Modding uprating the Chevrolet F18D3 engine!

Modifying and improving: "F18D3 Modifications"

How to modify and upgrade the Chevrolet F18D3

"Comprehensive guide to tuning and performance parts on the Chevrolet F18D3 engine!"

Forums like the one at TorqueCars are frequently seeing threads about how to improve the F18D3 from people inquiring about getting more power from the F18D3 and wanting to know what are the things tuners recommend when it comes to F18D3 modifications. So let us look into Chevrolet F18D3 tuning mods and outline the best modifications on this great engine and point out some common pitfalls along the way.

Let us review F18D3 tuning and show the greatest modifications for your car. Chevrolet F18D3 are popular tuning projects and with carefully picked performance parts like a remap, turbo improvements and camshafts you will really increase your driving fun.

Just because particular modifications are are common on F18D3 it doesn't mean its worth having, instead we will focus on the best modifications that will give your F18D3 the biggest power gain return for your cash.

Without us subscribing to the common 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'.

F18D3 induction kits

Improving air intake on the F18D3

You need fuel and air for an engine to work. If there is too little fuel then it will run lean, if there is a lack of air it runs rich losing power and potentially damaging the engine. 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 pull more fuel and air into your F18D3 but this has a knock on effect with the air flow sensor.

It is not unusual that there's a limitation in the air flow sensor (AFM/MAF/MAP) on the F18D3 when considerably more air is being drawn into the engine.

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

Intake manifolds take the air from the filter and allow it to be fed into the engine cylinders with fuel for the squish phase.

Design and flow characteristics of the air Intake manifold can make a noticeable effect on to fuel delivery on the F18D3.

On popular production engines intake headers are in desperate need of an upgrade, although a few manufacturers provide well optimised intake headers.

Adding a F18D3 larger valve kit, doing a bit of port matching and head flowing will also boost torque, & more importantly will raise potential for a greater torque increase on other parts.

F18D3 performance cam tips.

Different F18D3 engines respond better to mild cam durations check your engine on a rolling road.

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

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.

Significant air intake, and exhaust improvements on the F18D3 can be made from cam upgrades. Changing the cam profile alters the intake and exhaust durations on the engine and can dramatically change the bhp and power output.

NB: Fast road cams commonly push up the torque over the rev band, you might lose a little low end torque but the higher rpm power will improve.

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

In a daily driver you should ideally to match your engines power to your cars usage.

I'd be gobsmaked if you find a F18D3 Race camshaft is a pleasure to live with when in heavy traffic.

Stage 1, 2 and 3 mods for the F18D3

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 F18D3 parts:

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

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

Stage 2 F18D3 parts:

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

Stage 3 F18D3 parts:

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

The F18D3 engine blocks make great tuning projects and we see that there are quite a few choices of upgrades and tuning parts around.

Remapping should help to unlock the full potential of all the tuning mods you've done to your F18D3.

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 figures achieved will vary depending on the tuning mods you've carried out and the condition of your engine.

Turbo modifications on the F18D3

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 F18D3.

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

When an engine is fitted with a turbo parts are going to make more power and turbo engines are made with stronger components.

However engines will have power limits

See where you'll find these restrictions and install better quality crank and pistons to utilize the power.

It's not unheard of people spending a loads on turbo charger upgrades on the F18D3 only to suffer the indignity of watching the motor go up in smoke just after it's used on the roads.

Bigger capacity turbo chargers tend to experience no power at low rpm, and little turbo chargers spool up more quickly but won't have the peak rpm power band gains.

Thankfully the selection of turbo units is always moving on and we now see variable vane turbo units, permitting the vane angle is altered according to speed to lower lag and increase top end torque.

Twin scroll turbo units divert the exhaust flow into a couple of channels and flow these at differently designed vanes in the turbo. They also boost 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 get working. We have this feature on twinchargers if you want to read more.

Tips about fuel supply on the F18D3

When you lift the performance you will need to look at to the fuelling.

More performance needs more fuel. Experienced mechanics will tell you to over specify your injector capacity.

The rule of thumb is to add 20% capacity when buying an injector, helps cope with injector deterioration and gives you some 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 F18D3 performance exhaust upgrades

Only look to improve your exhaust system with an upgraded one is if your current exhaust is creating a flow problem.

On most factory exhausts you should find that the exhaust flow rate is still fine 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.

Sports exhausts can help increase the flow of air through the engine.

But if the exhaust pipe is too large, ie: it's over two and a half inches diameter, you will lose much of your flow rate and end up lacking power and torque.

The usual suspects causing problems in your exhaust flow rate can be located the emissions filters installed, so adding a faster flowing sports alternative will help avoid this restriction.

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

Faults issues and things to look out for on the F18D3

Like most engines an F18D3, 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 F18D3, failure to do this will exacerbate engine wear, on a tuned F18D3 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 F18D3 why not pop over to the forums at TorqueCars where you can chat about F18D3 tuning options and read about others projects who may be planning to do similar modifications on their F18D3.

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