Modding upgrading and tuning the Toyota 1ZR engine!

Discover "1ZR Modifications"

How to modify and upgrade the Toyota 1ZR

"Comprehensive guide to tuning the Toyota 1ZR engine!"

TorqueCars are frequently seeing threads requesting information on how to improve the 1ZR from people wanting to know what are the best tips on 1ZR upgrades. So let us look into Toyota 1ZR modifications and outline the best mods that work on this great engine and point out some potential pitfalls along the way.

Our aim here is to consider 1ZR tuning and highlight the best modifications. Toyota 1ZR make awesome project engines and with the ultimate performance modifications like ECU maps, turbo kits and camshafts you will improve your driving pleasure.

Just because particular parts are are common on 1ZR it doesn't mean it is good, instead we will concentrate on the best parts that will give your 1ZR the biggest power gain return for your cash.

Without us subscribing to the misaprehension 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'.

1ZR induction kits

Improving air intake on the 1ZR

You need air and fuel for an engine to work. If there is insufficient fuel then it will run lean, if there is a lack of air it runs rich losing 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 Feeding air into the 1ZR engine is the aim to any performance tuning task.

It is common that there is a limit in the air flow sensor MAP/MAF/AFM on the 1ZR when considerably more air is being drawn into the engine.

When tuning you may well find you need to get an air sensor or flow meter capable of upto 4 bars to cope with quite large power gains, whereas the OEM air sensor limited torque at a much lower level.

Engines intake headers carry the on the suck phase from the filter and allow it to be sucked into the engine cylinders.

Structure and rate of flow of the Headers can make a big improvement to fuel engine efficiency on the 1ZR.

It's not uncommon that plenum chambers are ripe for a performance upgrade, although a few car makers provide reasonably well designed plenum chambers.

Fitting big valve kits, doing some port work and head flowing will also improve bhp, and as an added benefit will permit an improved bhp increase on other modifications.

1ZR performance cam tips.

Different 1ZR engines respond better to mild cam durations so set your engine up on a rolling road.

The engine timing and injectors and fuel pump also have a large bearing on the bhp gains you'll make.

A longer valve duration 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 1ZR can be made from cam upgrades. Changing the cam profile alters the intake and exhaust durations on the engine and can dramatically change the engines power and power output.

NB: Fast road cams usually bump the bhp and torque across the rpm band, you could sacrifice a little low end power but the high end rpm power will be better.

Motorsport cams, 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 and race camshaft won't do well if driving around busy urban areas.

You should ideally match your bhp range to your typical driving style so for a daily driver stick with a mild fast road 1ZR camshaft

Stage 1, 2 and 3 mods for the 1ZR

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 1ZR parts:

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

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

Stage 2 1ZR parts:

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

Stage 3 1ZR parts:

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

Review your options and then find your modifications and set yourself a power target to avoid expensive mistakes.

Mapping allows a tuner to fully realize the full potential of all the parts you've done to your 1ZR.

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 parts you've carried out and the condition of your engine.

Turbo modifications on the 1ZR

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 1ZR.

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.

When your car has a turbo already fitted modifications are more reliable and you will discover turbo engines will have strengthened components.

However every engines will need better parts at higher power limits

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

It's not unheard of car owners spending a lots of money on turbo upgrades on the 1ZR only to experience the 1ZR catastrophically fail on it's first outing after it's been finished.

Big upgraded turbo chargers commonly suffer no power at low rpm, and low capacity turbo chargers spool up really quickly but won't have the top end bhp gains.

We are pleased that 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 performance.

Twin scroll turbo units divert the exhaust flow into two channels and direct these at differently profiled 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 gains, although more difficult to setup. We have this article covering twinchargers if you want to read more.

Tips about fuel supply on the 1ZR

Don't omit to increase the fuel system when you are increasing the bhp and torque - it makes the car more thirsty. It is important to be generous with your injector capacity.

The accepted safe increase is to add 20% to the flow rate when specifying an injector, this allows for injector deterioration and allows some 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 1ZR performance exhaust upgrades

Only look to increase your exhaust system with an upgraded one is if your current exhaust is actually creating a flow problem.

On most factory exhausts you'll see the exhaust flow rate is still 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 balance 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 great deal of the flow rate and end up sapping power and torque.

Typically exhaust restrictions can be located the emissions filters installed, so adding a higher flowing 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 1ZR

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

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