The Lowdown on "S-Tec Modifications"

How to modify and upgrade the Chevrolet S-Tec

"Comprehensive guide to tuning the Chevrolet S-Tec engine!"

Ever pondered on how to give your Chevrolet driving experience a boost? If you're curious about the best upgrades for your Chevrolet S-TEC engine, you're in for a treat. Join me as we explore the world of modifications that'll turn your Chevy into a performance gem without emptying your pockets.

The S-TEC engine, a series of engines from Chevrolet, is not just an engine; it's the powerhouse of your vehicle, ready to elevate your daily drives.

Picture this: the S-TEC humming under the hood of your Chevy Aveo or Optra, ready to add a touch of excitement to every turn.

Now, let's get into the details because, let's face it, that's where the magic happens.

The S-TEC may not be the biggest engine, but it packs a punch with its power figures tailored to the specific model. With a focus on efficiency and performance, the S-TEC ensures a dynamic and responsive driving experience.

Why am I, your car club companion, diving into the S-TEC? Because we're not just here for a casual chat; we're here to guide you through the maze of modifications and upgrades. And the best part? We're on a mission to make your S-TEC-powered Chevy roar without causing financial stress.

So, grab your tools because the next part of our adventure is about turning that Chevrolet into a performance masterpiece.

It's not just about saving time; it's about making every drive with your S-TEC a thrilling and enjoyable journey. Stay tuned, and let's elevate that Chevy experience together!

Forums like the one at TorqueCars are regularly getting emails about how to improve the S-Tec from people inquiring about getting more power from the S-Tec and wanting to know what are the best tips for S-Tec mods that work. So let us look into Chevrolet S-Tec modifications and outline the best upgrades on this great engine and point out some frequent tuning mistakes along the way.

Here we outline options for your S-Tec tuning and provide tips on the premier modifications. Chevrolet S-Tec great bases for a tuning project and with the ultimate sports parts like remapping, turbo improvements and camshafts you will substantially maximise your driving pleasure.

The greatest S-Tec upgrades on an engine are usually the ones that give the best power gain for your hard earned cash.

We won't be swayed by popular S-Tec upgrades, they need to be cost effective.

Improving air intake on the S-Tec

You need fuel and air for an engine to work. If there is insufficient fuel then it will run lean, if there is not enough air it runs rich resulting in lost 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 primary aim to any engine performance tuning task to pull air into each cylinder but this has a knock on effect with the air flow sensor.

It is not unusual that there is a limit in the air flow sensor AFM/MAF on the S-Tec when a lot more air is being pulled into the engine.

We note 4 bar air sensors coping with quite large power gains, whereas the OEM air sensor was restricting power at a much lower level.

Air Intake manifolds take the during the engines suck phase from the air filter and allow it to be fed into the engine and mixed with fuel.

Design and flow characteristics of the Intake headers can make a big change to fuel mixing and power on the S-Tec.

We often see air intake manifolds are needing aftermarket tuning parts, although a few manufacturers provide reasonably well designed air intake manifolds.

Adding a S-Tec larger valve kit, doing a bit of port matching and head flowing will also increase power, this will give you an improved power increase on other parts.

S-Tec performance cam tips.

Different S-Tec engines respond better to more or less aggressive cam durations check your engine on a rolling road.

The engine timing and fuelling also have an effect on the torque gains you'll get.

Longer valve durations 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.

Altering your S-Tec camshaft will make a dramatic difference to the engine engines power. Choosing a higher performance camshaft profile raises the engines power accordingly.

NB: Fast road cams tend to raise the torque throughout the rev range, you might lose a little low down torque but top end will improve.

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

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

I'd be gobsmaked if you find a S-Tec Motorsport and race cam is a pleasure to live with when driving in heavy traffic.

Stage 1, 2 and 3 mods for the S-Tec

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 S-Tec parts:

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

Stage 2 S-Tec parts:

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

Stage 3 S-Tec parts:

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

ECU flashing will help fully realize the full potential of all the mods you've done to your S-Tec.

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 your results usually differs on the mods you've fitted and the condition of your engine.

Turbo modifications on the S-Tec

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 S-Tec.

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.

If an engine has forced induction modifications are going to net you a larger power gain and most turbo charged engines are made using more solid components.

However engines have weakspots

Research these restrictions and fit better quality components to survive the power.

We've seen people spending a loads on turbo upgrades on the S-Tec only to experience the motor catastrophically fail soon after it's been enthusiastically driven.

Big turbo chargers tend to experience low end lag, and smaller turbo chargers spool up more quickly but do not have the top end power band gains.

In the last 10 years the choice of turbochargers is always improving and we now see variable vane turbochargers, permitting the vane profile is altered according to speed to lower lag and increase top end bhp and torque.

Twin scroll turbochargers divert the exhaust flow into 2 channels and flow these at differently angled vanes in the turbocharger. 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 and torque gains, although more challenging to configure. We have this article on twincharging if you want to read more.

Tips about fuel supply on the S-Tec

You will need to ensure that the engine is not starved of fuel so need to pay attention to the fuelling when you start going beyond 20% of a bhp hike. At this point we flag up the need to be generous with your injectors flow rate.

The rule of thumb is to add 15% capacity when fitting an injector, this takes into account injector deterioration and gives a little spare capacity should the engine need 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 S-Tec performance exhaust upgrades

You should look to boost your exhaust system with an upgraded one is if your exhaust is actually causing a restriction.

On most factory exhausts you'll find the exhaust flow rate is 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 gases through the engine.

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

Usual exhaust restrictions can be located the emissions filters installed, so adding a faster flowing high performance alternative will help avoid this restriction.

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

Faults issues and things to look out for on the S-Tec

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

We need your help to complete and improve this page, so do give us your feedback in the comments box below.

We want to know your experiences with mods on your S-Tec, it helps us improve our tips and keeps us current so please use the comments box to drop a tip.

This entry was posted under Makes and Models. Tags: Chevrolet, engine
You can leave a response below or join our forum to discuss this article and car modification in detail with our members.

If you liked this page please share it with your friends, drop a link to it in your favourite forum or use the bookmarking options to save it to your social media profile.

Check out TorqueCars new YouTube channel, and see their awesome new content...