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Reverse frankenmotor turbo pre build thread AKA need help with full parts list


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So I've already got the EJ25, from my legacy, sourcing a 22 block won't be hard. Head gasket is tricky to me, where to modify it for oil lines ect. Also engine management, should I get a megasquirt?

 

http://www.ultimatesubaru.org/forum/topic/149590-anyone-built-a-reverse-frankenmotor/
I read through this thread which is quite good except there's some things I diassagree with

 

ej22t crank & rods -- same as the non turbo
ej25 (NA) block halves. The whole point of this is to use the ej22 short block
ej25 DOHC heads ('96 with hydro adjusters) -- should be able to just use my heads
newer EJ25 flat top pistons -- Aren't my current pistons/ the 22's pistons sufficient?
ej20g intake manifold with 440cc injectors -- One of the 2 manifold I have will be good, no?

vf8 turbo (ej20g)
ej22t exhaust (until I put the downpipe in)
ej22t fuel pump
2002 WRX top mount IC
ej22t bypass valve (I replaced with the TurboXS one)
ej22t ECU & wiring harness. original ej25 harness/ECU is gone, and the
ej22t ECU sits in it's place, and is all wired in, and I can check code like normal (ej22t way)
 -- I shouldn't have to use a 22 turbo block, can just use a normal block, almost the exact same. So the wiring harness mesh is moot then, right?

 

Would absolutely love to do this build, but need to have all the parts before I do the biuld, and have as much of it pre assembled as I can as it's my dd. 

 

Thanks - H

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Wire harness has to match the electrics on the intake manifold.

If you want to do a turbo setup you'll need a turbo ECU and body side harness, and turbo manifold harness to match. Use the intake manifold that matches the ECU and wire harness. Use heads that match the manifold.

 

You're better off to use a turbo block because its a stronger design (look up the difference between open and closed deck), but the 2.2 blocks can handle some power if properly built and managed. You can run a stock 2.2 bottom end with a turbo but the longevity will be questionable.

The EJ22T crank and rods are forged, which makes them stronger and more suited to turbo use. And the 22T pistons have a deeper crown which gives a lower compression ratio.

 

The rest is just gathering the necessary parts for the turbo system: headers, up-pipe, down-pipe, intake tubing, intercooler, etc.

 

The wiring and tuning will be easiest if you use a turbo harness and ECU. This will require some wiring to be done in the car to integrate with the dash harness, or will require an entire dash harness swap. Megasquirt is a viable option if you're up for setting up ALL of the wiring going to the control unit and figuring out the tune parameters. Megasquirt sounds cool but it is a TON of work and no guarantees that it actually will work.

 

You can use an ECU that's compatible with RomRaider or Evoscan and do the tuning yourself, or you can use a Cobb Accessport for tuning and Cobb even has pre-made maps for many setups.

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Cobb has nothing for pre 02 ecus, and evoscan is simply a logging tool. As mentioned in the OP ej22e and ej22t rods and cranks are identical, this has been proven true for over 15 years. The only stronger oem rods are those from the ej257 or jdm ej207, but it's not worth splitting the block to replace them. The hybrid you're building has been proven tough many times over. You'll need to use cometic or stock ej22t head gaskets for the coolant ports to match the head, you can simply order them suited for the ej22t and be done with that aspect.

 

You will need bigger injectors, and a way to tune them, if you intend on running more than 5-6psi. Usdm 04-06 yellow top STi injectors swap right into ej25d rails and flow 525cc as opposed to the ej25d red top flowing 285cc. If you or someone you know is familiar with building and tuning with MS by all means go for it, it's not something I would attempt myself. Any good piggyback ecu will do what you need for this type build. Just do your research carefully before spending money on one. Some don't play as well as others with subaru electronics.

 

Don't jump into an ecu swap, especially not the 02+ versions. There are several electrical differences that will make them hard to get running correctly, if it's been documented on how to run a phase 1 dohc motor on a wrx ecu please link me to it. I couldn't find it 2 years ago, and still can't to this day.

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Cobb has nothing for pre 02 ecus, and evoscan is simply a logging tool. As mentioned in the OP ej22e and ej22t rods and cranks are identical, this has been proven true for over 15 years. The only stronger oem rods are those from the ej257 or jdm ej207, but it's not worth splitting the block to replace them. The hybrid you're building has been proven tough many times over. You'll need to use cometic or stock ej22t head gaskets for the coolant ports to match the head, you can simply order them suited for the ej22t and be done with that aspect.

 

You will need bigger injectors, and a way to tune them, if you intend on running more than 5-6psi. Usdm 04-06 yellow top STi injectors swap right into ej25d rails and flow 525cc as opposed to the ej25d red top flowing 285cc. If you or someone you know is familiar with building and tuning with MS by all means go for it, it's not something I would attempt myself. Any good piggyback ecu will do what you need for this type build. Just do your research carefully before spending money on one. Some don't play as well as others with subaru electronics.

 

Don't jump into an ecu swap, especially not the 02+ versions. There are several electrical differences that will make them hard to get running correctly, if it's been documented on how to run a phase 1 dohc motor on a wrx ecu please link me to it. I couldn't find it 2 years ago, and still can't to this day.

The ecm/tuning is what's got me stuck. I can solder and make circuit all nice but reading and understanding wiring diagrams is completely lost on me. And MS I don't really know anyone good with it, was just what I was planning on using for my miata (rally miata  :grin:  :grin: ) and has the reputation of a basic tuning platform. I have a subaru specialist I know in town, but no idea how good he'd be for this.

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If there are any tuners in your area just go speak with them. See what types of systems they are familiar with, and what they would recommend. I know many people have had good luck with the Greddy eManage Blue on the phase 1 cars, there is a guy on rs25.com who was making around 350hp on an ej22e/25d hybrid self tuned on the eManage.

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