Daihatsu Mira Tuning

"All you need to know about tuning the Daihatsu Mira engine!"

As many of our readers have emailed us about the Mira and recommendations on how to modify one, so we've put together this feature to go over what we feel are the primary areas which make for improvement and tuning success on this great car.

In this article we look at Mira tuning and point out the greatest upgrades. Daihatsu Mira offer good returns when tuned and with carefully chosen modified upgrades like remaps, turbo kits and camshafts you will really maximise your driving opportunities.

History of the Mira Engine

L55/L60 series (1980)

547 cc AB10/30/31 I2
547 cc AB35 turbo I2
617 cc AD I2

L70/L80 series (1985)

547 cc EB I3
796 cc ED-10A I3
847 cc ED-10 I3

L200 series (1990)

547 cc EB I3
659 cc EF I3
847 cc ED10 I3

L500 series (1994)

659 cc EF-CL/FL/KL I3
659 cc EF-EL 12-valve I3
659 cc EF-JL 12-valve turbo I3
659 cc JB-EL I4
659 cc JB-JL turbo I4
847 cc ED-10/20 I3
847 cc ED-DE 12-valve DOHC I3

L700 series (1998)

659 cc JB-EL I3 (L700/710)
847 cc ED-DE I3
989 cc EJ I4 (L701/711)

L250 series (2002)

659 cc EF I3
989 cc EJ I3

L275 series (2006)

658 cc KF I3
996 cc 1KR-FE I3

Tuning the Daihatsu Mira and best Mira performance parts.

Best Mira tuning mods

When talking about the best modifications for your Mira engine, we are going to concentrate on the modifications that provide the best value for money.

Please watch our video which covers the 5 principles of tuning your Mira. Be sure to keep up with our latest YouTube content and subscribe.

Best mods for your Mira

1. Tunes - engine tuning/remapping provides the most power for the money, aftermarket ECUs, and Tuning boxes are all alternatives.
2. Fast road cams are are often the best upgrade for an engine, but they must be setup by someone who knows what they are doing and they are not always easy to source but you might find a local firm to regrind a stock camshaft.
3. Intake Mods and Sports Exhausts - Note that on their own these mods won't ADD POWER in most cases, but they can help enhance power after other mods by removing the restriction.
4. Turbo upgrades - forced induction is the most efficient approach to increase air supply, allowing you to burn more fuel and make more power. Although one of the most costly upgrades it does provide the largest gains.
5. Head work - The goals of porting and flowing the head are to get air flowing into the engine while removing flow restrictions and turbulence.

Mira Tuning Stages

Typical stage 1 mods often include: Remaps/piggy back ECU, Panel air filters, Drilled & smoothed airbox, Fast road camshaft, Intake manifolds, Sports exhaust manifold.

Typical stage 2 mods often include: Sports catalyst & performance exhaust, high flow fuel injectors, Ported and polished head, Fast road cam, induction kit, fuel pump upgrades.

Typical stage 3 mods often include: Adding or Upgrading forced induction (turbo/supercharger), Internal engine upgrades (head flowing porting/bigger valves), Competition cam, Crank and Piston upgrades to alter compression, Twin charging conversions, Engine balancing & blueprinting.

Mira Camshaft Upgrades

Fast road cams come into their own at top end power so are more suited to petrol engines, than diesel ones. In most cases you will see top end power benefits through performance camshafts on most engines. So altering your Mira camshaft will make a difference to the engine power band. Choosing a higher performance camshaft profile raises the torque accordingly.

Fast road cams commonly boost the performance throughout the rpm band, you may sacrifice a little low end bhp but higher rpm power will be higher.

Motorsport and race cams, boost the higher rpm power band but as a result the car will not idle smoothly and low end power nearly always suffers.

In a road car you should ideally to optimize your torque band to your usage of the car.

You'll never think that a Mira Motorsport camshaft is a pleasure to live with when driving around busy urban areas.The low end idle will typically be lumpy and irregular, and this is something you'd notice on a track when you drive in the upper third of the rpm band, but on roads this is a serious issue and we've heard from lots of drivers regretting their decision to install a more extreme competition cam profile to their engine.

Different Mira engines respond differently primarily due to the airflow when cams are fitted depending on the cam being more aggressive cam durations so view each engine and camshaft as unique due to manufacturing tolerances and quality variations so set your engine up on a rolling road.

The engine timing and fuel delivery and fuel pump and injectors also have a large bearing on the power gains you'll achieve.

Longer valve durations can adjust the power curve, and on most engines there are some advantages to extending the intake or exhaust durations and valve lift.

ECU Mapping Improvements for the Mira

A remap will help unlock the full potential of all the modifications you've installed on your Mira.

(Sometimes chip tuning the ECU is not an option, so an aftermarket ECU is the route to take, and many of these will outperform factory ECU's but ensure it has knock protection and that you get it correctly setup.) It will usually give around 30% more power on turbocharged vehicles and you can expect to see around 15% on NA (naturally aspirated) engines, but figures achieved usually rely on the modifications you've done and the condition of your engine.

Air Flow improvements on the Mira

Pushing air into your Mira is the whole point to any performance tuning job.

The intake plenum take the air during the suck phase from the intake filter and allow it to be fed into the engine cylinders with fuel for the squish phase.

The size of bore and shape and flow rate of the Intake manifold can make a large difference to to fuel engine efficiency on the Mira.

We often see intake are needing performance upgrades, although a few OEM provide fairly well optimized intake.

Adding a Mira big valve conversion, doing some Mira port enlargement and head flowing will also boost performance, & importantly will give you a better performance increase on other tuning mods.

Mira Turbo upgrades

NA (naturally aspirated) engines need quite a lot of work when you add a turbo, so we have a separate guide to help you take into account the pros and cons of going this route on your Mira

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

When an engine has a turbocharger upgrades are more reliable and you'll see that turbo engines are made with stronger components.

There are tuning limits for every engine, with some being over specified and some just sufficiently able to handle stock power. It is important to find these limitations and install better quality components to utilize the power.

We've seen drivers spending lots of money on turbo upgrades on the Mira only to see the Mira catastrophically fail soon after it's completed.

Bigger upgraded turbo chargers often suffer low end lag, and smaller turbo chargers spool up quickly but won't have the high rpm power band gains.

Thanks to new tech the range of turbochargers is always evolving and we commonly find variable vane turbochargers, allowing the vane angle is altered according to speed to lower lag and increase top end torque.

Twin scroll turbochargers divert the exhaust flow into two channels and push these at differently profiled vanes in the turbo charger. They also improve the scavenging effect of the engine.

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

Adding a supercharger or additional turbo will make large torque gains, although harder to install. We have this feature on twinchargers if you want to read more.

Mira Fuelling Upgrades

You will need to ensure that the engine is not starved of fuel so need to pay attention to the fuelling when you start going beyond 20% of a power increase. Boosting the fuel pressure can improve the acceleration responsiveness.Most tuners we speak with say to be generous with your flow rate on the injectors.

The accepted safe increase is to add another 20% when specifying an injector, this accounts for injector deterioration and provides some spare capacity should the engine need more fuel.

We think this one is common sense, but you'll need to match your fuel injector to the type of fuel your car uses as well.

Mira Performance Exhausts

You should look to replace your exhaust if the existing exhaust is creating a restriction in flow.

On most factory exhausts you should find that the exhaust flow rate is good even on modest power gains, but when you start pushing up the power levels you will need to get a better flowing exhaust.

Sports exhausts will certainly help air flow through the engine but avoid an exhaust that is too wide or you will choke your flow rate. Keep the exhaust pipes to around 1.5 to 2.5 inches as a rule of thumb.

For road going cars mods such as a sports catalyst pretty much remove this restriction,mainly due to it's larger size and surface area, and will effectively raise the performance to levels you would expect without having a catalyst installed, but keeps the car road legal. And will better flow due to it's higher internal surface area and design. The alternative test pipe mod or catalyst removal should be considered an off road only mod, as removing a catalyst is illegal in most territories and regions for road registered cars (and in some you can't even replace a working catalyst).

Weak spots, Issues & problem areas on the Mira

The Mira engines are generally reliable and solid as long as they are regularly serviced and maintained.

Carbon build up in the head, particularly around the valves which will sap power or create flat spots, this is a larger issue on direct injection engines but should be looked out for on all engines. We have tips on intake clean to remove carbon build up To minimize this risk only use quality fuel and don't short journeys.

Frequent oil changes are vital on the Mira, and more so when the car is modified and will help maintain the long life of the engine.

If you want to know more, or just get more pointers on Tuning your Mira engine please join us in our friendly forum where you can discuss Mira tuning options in more detail with our Mira owners. It would also be worth reading our unbiased Daihatsu tuning articles to get insights into each modification and how effective they will be.

Please help us improve these tips by sending us your feedback in the comments box below.

We appreciate people taking the time to tell us what our visitors have got up to and which parts work best for them on each model of car. We use your comments and feedback to improve the accuracy of these Mira tuning guides which get regular updates and revisions.

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This article is flagged for an update, so please pass on specific tips below that I can include. All articles, and content was written by me, Waynne Smith TorqueCars founder. Some outlines are just too general so I appreciate your feedback and suggestions. This entry was filed under Daihatsu. You can leave a response below or join our forum to discuss this article and car modification in detail with our members.

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