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MPI general guide lines


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I feel as though there are many questions that have been answered through the years regarding the MPI conversion process but have been lost through changes in the site. Due to the format of this I will be posting this in multiple parts,

 

In the bigger picture, The MPI conversion is the process of converting from the ECI Throttle body injection setup which consists of a primary and secondary injector. Depending on the date of manufacture, your SQ will either be equipped with sequential injection or alternating injection.

 

Sequential injection will be utilized in 87.5 - 89 vehicles according to production date and will be seen with a Green and Black injector.

 

Alternating injection will be utilized in 87.5 and below with two injectors of the same color.

 

Both will do the job great when you leave the car stock. But If you're reading this you already know the flaws of TBI.

 

Now for the fun bits!

 

MPI conversion consists of 4 main principles,

 

- Intake manifold

 

- Fuel delivery

 

- Intercooler piping

 

- Engine management

 

 

Intake Manifolds are the easier part of the equation. The selection boils down to availability, which one can you find so to speak.

 

Here is a list I've complied through the years and I'll keep it simple. I will add pictures as I go along.

 

OEM Mitsubishi Magna - Most commonly found, and the most articulate of the Intake manifolds. The Manga Intake manifold is not a direct bolt-on. There have been many variations in the years as to how these are modified from a FWD application to a RWD application. More often than not you will find a Magna that has been already modified to fit. There are some that require an adapter plate and some that have been welded and milled to acommodate the larger rear coolant passage that the Australian G54 heads have. *be aware* there are Magna's that WILL NOT FIT due to longer intake runners that interfere with the brake booster and master cylinder.

 

Will fit

http://www.b2600turbo.com/images/IM008350.JPG

 

 

 

Fuel Injection Pro Hurricane - This manifold is no longer in production and is a custom made unit. This Manifold has been engineered to be a purpose built direct bolt-on MPI manifold for the G54. Although almost impossible to be had many people here have been running them with success both on the street and at the track.

 

http://www.angelfire.com/mech/edwardcase00/H-4S.jpg

 

EIP tuning Cannon - There are two versions of the Cannon. The "street" and the "race". The main difference between them is the Intake Plenum and runner length. The "race cannon" has a larger plenum with slightly shorter runners optimized with emphasis for High RPM and High volumes of air. The street version is not that much different, the plenum volume is slightly less and runner length is slightly longer with higher port velocity in mind for driving on the streets

 

http://i118.photobucket.com/albums/o113/solidboosttsi/eipcannon.jpg

 

Chad's MPI manifold -This is another purpose built MPI manifold that has been engineered to perform well through all conditions whether on the street or the track, the R&D put into the making of this has been pushed to the limits of the space constraints of the SQ engine bay.

 

http://webpages.charter.net/catsamuel/DCP01015.JPG

 

Gato Performance - I don't know too much about this manifold but from the years of talking to members equipped with this unit, there has been nothing but good numbers produced with this setup. Just like all the Purpose built Intake manifolds, the fit is clean and more inclined towards the Race applications.

 

http://www.ojperformance.com/Online%20Store/images/D/2.6%20Mitsubishi.jpg

 

Top End Performance MPI - Well.... It's a Stock TBI manifold modified with 4 injector bungs and a new fuel rail. The concept proved will in the late 90's and worked for it's intended purpose but the price was and still is outrageous for something with minimal amounts of effort put into it.

 

http://www.racetep.com/star4inj1.jpg

 

There are others that I have not mentioned such as

 

Maxboost's MPI manifold - There are variations of his manifolds and although I've never seen them in person, the craftsmanship and concepts are very innovative.

 

http://i1250.photobucket.com/albums/hh538/sqperformance/4sale/photo2_zps771a38ba.jpg

 

Which ever one you can get your hands on is going to dictate the direction for your build. If you have a choice of which to select, select according to your power expectations and your driving style.

 

 

 

 

I have personally owned a Magna, EIP Race Cannon, and am currently using one of Chad's MPI manifolds.

Edited by Bag-O-Chips
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Fuel delivery

 

Depending on the Manifold you are using it should have a fuel rail to compliment. Before you even consider purchasing a manifold do your best to get one as "complete" ans possible. Many of them I have seen do not include important parts such as fuel rails and fuel pressure regulators. On the Magna's the "other" option is a fuel rail from Trilogy Turbos, during their production run, some fit well and some have a slight offset that causes fitment issues. All of the other Manifolds have their respective fuel rails, The only concern you should have is making the feed line and return line work with the fuel rail.

 

http://www.shop.trilogyturbos.com/images/1195784963035-224518665.jpeg

 

Most people at this point will have upgraded their fuel pumps to something larger and along with that they've upgraded the lines to -6 (3/8") for street/ mild horse power to -8 (1/2") for high horsepower applications. Depending on your choice fuel such as Ethanol or Race fuel choose lines that will be able to resist their corrosive properties. The myth has been busted though, Both Technology and a few others have converted their cars to E85 with stock lines at one point with no difference in deterioration to their rubber lines. I personally use a Fuelab Prodigy fuel pump and Parker lines.

 

http://www.3sx.com/store/catalog/fuelab-fuelpump-diagram-stockpic-640.jpg

 

As long as the rubber lines are chemical resistant you should be safe. I my self recommend "parker push-lok" lines. I have been running E85 through -8 AN lines rated for 250psi working pressure and have had no signs of deterioration.

 

http://img.directindustry.com/pdf/repository_di/14175/hose-fittings-accessories-and-equipment-17456_26b.jpg

 

Filters - Filters are often overlooked when an MPI build is pieced together. You're making a big investment at this point. Because the SQ platform utilizes an external fuel pump, it makes things easy. Generally you'll want to have the cleanest fuel system possible. Inbetween the pump and rail usually consists of 2 filters in most race applications. A 100 micron from the pump and a 10 micron before the rail. This will ensure there are no contaminants in your fuel lines. You'll be surprised how a deteriorating rubber hose can wreak havok in a fuel injector. More common than not a misfire that you can't get rid of is because the fuel injector's screen filter is clogged or there is gunk keeping the pintle open and causing fuel to come out in globbules rather than the fine mist that it's supposed to.

 

http://www.ducatisportingclub.com/images/dsc/shazaam/DirtyInjector.jpg

 

I don't think I really need to elaborate on fuel injector selection, depending on your power expectations, choose a set that is slightly larger than what you need. It could save you in the long run. But I will eleborate on the type of injectors out there. Depending on the style of injector bungs you may be required to use Domestic style injectors as opposed to the more common Import style. They may look similar from a distance but their fit is worlds apart.

 

 

 

Take care of your fuel system.

Edited by Bag-O-Chips
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Intercoolers and Intercooler plumbing.

 

Why bigger is not always better. - At some point you will need to chill the air coming out of the mighty 12A...

 

Choosing and intercooler isn't entirely rocket science. There are Tube and Fin, and Bar and plate. The space is there, and the options are endless from Ebay specials to Race quality application specific units, be mindful with the type you choose. Some are direct bolt on units which emphasize on getting air to the radiator and some are universal "make it fit" type deals. Either way you go, don't forget, the Intercooler is a major part of the airflow equation that can be detrimental to your cars performance or the key to making big numbers. If your intake air temps are ice cold but your car overheats... you're not making any progress. Intercooler core selection play a major part in this.

 

http://www.perrinperformance.com/assets/2012/09/27/X-PSP-ENG-400_01_large.jpg

 

http://a3.ec-images.myspacecdn.com/images01/125/3e6af8c5d684f393f9f08ef26805dcf5/l.jpg

 

http://www.are.com.au/feat/techtalk/tti1001m.JPG

 

Keep in mind, an intercooler at it's peak efficiency will only cool boosted air as cold as the ambient temperature. You cannot expect your IAT's to be at 50* if the temperature is 80* on a summer day.

 

Plumbing the system is almost cut and dry, As a general tip going too big on piping diameter is not necessary. A 3" charge pipe is not only going to lose velocity, but will add a slightly noticeable amount of lag. More often than not, 2.5" is the happy median for volume and velocity on the SQ plaform. 2.125" - 2.25" is perfect for those with quick spooling turbos.

 

http://memimage.cardomain.com/ride_images/1/2796/1461/6988230016_large.jpg

 

Keep couplers to a minimum! If you can possibly minimize the areas for a boostleak please do so. In the bigger picture, you should really only have 4 places for couplers. Again, be mindful with how the engine moves. Unless you have solid engine mounts, the G54 be likes to wiggle even with New engine mounts, eventually this movement will cause flex in the couplers. The remedy for that are... flex or hump couplers.

 

http://www.mandrelbendingsolutions.com/catalog/blue%20cac%20cfl.jpg

 

 

I'll Add more later. Coffee is wearing off and I need ZzZzZz's

Edited by Bag-O-Chips
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Engine Management

 

Here's where things get complicated, The engine management unit or ECU is the heart and soul of the setup. Investing in the best you can afford is highly advised.

 

The majority have had success with Megasquirt, AEM, F.A.S.T., Autronic, Haltech, Electromotive, SDS, DSMlink, LinkECU and a few others I have failed to mention.

 

The options all the same in many instances. Making a wiring harness and obtaining sensors needed to make the conversion work are fairly easy to obtain. Some of the available EMS's have sensors built in to them. The other Main sensor that you should pay special attention to is the Knock sensor. The factory knock sensor can be made to work, but in some cases you will find it difficult to add a knock sensor. Do your best to utilize a knock sensor.

 

The 5 major sensors needed for any fuel injected engine to work are:

 

MAP/MAF - used for calculating load on the engine and and Airflow volume, Most of your fuel demands will be measured by these sensors depending on your setup.

 

http://www.holley.com/data/products/pictures/large538-13.jpg

http://www.iapdirect.com/images/T/30-2130-75_med.jpg

 

Crank/Cam position - During the conversion procces you will need a way to tell the ECU what position the crank or cam shaft is in. With out it, the ecu won't know where in the crank rotation to fire the injector or to fire the ignition coil. This is usually done through a magnetic pickup, Hall Effect sensor, or Optical sensor. A few examples are:

 

http://i1.ebayimg.com/05/i/001/17/05/fb55_35.JPG

http://www.msextra.com/doc/ms2extra/Ignition_Pixs/cas4-2b.jpg

http://starion.mrbdesign.com.au/images/Magnadist2.JPG

 

Oxygen sensor - This sensor is vital to the performance of your car. The purpose of the O2 sensor is to measure the amount of oxygen in the exhaust stream. In conjunction to the measurement of Oxygen, the ecu can determine how much fuel to add or remove in the map according to the values set in the ECU through this sensor's inputs. It is in your best interest it use a Wideband O2. Most if not all Stand alone EMS units will require an 0-5v input from a wideband for feedback. Not only that, but widebands are just more accurate.

 

http://www.horsepowerfreaks.com/images/products/aem/Wideband_Kits_AEM_30-4100.jpgplx-dm-5-wideband-o2-52mm-display-sm-afr-combo-black.jpg

http://sites.google.com/site/partsforspeedztx/ZTXZT2ZR2SB.jpg

 

 

Coolant temperature sensor - This sensor is another input that has a direct effect on fuel delivery. Warm up enrichment and fuel enrichment at optimum working temperature. With out it, the Ecu will not know if the Engine is stone cold or hotter than the breath of Hades.

 

http://www.auto-repair-help.com/images/articles/articles_0808/engine_coolant_temperature_sensor.jpg

 

Air Intake temperature sensor -This sensor functions the same as the Coolant temp sensor, The difference is it measures the temperature of air that is ingested by the engine. The ECU also uses this input to tailor the amount to fuel enriched whether to add or remove depending on what it has measured. In some cases, the IAT is also referenced by the ecu to compensate for Ignition timing advance in order to prevent pre-ignition and detonation or so commonly known as "knock"

 

http://www.omnitekcorp.com/images/tempsensors.gif

 

 

I hope this helps the many that are leaning in the direction towards MPI. I will add more information as I go along.

 

-Chips

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Very nice right up, and thank you for taking the time to write it. It's nice to have this in a collective place so that people thinking about switching know more what they are about to get into.

 

Shawn

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  • 1 month later...

What may help people as an add-on to this thread is if people post up what they are using in the same order that you presented the information. That way if anyone has any questions about a specific setup they know who to go to.

 

I'm using the FIP Hurricane manifold, Walbro 255 fuel pump w/ a Russell inline fuel filter right off the hard line (stock hard fuel lines to 3/8" stainless), 75# injectors, Sard adjustable FPR, *DM 4" thick IC w/2.25" in/out. Inlet pipe on the turbo is 3", charge piping is all 2.25". Engine management is via MS2 set up for ignition control, AEM wideband, locked dizzy w/MSD ignition control box, all tuned by Scott@Elutions Design Bureau (scott87star). Also running a full 3" exhaust. Not running any sort of knock control right now but I will be hooking one up shortly.

 

Great writeup!

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My set up is Chads Manifold, 1600cc injectors, E85, Fuelab Prodigy 140gph, or 530 lph for those used to walbro lingo., -8AN or 1/2" fuel lines - feed and return, SX fuel pressure regulator 3.5" Godspeed intercooler core with 2.5" plumbing, AEM EMS for a 1G eclipse, and a CAS for a 1G eclipse. Turbo inlet is 4" and the outlet is 2.5" , Throttle body is a 70mm Ford racing unit.

 

Glad to be of help!

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My set up is Chads Manifold, 1600cc injectors, E85, Fuelab Prodigy 140gph, or 530 lph for those used to walbro lingo., -8AN or 1/2" fuel lines - feed and return, SX fuel pressure regulator 3.5" Godspeed intercooler core with 2.5" plumbing, AEM EMS for a 1G eclipse, and a CAS for a 1G eclipse. Turbo inlet is 4" and the outlet is 2.5" , Throttle body is a 70mm Ford racing unit.

 

Glad to be of help!

 

price shiped to 97701?

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  • 9 months later...
  • 1 year later...
  • 4 weeks later...

where can I buy a chad's mpi?

 

Chad hasnt been on in a long time I think. The MPI manifold Chad modified is from an Australian car called the Magna. It will bolt onto our heads but needs a few modifications. Such as relocation the thermostat, relocating the throttle body and depending on which head you are using modification to the passage for the heater core flow. The starion has a smaller port on that versus the magna head which has a large port.

 

You can either weld in material to make it smaller or use two gaskets and a shim plate change it.

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