Modding and performance tuning parts for the GM LS2 engine!

Modifying and improving: "LS2 Modifications"

How to modify and upgrade the GM LS2

"Comprehensive guide to tuning the GM LS2 engine!"

Sites like TorqueCars often are seeing threads requesting information on how to improve the LS2 from people inquiring about getting more power from the LS2 and wanting to know what are the things tuners are recommending when it comes to LS2 modifications. So let us look into GM LS2 parts and outline the best upgrades on this great engine and point out some common pitfalls along the way.

The GM LS2 are awesome to work on and with the best uprated modifications like a remap, turbo upgrades and camshafts you will dramatically increase your driving fun.

Car Tuning Tips will provide a guide to LS2 tuning and summarise the optimum modifications for your car.

Just because particular parts are popular with LS2 owners it doesn't mean you should fit it, so we'll focus on the best parts that will give your LS2 the best value for money to power increase.

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'.

LS2 induction kits

Improving air intake on the LS2

You need air matched to fuel for an engine to work. If there is too little fuel then it will run lean, if there is insufficient air it runs rich losing power which risks damage to the LS2. We'll pick up on fuelling later in this article but for now we shall look at air supply.

So the goal to any engine performance tuning task to force fuel and air into each cylinder but this has a knock on effect with the air flow sensor.

It is not unusual that there's a restriction in the air flow sensor AFM/MAP on the LS2 when a lot more air is being drawn into the engine.

We see 4 bar air sensors coping with quite large power gains, whereas the OEM air sensor limited bhp and torque at a much lower level.

Headers transmit the on the suck phase from the air filter and allow it to be drawn into the engine cylinders.

Design and flow characteristics of the Intake headers can make a big change to fuel delivery on the LS2.

Commonly we find the air intake manifolds are improved through a performance upgrade, although a few manufacturers provide reasonably well designed air intake manifolds.

Big valve conversions on the LS2, doing some LS2 port enlargement and head flowing will also lift bhp, & importantly will give you raising the bhp increase on other parts.

LS2 performance cam tips.

Some LS2 engines respond better to different cam durations so set your engine up on a rolling road.

The ECU mapping and fuel pump and injectors also will make differences 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.

Altering your LS2 cam will make a dramatic difference to the engine power band. Choosing a higher performance cam profile raises the power band accordingly.

NB: Fast road cams commonly raise the bhp across the rpm band, you might lose a little low end power but your top end will be lifted.

Competition 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 daily driver you should ideally to match your bhp range to your preferences.

I'd be shocked if you have ever thought a LS2 Competition cam is a pleasure to live with when in heavy traffic.

Stage 1, 2 and 3 mods for the LS2

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 LS2 parts:

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

Stage 2 LS2 parts:

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

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

Stage 3 LS2 parts:

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

The LS2 power trains respond well to upgrades and thankfully there is a lot of modifications and performance parts out there.

Remaps should help to release the full potential of all the mods you've done to your LS2.

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 depend much on the mods you've carried out and the condition of your engine.

Turbo modifications on the LS2

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 LS2.

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

If an engine has forced induction tuning mods are giving better power gains and most turbocharged engines are made with uprated components.

However you'll find engines will have power limits

See where you'll find these restrictions and upgrade to more solid crank and pistons to cope with the power.

It's not unheard of tuners spending a loads on turbo charger upgrades on the LS2 only to see the whole thing literally blow up when it's completed.

Bigger capacity turbochargers often suffer no power at low rpm, and smaller turbochargers spool up much more quickly but won't have the top end bhp gains.

In recent times the market of turbochargers is always developing and we commonly find variable vane turbochargers, permitting the vane angle is altered according to speed to lower lag and increase top end torque.

Twin scroll turbochargers divert the exhaust gases into a couple of channels and flow these at differently profiled 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 power gains, although more complex to configure. We have this article on twincharging if you want to read more.

Tips about fuel supply on the LS2

You will need to ensure that the engine is not starved of fuel so should look at the fuelling when you start going beyond 20% of a bhp hike. Don't forget to be generous with your flow rate on the injectors.

The rule of thumb is to add another 15% when specifying an injector, helps cope with injector deterioration and affords 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 LS2 performance exhaust upgrades

The only time you should look to boost your exhaust system with an upgraded one is if the existing exhaust is actually causing a restriction in flow.

On most factory exhausts you'll see 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.

Please dont run with the widest exhaust you can source this will reduce the exhaust flow rate - the best exhausts 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.

The usual suspects causing problems in your exhaust flow rate can be located the emissions filters installed, so adding a better 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 LS2

Like most engines an LS2, 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 LS2, failure to do this will exacerbate engine wear, on a tuned LS2 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 LS2 why not pop over to the forums at TorqueCars where you can chat about LS2 tuning options and read about others projects who may be planning to do similar modifications on their LS2.

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