Mitsubishi Evolution Lancer EVO 6 - 9 Turbo with 4G63 DOHC 16v

Dummies Guide to Vehicle Modifications!

RPW has been working on Mitsubishi Evolution Lancer Turbo’s from the day they arrived as the Galant VR4 / EVO 1 to the current EVO X. Not many businesses have been in the industry long enough like ourselves, to have had the opportunity to grow and enjoy every Evolution of the EVO Vehicles.

This has given us the ability to know and understand how they work and what makes them go best. This modification guide has been written, utilising our own experience, information from various websites and forums to provide a fairly comprehensive guide on how to power up your vehicle for maximum performance, torque and fun. This guide outlines a levels of modifications to suit the standard daily drive wanting more power, to the person wanting to do heavy track work but retain street drive-ability if necessary.

These modifications  has been researched, developed and tested by ourselves and countless EVO Owners world wide. Guaranteed to work, these represents a comprehensive and well balanced selection of parts designed for maximum gain without spending your money on items that produce no credible gains. Our experience over the past 20 years means that we have done the hard work so that you don’t have to. This guide pertains to the following model vehicles

  • Mitsubishi EVO 6
  • Mitsubishi EVO 6.5
  • Mitsubishi EVO 7
  • Mitsubishi EVO 8
  • Mitsubishi EVO 9 (4G63 DOHC 16v Mivec Engine)

All these models are essentially the same engine package with slight variations in camshaft profiles, turbine housings and in external areas with increasing levels of computer driving aids, finishing with variations in gearboxes from the bullet proof 5 speeds to the not so bullet proof 6 speed boxes. For the purpose of this guide, we will treat them all the same with reference to modifications. This guide is written for the street level enthusiast, wanting a combination of street and track duty whilst retaining the ability to drive the vehicle every day.

The EVO 9 has the added advantage of Variable Cam Timing (Mivec) on the intake camshaft which aids in improved throttle response and reducing spool up. The EVO 9 also had a better turbo which is the common turbo upgrade for the EVO 6 – 8 models.

For sure, there are more aggressive and power performing products on the market, but with increasing levels of police focus on our vehicles, the aim is to focus on modifications which retain at the very minimum, a visual inspection for legalities.

Whilst all care is taken with the following information in this guide, we recommend you speak with your tuner / installer prior to performing any work on your vehicle. We also recommend performing the modifications in the order provided, in order to maximise your gains and minimise your expenses.

Stage 1 Modifications – for the Street Driven Vehicle / Light Track Work

The summary of modifications are as listed below, read further down for more detailed break down of why these are recommended.

These fundamental upgrades will take the vehicle from the 220hp at the wheels to around the 280hp (Evo 4-8) and 300hp (Evo 9)  range with increased boost of around 20 – 22psi.

Mid range torque is the largest gain with a much punchier acceleration. Fuel economy should also be the improved.

  • Air Intake System upgrade
  • Blow off valve upgrade
  • Exhaust System upgrade
  • Fuel pump upgrade
  • Boost System control
  • Remap factory ECU

Stage 2 Modifications – for the Street Driven Vehicle /Light to Medium Track Work

This level of modifications expands upon what we class as the baseline modification as outlined in the Stage 1 guide.

This now steps it up further with more ancillary items. Horsepower will peak at around 300 – 320hp at the wheels, torque will be the largest gain over the stage 1.

Boost increased to the 25 psi range on average (Depending upon duty cycle of injectors)

  • Intercooler pipe upgrade
  • Air induction pipe between Turbo and MAF Sensor
  • Fuel Injector Upgrade
  • Wastegate actuator replacement
  • Exhaust dump pipe housing upggrade
  • Remap factory ECU

Stage 3 Modifications – for the Street Driven Vehicle /Medium to Heavy Track Work

This level of modifications expands the Stage 1 & 2 levels of modifications.

These modifications now focus primarily on mid range to high rpm power levels and are for horsepower levels in excess of 350hp at the wheels.

Fuel economy will probably drop and vehicle will no longer retain factory smoothness at idle.

  • Injector Upgrade/ Fuel Rail Upgrade
  • Turbo / Turbocharger Upgrade
  • Camshaft package upgrade
  • Intake Manifold / Throttle Body Upgrade
  • Fuel Pump Wiring & Relay Upgrade
  • Remap factory ECU
  • Plug and Play After market ECU

Air Intake System Upgrade

The stock air box on these vehicles are very effective in there own design. They don’t allow large heat soak to occur, have a large filtering area and get reasonable airflow. Our preference is to retain the stock air box and fit it with the K&N panel replacement filter which for the majority of customers, is all that you would ever require, even for high level modifications later down the track.

  • K&N Panel Replacement Air Filter – increases air flow with less restrictive filter material.
  • K&N Pod Filter Replacement – Increased heat soak but more capacity for air induction, suitable for those chasing very high horsepower levels, works well where inter-coolers are upgraded to larger units.
  • Upgraded Air Intake Scoop into stock / after market air box – allows greater airflow without heat soak issues. Can utilise a Pod filter instead of panel filter inside the air box. Usually higher costs and not always direct fitment like factory.

The intake pipe between the turbo and air box, is one more item that has been built on the basis of mass production. The pipe is not smooth and it has been shown that replacing it with a smooth silicone hose has considerable improvements in air flow. As this feeds the air into the turbine unit itself, the results are quite dramatic and are very noticeable. These also have a high cosmetic value being in shiny blue / red / black hosing.

Inter-cooler Piping Upgrade

The stock pipe work on the EVO’s are generally quite good. But the lower inter cooler pipe from the turbo to the inter cooler, for some reason, is quite restrictive.

Significant gains are found in the performance of the boost curve and throttle response by replacing this pipe with a higher flowing unit.

Replacing the balance of the inter-cooler pipes with hard pipe / improved silicone hose units has the additional benefit of improving looks and boost control, although the gains are minor.

Blow Off Valve Upgrade

The EVO vehicles came out with two types of blow off valves. Many came with the plastic units, the MR models came out with the metal unit.

The plastic based units are renowned for boost leakage once you get above 17 – 18 psi, as well as being inconsistent.

We commonly use qaulity brands like GFB, Turbosmart etc where these units are direct fitment and most importantly, are fully legal with any police inspection. Use of VTA – Vent To Atmosphere after market units can create idling / stalling issues on gear changes as well as being illegal.

Exhaust System Upgrade

Like all vehicles the factory systems are designed to keep noise levels at a very low level. There are four levels of improvements in the EVO Exhaust systems. These are

  • Cat Back Exhaust System – self explanatory. From the cat converter back, fitment of an upgraded 3″ exhausts system. This will improve power, torque and allow the motor to breath better. Increased acceleration and eagerness to rev.
  • Cat Converter Upgrade – replacement of stock with a high flowing Metallic Cat Converter. Continues to focus on improving the breathing of the vehicle. Metallic cat converters provide longer lasting benefits and are more robust than factory ceramic cat converters.
  • Front Pipe Upgrade – the stock units tend to be small in diameter and usually have nasty bends. Larger diameter piping matches the rest of the exhaust.
  • Turbo Outlet – the turbo outlet / dump pipe off the back of the turbo usually only has a 2 1/2″ outlet. After market units with larger outlets have significant flow improvements over the stock design. This will improve the boost curve tremendously.

There are plenty of great brands out on the market place that we use including Turboxs, XForce, Custom Exhaust Specialists to name a few. The main feature of all of these, is the are true 3″ systems and in a lot of cases, come with the turbo outlet section as part of the full exhaust upgrade.

There are several brand Dump Pipe Housings on the market, from Tomei, Zage to name just two of many. The units we use due to there larger diameter outlets, being a true 3″, compared to other brands being only 2 3/4″ or close to factory diameters.

Fuel Pump Upgrade & Rewire

The stock fuel pump on the evo is rated at between 80 – 160 litres per hour. Fine for a stock tune but as soon as you increase the boost level, you will be close to 100% of its duty cycle with no reserve.

The replacement of choice is either a Walbro or Duetchworks unit. These are available in sizes ranging from 255, 300 and 400 LPH. The larger sizes suitable for customers considring using E85 fuel. Being a direct bolt in unit, there are no modifications required.

With those going to Stage 3 level, upgrading of the wiring to the fuel pump is necessary. Factory wiring limits voltage to only 11 – 12v. Fitting a new relay with larger power wires, can provide a true 13.5 – 14V to the fuel pump, increasing its flow capacity by as much as 20%. This can all be hidden beneath the seat and is a necessity for those wanting in excess of 300hp at the wheels reliably.

Injector Upgrade / Fuel Rail

The stock fuel injectors on the evo lancers are fairly large to start with. There are slight variations in the models, but the standard sizes are usually the 560cc to 580cc range. Once you reach the 300hp range at the wheels, the stock injectors with the fuel pump upgrade usually reaches 90% injector cycle.

The standard upgrade is to go to at least some 750cc units, or larger 1000cc if camshafts and other mods are to be added. For those considering moving to E85 fuels, 1000cc units are recommended.

With the use of larger injectors retuning is absolutely required.

Following on with the injectors, consideration of a fuel rail upgrade is also worthwhile. Only for those going to stage 3 or higher levels of modifications. This helps in smoothing out the fuel flow and providing a larger store of fuel available to the injectors.

We normally utilise a complete package of upgraded fuel rail, injectors and fuel pressure regulator kit. Never be afraid to go overboard on the fuel system – its the heart of your vehicle.

Boost Upgrade including Waste Gate Actuator Upgrade

The EVO vehicles utilise a factory bleeder system onto the stock waste gate. A Restrictor pill restricts the volume of gases going to the waste gate, and is bled off by an electronically controlled solenoid (Or twin solenoids on some models) to raise the boost level above the waste gate actuator spring tension (Usually set to 10 psi).

There are three methods of electronically controlling the boost on the EVO. The first two methods, utilise the Factory ECU. The third method replaces this with an after market unit.

(A) Factory Boost Pill Upgrade – the simplest, cheapest and for majority of customers, most effective method. Fitment of a smaller boost pill allows the boost level to be upgraded at all rpm levels. Side effects of this method, is that because boost is always being fed to the waste gate actuator, it does bleed off slightly earlier than other methods, and does not peak as early. This system requires retuning of the factory ECU. This system is good for up to 25 psi with no side effects and is the perfect choice for daily driven vehicles for smooth power delivery.

(B) Fitment of 3 Port Boost Solenoid – again utilising the factory ECU for control of boost. The factory 2 port / boost pill set-up is replaced with an after market 3 port solenoid. By using 3 ports, boost is held off the waste gate actuator until the last possible moment, allowing the boost level to reach the desired point as early as possible. This system requires significantly more tuning of boost with the factory ECU, but provides the same level of boost control as after market units. This provides a very aggressive boost and power curve, providing that typical kick or push on acceleration as it hits peak boost. This system can allow peak boost to also be created earlier, by as much as 250 – 500 rpm over the stock set-up.

RPW utilises this method the most, why pay for something that you already have built into your vehicle from the factory.

(C) After market Electronic Boost control – there is no doubt these work well and can be very quickly and easily set-up on the vehicle. More advanced units allow up to four different boost levels, and depending upon the model, can be set-up for a stable boost curve within 10 minutes. But they do take considerable time to setup including wiring through the firewall and good value ones start around the $600 range plus fitment and tuning. For these our preference is the Greddy Profec B Spec units which don’t have complicated menu options.

Waste gate Actuator Upgrade – no matter which method you choose, at some point the factory waste gate is going to creep off and not allow a boost level of usually around 15 psi, above 5500 rpm to be maintained. The logical choice is to replace the actuator with a 1.3 / 1.5 BAR unit. This allows all of the above boost methods to work more accurately, and allows the boost curve to remain as flat as possible in the higher rpm ranges. With 3 port solenoids, this also aids in stopping oscillations in the boost curve as the tuning over compensates when above 20 psi (Depending upon turbo and exhaust choices)

Camshaft Package Upgrade

The EVO 6 – EVO 8 run nearly virtual identical camshaft profiles in stock trim. There were some EVO 7 & 8’s that did run a slightly more aggressive profile in combination with a larger turbine. The EVO 9 of course, ran the new profile with its mivec cam timing set-up.

There is a large range of camshafts on the market, but there is no denying, it is something that should be done as a package. This means doing the camshafts, valve springs and vernier camshaft gears. Even if you plan on using a small profile which does not require valve springs, still replace them anyway. Yes it is more expensive, but it provides much better safety, control and will handle high rpm / high boost use over a long time period. We also recommend whilst doing this, fitment of some ARP Head studs should be done at the same time.

RPW utilises the a range of camshaft suppliers including Camtech, BC, Crower along with quality cam gears. Proven high quality billets and profiles, expect with tuning to see large gains in horsepower and torque. As you go larger in the profiles, idle and low rpm drive ability will begin to suffer, followed by fuel economy.

For the majority of owners, going for a mild profile will provide great benefits without any serious side effects and can be tuned easily with the stock ecu / reflash.

The EVO 9 is even more responsive to camshaft upgrades and even a mild profile increase has significant results.

Intake Manifold / Throttle Body Upgrade

The stock manifolds and throttle bodies on the EVO’s all utilise a 60mm butterfly and well designed manifolds. The reality is that unless you are after very serious horsepower levels, leave the intake manifold stock. There is no doubt aftermarket manifolds can produce large gains – brands like Magnus, Hyperflow, plazamman etc not only look radically different, but enable high flow. But this gain is usually focused more on mid range and upper high rpm, with a slight loss on throttle response off boost due to the much larger plenum chambers.

For those building a more dedicated circuit racing vehicle, intake manifold upgrades can be very effective. For tight Motorkhana use or street driven (Majority) stay with the stock manifold which retains that throttle response from low rpm off boost.

When you do upgrade the intake manifold, utilising a 70mm Billet throttle body can ensure maximum airflow into the vehicle as well as enhance throttle response. RPW uses the S90 range of throttle bodies which retain fittings for the stock idle speed control motors.

Any intake manifold / throttle body upgrade will require retuning.

Turbo Manifold / Turbocharger Upgrade

There are several model turbochargers on the EVO range. The best thing about EVO’s are there instant throttle response, massive top end horsepower and the ease of which they come on boost. The EVO 6 – 8 range need to choose turbo upgrades carefully. Choosing a turbo too large, will induce large turbo lag and whilst it may make large horsepower, the loss of low rpm torque and low rpm torque, even on boost, can make the car slower in some situations.

As a rule of thumb, staying with a factory Mitsubishi turbo as an upgrade is the best way to go. The vehicle retains the stock fitment, can make large horsepower and retain low spool up. The rule of thumb is to use the turbo off the EVO 9 model, the TD05HR – 16G6C -10.5T. This turbo only slightly increases the rpm at which peak boost is produced, but has extremely strong mid range power levels and is a direct fitment, without needing to change any pipe work. This turbo can produce in excess of 300hp at the wheels, but will also enable the vehicle to be extremely competitive in all forms of motor sport.

For EVO 9 owners, having variable cam timing means a larger turbine can be fitted without inducing massive turbo lag. The TD06 – 20G -10.5T is the perfect upgrade. This again, slightly increases turbo lag but has real potential for horsepower levels above 330hp at the wheels.

Turbo manifolds are slightly controversial. There is no doubt that there is a trend that replacing the stock manifold with after market Stainless Steel designs can improve power and throttle response. But conversely, many of these are cheap Chinese manufactured items and are prone to cracking continuously. Even some high priced brand name units suffer the same issues.

The factory cast manifold is extremely durable and for the majority of street / track vehicles, especially under high loads, is still the best design. It may not make the same peak horsepower, but it will last longer. There are some very good brand manifolds out there with great designs. But rather than being the first, it should be considered one of the last modifications you make to the vehicle.

Retune Factory ECU

The EVO vehicles have the benefit of being able to reflash the factory ECU. This enables the fuel, ignition, boost and many other features of the ECU to be altered to virtually any levels of modifications. Larger injectors can be tuned in, modifications in air flow, speed limiters, boost limiters are no longer an issue.

This has the advantage of retaining all of the factory ecu features, smooth idle, air conditioning and thermo fan control etc.

RPW specialises in the OpenEcu Tuning utilising a combination of EcuFlash and EvoScan. For more detailed information on this – check out our dedicated tuning section on the forum. We also have the ability to incorporate extra features like valet mode, flat shift changes (Depending upon models). We make one warning though – there are a lot of firms appearing these days claiming to be Evo Tuners using this software. Before getting your vehicle tuned, we recommend you find out how long and how many vehicles they have tuned.

Other brands which allows retuning of the ECU, are Ecutek and Versatune. This provides the exact same level of tuning as does the free ware EcuFlash, but has an additional expense of a license fee and locked ECU’s. The higher spec brand Ecutek has some advantages

But like everything, there are side effects. Tuning with these systems is done by datalogging and then flashing. Once the vehicles reach a certain level of modifications, the cost to retune can become very expensive. This is really only applicable once aggressive camshafts, combined with Stage 3 level of modifications are being used. In this case it may be time to move to a full after market ECU.

After market Plug and Play Replacement ECU

As outlined above, at some point you will need to consider a full replacement ecu. This is for serious modifiers only, but the good news is with the advanced units on the market, you can retain the majority of factory style driving. Smooth idles, average fuel economy but excellent power and torque. They all to a degree control fuel, ignition, boost and mivec (EVO 9). There are many brands on the market but the main ones we would recommend are

  • Haltech
  • Vipec
  • Links
  • Motec
  • Apexi Power FC

Whilst there are other brands on the market, they do not match the level of control that these systems can provide. The main benefit of these systems, other than not requiring any wiring changes, is that you can tune a vehicle in a very short time compared to reflashing / datalogging. We can tune a complete vehicle from scratch in approx 3 hours including boost curves. The tunes are also much more consistent and you can also add other advanced features like

  • Anti Lag / Rotational Idle
  • Advanced Boost Control incl boost by gear ratio
  • Duel mapping Systems
  •  E85 Fuel Flex system

Pricing can vary, but average pricing for supply and tuning will be around the $3000 – $3500 range.  For those chasing extreme modifications there is no choice, After market ECU’s are the best way to go.