Modding upgrading and tuning the GM GM LS1 engine!

Modifying and improving: "GM LS1 Modifications"

GM LS1 Modifications Guide

How to modify and upgrade the GM GM LS1

"Comprehensive guide to performance parts and tuning the GM GM LS1 engine!"

Sites like TorqueCars are frequently getting emails requesting info on how to improve the GM LS1 from people inquiring about getting more power from the GM LS1 and wanting to know what are the best GM LS1 upgrades. So let us look into GM GM LS1 tuning mods and outline the best mods that work on this great engine and point out some frequent tuning mistakes along the way.

The GM GM LS1 are popular tuning projects and with carefully picked motorsport tuning mods like ECU maps, turbo kits and camshafts you will definitely maximize your driving pleasure.

This pages aim is review GM LS1 tuning and point out the ultimate mods that work.

When talking about the best parts for your GM LS1 engine, we are going to concentrate on the mods that give the biggest return for your cash.

GM LS1 induction kits

Improving air intake on the GM LS1

You need air matched to fuel for an engine to work. If there is insufficient fuel then it will run lean, if there is not enough air it runs rich sapping 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 Forcing fuel and air into each cylinder is vital to any engine modification task.

It is not unusual that there's a limitation in the air flow sensor (AFM/MAF/MAP) on the GM LS1 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 was restricting performance at a much lower level.

Air Intake manifolds flow the air during the suck phase from the air cleaner and allow it to be drawn into the engine and mixed with fuel.

Design and rate of flow of the Headers can make a noticeable effect on to fuel mixing and power on the GM LS1.

Commonly we find the intake headers are needing a performance upgrade, although some makers provide fairly well optimized intake headers.

Big valve conversions on the GM LS1, doing a bit of GM LS1 port enlargement and head flowing will also increase bhp and torque, and significantly will permit raising the bhp and torque increase on other tuning parts.

GM LS1 performance cam tips.

Each engine responds better to extreme cam durations so set your engine up on a rolling road.

The ecu map and injectors and fuel pump also have an effect on the torque gains you'll hit.

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 GM LS1 can be made from camshaft upgrades. Changing the camshaft profile alters the intake and exhaust durations on the engine and can dramatically change the power band and power output.

NB: Fast road camshafts tend to bump the power across the rev band, you could drop a little low down torque but top end will be lifted.

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

A Race camshaft won't do well if driving around busy urban areas.

You should ideally optimize your engines power to your driving style so for a typical daily driver stick with a shorter duration GM LS1 camshaft

Stage 1, 2 and 3 mods for the GM LS1

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 GM LS1 parts:

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

Stage 2 GM LS1 parts:

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

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

Stage 3 GM LS1 parts:

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

The GM LS1 units make great tuning projects and we're happy to report there are increasing numbers of modifications and tuning parts out there.

Remaps will help fully realize the full potential of all the upgrades you've done to your GM LS1.

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 usually differs on the upgrades you've carried out and the condition of your engine.

Turbo modifications on the GM LS1

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 GM LS1.

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 your car has forced induction upgrades are giving better power gains and you will discover turbo engines are built using uprated components.

However you will find an engines have limits

Research these restrictions and fit higher quality crank and pistons to survive the power.

We see many people spending a lots of money on turbo upgrades on the GM LS1 only to have the GM LS1 catastrophically fail when it's used on the roads.

Bigger turbo chargers commonly experience no power at low rpm, and little turbo chargers spool up quickly but do not have the peak rpm power band gains.

In recent times the selection of turbo units is always evolving and we now see variable vane turbo units, permitting the vane angle is altered according to speed to lower lag and increase top end performance.

Twin scroll turbo units divert the exhaust flow into two channels and push these at differently angled 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 more complex to configure. We have this in depth look at twinchargers if you want to read more.

Tips about fuel supply on the GM LS1

You will need to ensure that the engine is not starved of fuel so will have to increase the fuelling when you start going beyond 20% of a power hike. Most tuners we speak with say to be generous with your flow rate on the injectors.

The rule of thumb is to add 20% capacity when buying an injector, helps cope with injector deterioration and affords a little 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 GM LS1 performance exhaust upgrades

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

On most factory exhausts you'll find the exhaust flow rate is still good 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.

Do not go with the largest exhaust you can buy you'll 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 catalyst installed, so adding a faster flowing high performance alternative will help avoid this restriction.

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

Faults issues and things to look out for on the GM LS1

Like most engines an GM LS1, 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 GM LS1, failure to do this will exacerbate engine wear, on a tuned GM LS1 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 GM LS1 why not pop over to the forums at TorqueCars where you can chat about GM LS1 tuning options and read about others projects who may be planning to do similar modifications on their GM LS1.

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