrades

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Tuning Stages

Stage 1 Duratec 37 modifications: Fast road camshaft, Drilled & smoothed airbox, Intake headers, Remaps/piggy back ECU, Panel air filters, Sports exhaust manifold.

Stage 2 Duratec 37 modifications: Ported and polished head, induction kit, Sports catalyst & performance exhaust, high flow fuel injectors, fuel pump upgrades, Fast road cam.

Stage 3 Duratec 37 modifications: Competition cam, Internal engine upgrades (head flowing porting/bigger valves), Engine balancing & blueprinting, Twin charging conversions, Adding or Upgrading forced induction (turbo/supercharger), Crank and Piston upgrades to alter compression.

Mapping should help to release the full potential of all the modifications you've done to your Duratec 37.

It will usually give around 30% more power on turbocharged vehicles and you can expect to see around 15% on NASP engines, but the end result may depend much on the modifications you've fitted and the condition of your engine.

Feeding air and fuel into the Duratec 37 engine is the aim to any engine upgrade project.

Air Intake manifolds take the air during the suck phase from the intake filter and allow it to be drawn into the engine cylinders with fuel for the squish phase.

Design and rate of flow of the Headers can make a substantial effect on to fuel atomisation on the Duratec 37.

We often see intake are in dire need of motorsport parts, although some makers provide fairly well optimized intake.

Fitting big valve kits, doing some port matching and head flowing will also increase bhp and torque, and importantly will give you a greater bhp and torque increase on other mods.

Turbo upgrades for the Duratec 3.7

NASP 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

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

If an engine has a turbocharger upgrades are going to net you a larger power gain and turbocharged engines will have harder and stronger components.

There are weak spots for every engine, with some being over specified and some only able to handle stock power

Discover these limits and fit better pistons and crank to utilize the power.

We see many mechanics spending a a stack of money on turbo upgrades on the Duratec 37 only to have the car go up in smoke when it's first rolling road session.

Bigger capacity turbos will usually suffer a bottom end lag, and small turbos spool up much more quickly but don't have the peak end torque gains.

Thanks to new tech the world of turbos is always evolving and we now see variable vane turbos, permitting the vane profile is altered according to speed to lower lag and increase top end power.

Twin scroll turbos divert the exhaust gases into 2 channels and push these at differently angled vanes in the turbo. They also help the scavenging effect of the engine.

You'll commonly see there's a limit in the air flow sensor (AFM/MAF/MAP) on the Duratec 37 when a lot more air is being pulled into the engine.

We see 4 bar air sensors coping with quite large power gains, whereas the OEM air sensor sapped performance at a much lower level.

Adding a supercharger or additional turbo will make large performance gains, although harder to setup. We have this in depth look at twinchargers if you want to read more.

Uprating Duratec 3.7 fuel injectors

Don't omit to pay attention to the fuelling when you are increasing the bhp - it makes the car more thirsty. Don't forget to be generous with your injector capacity.

The accepted safe increase is to add 20% when fitting an injector, this allows for injector deterioration and affords a bit of spare capacity should the engine need 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.

Best Duratec 3.7 performance exhausts

Only look to improve your exhaust if the existing exhaust is actually creating a restriction in flow.

On most factory exhausts you'll find the flow rate is still fine even on modest power gains, but when you start pushing up the power levels you will need to get a better flowing exhaust.

Sports exhausts balance the flow of gases through the engine.

But if the exhaust is too big, ie: over 2.5 inches bore, you will lose a lot of the flow rate and end up lacking power and torque.

Common exhaust restrictions typically happen through the catalyst and or DPF filters which manufacturers fit, especially as they start to get worn and carbon builds up, so adding a better flowing sports alternative will help avoid this restriction.

Problems and issues to look out for on the Duratec 37

The Duratec 37 engines, if regularly serviced and maintained, are generally very reliable and have few issues.

Regular oil changes are vital on the Duratec 37, particularly when the engine has been modified and is putting down more power than the manufacturer intended.

For more information on Tuning your Duratec 37 engine please join us in our friendly forum where you can discuss tuning options in more detail with our Duratec 37 owners. It would also be worth reading our unbiased tuning articles to get a full grasp of the benefits and drawbacks of each modification.

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We really like hearing from our readers, and hearing about which tuning parts were the most effective for them, it helps us improve our recommendations and articles to reflect current trends in modifications and ensures that our Duratec 37 guides and tips are kept up to date.

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This article is flagged for an update, so please pass on specific tips below that I can include. All articles, and content was written by me, Waynne Smith TorqueCars founder. Some outlines are just too general so I appreciate your feedback and suggestions. This entry was filed under Ford. You can leave a response below or join our forum to discuss this article and car modification in detail with our members.

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