Modding tuning and best performance upgrades on the Toyota 3ZZ/4ZZ engine!

Tuners tips on "3ZZ/4ZZ Modifications"

3ZZ/4ZZ Modifications Guide

How to modify and upgrade the Toyota 3ZZ/4ZZ

"Comprehensive guide to performance tuning the Toyota 3ZZ/4ZZ engine!"

TorqueCars are regularly getting posts asking about how to improve the 3ZZ/4ZZ from people wanting to know what are the best tips on 3ZZ/4ZZ modifications. So let us look into Toyota 3ZZ/4ZZ tuning mods and outline the best upgrades on this great engine and point out some potential pitfalls along the way.

Our aim here is to review 3ZZ/4ZZ tuning and highlight the ultimate upgrades. Toyota 3ZZ/4ZZ make awesome project engines and with carefully chosen sports modifications like remaps, turbo improvements and camshafts you will greatly increase your driving opportunities.

The ultimate 3ZZ/4ZZ modifications on an engine are sensibly the ones that give the best power gain for your hard earned cash.

We won't be swayed by popular 3ZZ/4ZZ modifications, they need to be cost effective.

3ZZ/4ZZ induction kits

Improving air intake on the 3ZZ/4ZZ

You need air and fuel for an engine to work. If there is not enough 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 Getting fuel and air into your 3ZZ/4ZZ is vital to any engine tuning task.

You'll commonly see there is a limitation in the air flow sensor AFM/MAF on the 3ZZ/4ZZ when considerably more air is being pulled into the engine.

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

Headers flow the during the engines suck phase from the intake filter and allow it to be drawn into the engine and mixed with fuel.

The size of bore and shape and rate of flow of the Headers can make a big effect on to fuel engine efficiency on the 3ZZ/4ZZ.

It's not uncommon that air intake manifolds are needing motorsport parts, although some makers provide fairly well optimized air intake manifolds.

Fitting big valve kits, carrying out port work and head flowing will also raise power, and importantly will give you an improved power increase on other upgrades.

3ZZ/4ZZ performance cam tips.

Some 3ZZ/4ZZ engines respond better to extreme cam durations than others.

The ecu map and injectors and fuel pump also will make differences on the torque gains you'll make.

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.

The camshaft profile plays a big part in the engines power output so camshaft upgrades make quite a large difference. The intake and exhaust durations will alter depending on the chosen camshaft profile, so large bhp gains are on offer for camshaft upgrades.

NB: Fast road camshafts tend to bump the bhp and torque through the rpm range, you might lose a little low down bhp but high end rpm power will be lifted.

Competition camshafts, bump the high end rpm power band but as a result the car will not idle smoothly and low end power nearly always suffers.

A Motorsport camshaft will just annoy you whilst driving around busy urban areas.

You should ideally match your bhp range to your cars usage so for a daily driver stick with a mild fast road 3ZZ/4ZZ camshaft

Stage 1, 2 and 3 mods for the 3ZZ/4ZZ

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 3ZZ/4ZZ parts:

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

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

Stage 2 3ZZ/4ZZ parts:

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

Stage 3 3ZZ/4ZZ parts:

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

Review your options and then source your mods and set yourself a power target to avoid expensive mistakes.

ECU mapping allows a tuner to release the full potential of all the mods you've done to your 3ZZ/4ZZ.

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 mileage will depend much on the mods you've applied and the condition of your engine.

Turbo modifications on the 3ZZ/4ZZ

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 3ZZ/4ZZ.

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 an engine has a turbo already fitted tuning mods are more reliable and we find turbo engines will have more solid components.

However you will find an engines have limits

Research these restrictions and fit better quality crank and pistons to handle the power.

It's not unheard of people spending a loads of money on turbocharger upgrades on the 3ZZ/4ZZ only to see the engine catastrophically fail soon after it's first rolling road session.

Larger turbos often experience no power at low rpm, and low capacity turbos spool up really quickly but won't have the top end power band gains.

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

Twin scroll turbo units divert the exhaust flow into a couple of channels and feed these at differently profiled vanes in the turbo. They also increase 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 configure. We have this guide to twinchargers if you want to read more.

Tips about fuel supply on the 3ZZ/4ZZ

Don't miss you'll need to raise the fuelling when you are increasing the bhp - it makes the car more thirsty. Most tuners we speak with say to be generous with your injector capacity.

The rule of thumb is to add another 20% when buying an injector, this allows for injector deterioration and affords a bit of 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 3ZZ/4ZZ performance exhaust upgrades

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

On most factory exhausts you should find that the exhaust flow rate is ok 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 will certainly help air flow through the engine but do not go too wide or you could will reduce the flow rate. Stick to one and a half to two and half inches for best results.

Typically exhaust restrictions come around the filters installed, so adding a faster flowing high performance alternative will help avoid this restriction.

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

Faults issues and things to look out for on the 3ZZ/4ZZ

Like most engines an 3ZZ/4ZZ, 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 3ZZ/4ZZ, failure to do this will exacerbate engine wear, on a tuned 3ZZ/4ZZ 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 3ZZ/4ZZ why not pop over to the forums at TorqueCars where you can chat about 3ZZ/4ZZ tuning options and read about others projects who may be planning to do similar modifications on their 3ZZ/4ZZ.

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