Modding tuning and best performance upgrades on the GM Family 1 engine!

Discover "Family 1 Modifications"

How to modify and upgrade the GM Family 1

"Comprehensive guide to performance tuning the GM Family 1 engine!"

Our friends at TorqueCars are always getting emails requesting info on how to improve the Family 1 from people inquiring about getting more power from the Family 1 and wanting to know what are the things tuners are recommending when it comes to Family 1 mods that work. So let us look into GM Family 1 tuning mods and outline the best modifications on this great engine and point out some problems along the way.

Therefore we consider Family 1 tuning and summarise the optimum modifications for your car. GM Family 1 are good project engines and with the right sports parts like remaps, turbo upgrades and camshafts you will positively increase your driving experience.

Just because particular tuning parts are popular with Family 1 owners it doesn't mean it is good, we will focus on the best tuning parts that will give your Family 1 the best power gain for you spend.

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'.

Family 1 induction kits

Improving air intake on the Family 1

You need air matched to fuel for an engine to work. If there is not enough fuel then it will run lean, if there is too little air it runs rich losing power which risks damage to the Family 1. We'll pick up on fuelling later in this article but for now we shall look at air supply.

So Forcing more air and fuel into your Family 1 is the aim to any tuning project.

You'll commonly see there's a limitation in the air flow sensor MAP/MAF/AFM on the Family 1 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 was restricting power at a much lower level.

Engine intake manifolds transmit the during the engines suck phase from the air cleaner and allow it to be drawn into the engine cylinders with fuel for the squish phase.

Structure and rate of flow of the Intake can make a large difference to to fuel atomisation on the Family 1.

I usually find air intake manifolds are needing motorsport parts, although some OEM provide fairly well optimized air intake manifolds.

Adding a Family 1 larger valve kit, doing some Family 1 port enlargement and head flowing will also increase torque, the fantastic side effect is it will give you a better torque increase on other mods.

Family 1 performance cam tips.

Different Family 1 engines respond better to different cam durations check your engine on a rolling road.

The ecu map and fuel pump and injectors also will say much on the bhp gains you'll hit.

Longer valve 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 Family 1 can be made from cam upgrades. Changing the cam profile alters the intake and exhaust durations on the engine and can dramatically change the power band and power output.

NB: Fast road cams normally increase the bhp throughout the rpm range, you could sacrifice a little bottom end power but the top end will be higher.

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

In a daily driver you need to optimize your torque band to your usage of the car.

You'll never find a Family 1 Race camshaft is a pleasure to live with when in heavy traffic.

Stage 1, 2 and 3 mods for the Family 1

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 Family 1 parts:

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

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

Stage 2 Family 1 parts:

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

Stage 3 Family 1 parts:

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

The Family 1 engines make great tuning projects and we note that there is a lot of upgrades and tuning parts about.

ECU flashing should help to to establish the full potential of all the upgrades you've done to your Family 1.

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 often rely on the upgrades you've done and the condition of your engine.

Turbo modifications on the Family 1

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 Family 1.

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

When your car is turbocharged, upgrades are giving better power gains and most turbocharged engines use better components.

However you'll find engines will have power limits

See where you'll find these restrictions and fit better quality components to utilize the power.

It's not unheard of car owners spending a lots of money on turbo charger upgrades on the Family 1 only to experience the car explode soon after it's used in anger.

Big turbo units often experience a bottom end lag, and small turbo units spool up more quickly but do not have the high rpm bhp gains.

In the last 10 years the selection of turbochargers is always moving on and we commonly find variable vane turbochargers, allowing the vane profile is altered according to speed to lower lag and increase top end bhp.

Twin scroll turbochargers divert the exhaust gases 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 and torque gains, although more difficult to get working. We have this feature on twinchargers if you want to read more.

Tips about fuel supply on the Family 1

When you raise the bhp and torque you will need to pay attention to to the fuel system.

More bhp and torque needs more fuel. Experienced mechanics will tell you to over specify your flow rate on the injectors.

The accepted safe increase is to add another 15% 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 Family 1 performance exhaust upgrades

You only need to to boost your exhaust system with an upgraded one is if your exhaust is actually creating a restriction.

On most factory exhausts you should find that 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 increase the flow of air through the engine.

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

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

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

Faults issues and things to look out for on the Family 1

Like most engines an Family 1, 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 Family 1, failure to do this will exacerbate engine wear, on a tuned Family 1 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 Family 1 why not pop over to the forums at TorqueCars where you can chat about Family 1 tuning options and read about others projects who may be planning to do similar modifications on their Family 1.

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