Modding tuning and best performance upgrades on the Ford Duratec 35 engine!

Tuning guide "Duratec 35 Modifications"

Duratec 35 Modifications Guide

How to modify and upgrade the Ford Duratec 35

"Comprehensive guide to tuning the Ford Duratec 35 engine!"

Our friends at TorqueCars are regularly getting emails about how to improve the Duratec 35 from people wanting to know what are the best Duratec 35 power upgrades. So let us look into Ford Duratec 35 parts and outline the best modifications on this great engine and point out some common pitfalls along the way.

The Ford Duratec 35 are fantastic to work on and with the ultimate upgrades like remaps, turbo upgrades and camshafts you will substantially enhance your driving pleasure.

In this article we outline options for your Duratec 35 tuning and highlight the best modifications for your car.

Just because particular modifications are popular with Duratec 35 owners it doesn't mean its worth having, we will focus on the greatest modifications that will give your Duratec 35 the best power gain for you money.

Without us subscribing to the popular myth of 'if it's shiny and makes more noise it must be good' you seem to get in many tuning magazines and on car forums'.

Duratec 35  induction kits

Improving air intake on the Duratec 35

You need fuel and air for an engine to work. If there is too little fuel then it will run lean, if there is too little air it runs rich resulting in lost power . We'll pick up on fuelling later in this article but for now we shall look at air supply.

So the fundamental goal to any tuning job to push air and fuel into each cylinder but this has a knock on effect with the air flow sensor.

It is not unusual that there's a limit in the air flow sensor AFM/MAF on the Duratec 35 when considerably more air is being pulled into the engine.

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

The intake plenum transmit the during the engines suck phase from the air cleaner and allow it to be drawn into the engine cylinders.

Design and rate of flow of the Intake headers can make a big improvement to fuel engine efficiency on the Duratec 35 .

It's not uncommon that air intake manifolds are needing an upgrade, although a few OEM provide reasonably good air intake manifolds.

Fitting big valve kits, doing some Duratec 35 port enlargement and head flowing will also boost torque, and as an added benefit will give you increasing the torque increase on other tuning mods.

Duratec 35 performance cam tips.

Some Duratec 35 engines respond better to mild cam durations so view each engine as unique.

The ECU mapping and injectors and fuel pump also have an effect on the bhp gains you'll hit.

Extending exhaust or intake durations can alter the bhp 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.

Significant air intake, and exhaust improvements on the Duratec 35 can be made from camshaft upgrades. Changing the camshaft profile alters the intake and exhaust durations on the engine and can dramatically change the bhp and power output.

NB: Fast road camshafts usually increase the bhp throughout the rev range, you may lose a little low end torque but your top end will be higher.

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

A Motorsport and race camshaft makes it harder when driving around busy urban areas.

You should ideally match your torque band to your preferences so for a car used daily stick with a fast road Duratec 35 camshaft

Stage 1, 2 and 3 mods for the Duratec 35

Before we break the best tuning upgrades down into stages of tune, let's list the most effective tuning upgrades for you.

  1. Suspension Upgrades - always improve your cars handling
  2. Brake Upgrades - Even before adding power improve those brakes
  3. Intake - make sure the intake is not restricted, use filters and intake upgrades to improve this
  4. Exhaust - as with 3 ensure there is not restriction in the exhaust, cats are the usual bottleneck
  5. Tunes - remapping, piggyback ECU's and aftermarket ECU's can all make decent gains
  6. Fuelling - when you've increased power you'll need to match this with more fuel
  7. Turbo upgrades - Improving the intake with a large turbo and better flowing intercooler will be the biggest power gain you'll see (but one of the most complex).

This video guide to tuning cars is a great starting point to work from in your project.

Stage 1 Duratec 35 parts:

Panel air filters, Fast road camshaft, Intake headers, Drilled & smoothed airbox, Sports exhaust manifold, Remaps/piggy back ECU.

Stage 2 Duratec 35 parts:

Sports catalyst & performance exhaust, high flow fuel injectors, induction kit, Ported and polished head, Fast road cam, fuel pump upgrades.

Tuning tips and articles Engine tuning Transmission tuning Care care Intake & exhaust mods Improve handling Forums

Stage 3 Duratec 35 parts:

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

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

ECU flashing allows a tuner to fully realize the full potential of all the upgrades you've done to your Duratec 35 .

You will typically expect to see gains of approximately 20-30% more power on turbocharged vehicles and you can expect to see around 15% on NASP engines, but the outcome often depend much on the upgrades you've carried out and the condition of your engine.

Turbo modifications on the Duratec 35

To get a turbo working on a NASP engine there is a lot involved, from lowering compression ratio to improved fuel supply and mapping, so we have found a great guide to helpavoid the common pitfalls or end up with an unfinished project because you were not told what you were getting into by doing this on the Duratec 35 .

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

If a car has a turbocharger upgrades are simpler to install and you will discover turbocharged engines are built with better components.

There are reliable limits for every engine, with some being very over engineered and some only able to handle stock power

See where you'll find these limitations and install higher quality components to cope with the power.

It's not unheard of people spending a loads on turbocharger upgrades on the Duratec 35 only to watch the Duratec 35 go up in smoke just after it's used on the roads.

Bigger upgraded turbochargers commonly suffer no power at low rpm, and low capacity turbochargers spool up really quickly but don't have the top end bhp gains.

In recent times the selection of turbo chargers is always developing and we commonly find variable vane turbo chargers, permitting the vane profile is altered according to speed to lower lag and increase top end torque.

Twin scroll turbo chargers divert the exhaust flow into a couple of channels and push these at differently angled vanes in the turbo. They also improve the scavenging effect of the engine.

Beefing up the air intake by adding a supercharger or additional turbo will help you achieve very large bhp gains, although harder to setup. We have this article on twincharging if you want to read more.

Tips about fuel supply on the Duratec 35

Don't forget to look at the fuel delivery when you are increasing the torque - it makes the car more thirsty. We strongly recommend you to over specify your injector capacity.

As a rule of thumb add 20% capacity when buying an injector, this takes into account injector deterioration and gives a bit of spare capacity should the engine require more fuel.

Don't forget that different fuel grades will usually require different settings, a high octane fuel will burn more efficiently than lower octane fuel for example. A car will trim fuel supply to keep within the ideal air fuel mix but at the extreme ends you may need to adjust your injector capacity, or the mapping or you'll get flat spots and potential lean or rich fuel issues..

Recommended Duratec 35 performance exhaust upgrades

The only time you should look to increase your exhaust system with an upgraded one is if your exhaust is actually creating a restriction.

On most factory exhausts you'll find the exhaust flow rate is ok even on modest power gains, but on a serious tuning project with a big boost in power you will certainly need to get a better flowing exhaust.

Note that with the biggest exhaust you can source this will slow the exhaust rate - the best for power gains are usually between one and a half to two and half inches. Your exhaust design, the bend angles and construction are what have more effect on flow rates than your pipe width to a certain extent. So the exhaust design is a big factor.

Usual exhaust restrictions can be traced to the emissions filters installed, so adding a faster flowing race alternative will help avoid this restriction.

Cat bypassing (NB:catalysts reduce harmful engine emissions) is illegal in most countries and regions.

Faults issues and things to look out for on the Duratec 35

Like most engines an Duratec 35 , should have few issues if it gets properly serviced and looked after.

We cannot stress enough the need for oil changes with the correct grade of oil on the Duratec 35 , failure to do this will exacerbate engine wear, on a tuned Duratec 35 this is more important than ever and close attention should be paid to your maintenance schedule.

If you are interested in learning more or getting impartial tuning advice for your Duratec 35 why not pop over to the forums at TorqueCars where you can chat about Duratec 35 tuning options and read about others projects who may be planning to do similar modifications on their Duratec 35 .

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