Tuning the Ford 1.25 Duratec

"Comprehensive guide to tuning and performance parts on the Ford 1.25 Duratec engine!"

We are regularly getting emails asking how to improve the 1.25 Duratec from people wanting to know what are the optimum 1.25 Duratec modifications. So let us look into Ford 1.25 Duratec parts and outline the best modifications on this great engine and point out some problems along the way.

Now we shall review and look at 1.25 Duratec tuning and point out the best modifications for your car. Ford 1.25 Duratec are awesome to work on and with the optimum tuning modifications like remaps, turbo improvements and camshafts you will really maximize your driving opportunities.

The best 1.25 Duratec upgrades on an engine are usually the ones that give the best value for money.

We won't be swayed by popular 1.25 Duratec upgrades, they need to be cost effective.

Altering your 1.25 Duratec cam will make a dramatic difference to the engine engines power. Choosing a higher performance cam profile raises the engines power accordingly.

NB: Fast road camshafts commonly increase the bhp and torque over the rev band, you may lose a little low end power but the high end rpm power will be lifted.

Competition 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 car driven daily one should, ideally, try to match your engines power to your typical driving style.

I would be surprised if you have found a 1.25 Duratec Motorsport camshaft is a pleasure to live with when driving around busy urban areas.

Different 1.25 Duratec engines respond better to different cam durations so set your engine up on a rolling road.

The ecu map and fuel pump and injectors also have a large bearing on the power gains you'll achieve.

Longer valve durations can alter the power 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.

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1.25 Duratec Tuning Stages

Stage 1 1.25 Duratec modifications: Remaps/piggy back ECU, Intake headers, Panel air filters, Sports exhaust manifold, Fast road camshaft, Drilled & smoothed airbox.

Stage 2 1.25 Duratec modifications: high flow fuel injectors, Ported and polished head, Fast road cam, fuel pump upgrades, Sports catalyst & performance exhaust, induction kit.

Stage 3 1.25 Duratec modifications: Crank and Piston upgrades to alter compression, Twin charging conversions, Internal engine upgrades (head flowing porting/bigger valves), Engine balancing & blueprinting, Competition cam, Adding or Upgrading forced induction (turbo/supercharger).

Mapping helps fully realize the full potential of all the upgrades you've done to your 1.25 Duratec.

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 usually depend much on the upgrades you've applied and the condition of your engine.

Pulling air and fuel into the 1.25 Duratec engine is the main goal to any engine modification task.

Intake manifold transmit the air from the air filter and allow it to be drawn into the engine cylinders with fuel for the squish phase.

The shape and flow rate of the Intake can make a substantial change to fuel atomisation and engine efficiency on the 1.25 Duratec.

Commonly we find the headers are in desperate need of an upgrade, although a few manufacturers provide well optimised headers.

Adding a 1.25 Duratec larger valve kit, doing some 3 or 5 angle valve jobs and porting and head flowing will also lift bhp, & importantly will allow you to get raising the bhp increase on other tuning mods.

Turbo upgrades for the 1.25 Duratec

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 1.25 Duratec

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.

When the engine has forced induction modifications are going to net you a larger power gain and most turbocharged engines are built with uprated components.

However you'll find engines will need better parts at higher power limits

See where you'll find these limitations and fit better pistons and crank to utilize the power.

We've seen people spending a lot of money on turbo upgrades on the 1.25 Duratec only to experience the whole thing literally blow up just after it's used on the roads.

Bigger capacity turbo chargers will usually experience a bottom end lag, and little turbo chargers spool up really quickly but don't have the peak end engines power gains.

Thanks to progress the range of turbos is always developing and we now see variable vane turbos, allowing the vane angle is altered according to speed to lower lag and increase top end bhp and torque.

Twin scroll turbos divert the exhaust flow into 2 channels and feed these at differently profiled vanes in the turbocharger. They also improve the scavenging effect of the engine.

You'll commonly see there is a limit in the air flow sensor (AFM/MAF/MAP) on the 1.25 Duratec when loads more air is being sucked into the engine.

You'll see that 4 bar air sensors coping with quite large power gains, whereas the OEM air sensor limited power at a much lower level.

Adding a supercharger or additional turbo will make large torque gains, although more complex to install. We have this guide to twinchargers if you want to read more.

Uprating 1.25 Duratec fuel injectors

When you improve the power you will need to uprate to the fuel delivery.

More power needs more fuel. Most tuners we speak with say to be generous with your flow rate on the injectors.

As a rule of thumb add 20% when fitting an injector, which takes into account 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 1.25 Duratec performance exhausts

You only need to to increase your exhaust if your current exhaust is actually creating a flow problem.

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

Note that with the widest exhaust you can get you'll slow the exhaust rate - the best for power gains are usually between 1.5 to 2.5 inches. It is the shape and material more than the bore size.

Typically exhaust restrictions come around the emissions filters installed, so adding a faster flowing sports alternative will help avoid this restriction.

Problems and issues to look out for on the 1.25 Duratec

The 1.25 Duratec engines, if regularly serviced and maintained, are generally very reliable and have few issues.

Regular oil changes are vital on the 1.25 Duratec, particularly when the engine has been modified and is putting down more power than the manufacturer intended.

For more information on Tuning your 1.25 Duratec engine please join us in our friendly forum where you can discuss tuning options in more detail with our 1.25 Duratec 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 1.25 Duratec 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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