How to turbo a hybrid motor?

[nikolaus.conrad]

I'm thinking about doing a hybrid motor build (2.2 block with 2.5 heads) in the future and I'm wondering what kind of turbo to use? Would a turbo from a 1990 to 1994 Legacy turbo work? Thank you!

Edit: I apologize if this has been brought up before, I couldn't find a post on it.

[Garrison]

The turbo you're suggesting would work fine, but it would run a lot like a jetta tdi; that is to say great for getting from 1500-3500 rpm boost and great from stoplights. That's about it. By going with that turbo you would be selling your proposed setup short. I would suggest nothing less than a td04 and preferably something a bit larger.

[anothernord]

That turbo would be WAY too small. It wouldn't hardly be able to push past 10 psi, and it would taper down horribly.

At minimum, get a TD04 from a WRX. Even that will limit you quite a bit, look for a VF39, TD05h, or something in the 16g range, and you'll be much happier.

[lord flashheart]

i think this is my area of expertise.
hybrid long block is a inexpensive way to go. the ej22 bottom end is strong and the EJ25D heads flow numbers rival that of a STi.
sooooooo im gonna give u a short run down.
so if your car has an EJ22 in it its slightly harder.
i personally would recommend a car that has a 2.5 in it already. why?
1 beacuse the Ej22 manifold and the EJ25 heads are not compatable. so you wouldnt have to swap it.
2 EJ22s are easyer to come by becasue the damn things never break.
3 the Ej25 ecu revs to like 6600 rpms before fuel cut. the EJ22 hard fuel cut is 6000. (soft fuel cut feels like 5800 to me)
4 you dont have to have timing covers and crap like that.

also, there are quite a few parts i would recomend having to help with fitment.
legacy turbo take-off parts are going to be your friend.

- Idle air control valve (the 90-94 legacy turbo one has an elbow on it that makes fitment easier.
- unless you have engine management in mind, use a VF10 or VF11 because they have a plasitc elbow on it which makes fitment much simpler.
and your injectors will only handle 7-9lbs. and both those turbos are good till over 12 psi.
- AFR guage.
- any OEM (JDM or USDM) exhaust manifold except of of the EJ255/EJ255 (because they require a different oil pan.
- oil return and oil feed lines from any DOHC turbo car, EXCEPT the twin turbo engine.
the EJ25D heads have the oil galley for the turbo feed/return. not mod required.
- Forester XT intercooler.

also be prepaired to cut your cross-member. or swap a legacy turbo cross-member in because the turbo cars have a notch for the up pipe.

i gotta run but if you have questions about it post in my build thread. im more than happy to answer questions on it.

[anothernord]

Don't forget a turbo water pump if you're using an OEM turbo manifold. Aftermarket ones will clear the N/A one though.

It's not that hard to fit a 2.25" 90 degree elbow on the turbo if you want to use something that doesn't have the elbow cast in.

Flashheart pretty much covered it though.

[lord flashheart]

doh.
forgot about the waterpump.
good call anothernord!

[nikolaus.conrad]

Thank you for replies!

Garrison- I really don't know turbo size number or letters (TD04) what does this mean? I'm just stepping into the world of forced induction engines so I have a lot to learn. I know the basics, so I'm not a complete noob. yay lol

Lord Flashheart- I have a dead 2.5 DOHC engine I'm tearing apart, so I have both heads and intake manifold. I'm just keeping an eye out for a low mileage 2.2 if I ever come across one. I'm sure I'll be Emailing you in the future

Anothernord- I'll keep an eye out for that too, I imagine all the Impreza forums would be selling those? also, what would be the difference between a TD04 and TD05 turbo? I can find more for the TD05 but if the TD04 works better then I'll stick with that.

Again Thank you! I've read over Lord's and Anothernord's builds quite a few times, so if I ever have any questions I'll be sure to ask!

[anothernord]

TD04 is just the "part number" of the turbo. It doesn't really mean anything as far is denoting it's size or anything. Anyway, it's good for 390 CFM at 14.7 ish PSI. The TD05H-16G, which is a particular turbo from the older JDM WRX's that a lot of people like, flows 500-something CFM.

Bottom line: The TD04 will give you a fun torque kick from 3-4K, but then it dies off quicker than a fly. The TD05H-16G will carry power all the way to redline.

Other turbos to look for would be the VF39, VF22, VF30/34, or a small 16G-sized turbo.


My recommendation? Since you're new to this all, just grab a cheap VF11 from a turbo legacy to tune/mess with, then after you figure out how to get everything running well, upgrade.

[Garrison]

I like this site
http://www.ztechz.net/id4.html

[nikolaus.conrad]

Awesome! I'll be reading that page for the next few days.

A few questions I have at this point:
1. How much boost should you run on the 2.2 with 2.5 heads hybrid? (Less than 5psi for DD?)
2. How do you adjust the amount of boost you want?
3. How would you go about to tune the setup?
4. Would I need a piggyback to run a VF11 turbo setup?

I know that these questions depend on what kind of turbo I would be running, since you recommend the VF11, then that's what I'll start with and see how it goes from there.

[GTDrifter]

added to favorites...thanks flashheart

[Garrison]

Awesome! I'll be reading that page for the next few days.

A few questions I have at this point:
1. How much boost should you run on the 2.2 with 2.5 heads hybrid? (Less than 5psi for DD?)
2. How do you adjust the amount of boost you want?
3. How would you go about to tune the setup?
4. Would I need a piggyback to run a VF11 turbo setup?

I know that these questions depend on what kind of turbo I would be running, since you recommend the VF11, then that's what I'll start with and see how it goes from there.

1) Hybrids have the beauty of lower compression without much displacement loss (I think they come in at ~2.3L) which means you aren't limited to 5psi. 12-15psi with Sti headgaskets *maybe*
2) Different ways: wastegates, boost controller (manual or electronic)
3)AEM F/IC 30-1910 or Greddy Emanage (Blue or Ultimate) (You need something to help retard timing to eliminte knock in higher psi applications); unnecessary below ~8psi.
4) No

[lord flashheart]

word on the street is there is a dude in colorado, who has this hybrid and he runs something like 19lbs on it and has had it up to 23lbs or some craziness like that. the bone stock EJ22E should handle 11 or so lbs. i plan to make a shoot for 300WHP with mine.
see, the EJ22 phase 2 uses the same crank and rods as the EJ205. but it has SOHC, and the combustion chamber is something like 35ccs or so,
if you put EJ25D heads on it which can flow as good as STi heads (with unshrouding), have a clover combustion chamber (which gives you a good 'quench' area) of like 52cc it takes your compression ratio to like 8.5 to 1.
its basically a EJ20 thats been bored out .2 liters and has STi heads on it.

[anothernord]

Yes, I was actually mentioning the guy in CO who had this setup (he's not the only one) but he tried to blow it up by just cranking the boost to 23 PSI on the track, and it still didn't blow. That doesn't mean it was untuned, but it shows that it didn't detonate at that level of boost. Maybe he just got lucky. Either way, I wouldn't run that much boost anyway.

[nikolaus.conrad]

Jesus! I think I read about that, pretty amazing to hear such a thing. I wouldn't run that much all the time, probably hardly at all or never. I'm just looking for a bit more punch from a stoplight is all, maybe 7psi or less for a DD. Like I said, with just starting out, I want to learn more before I jump into something ridiculous like that :smt016 It's pretty cool that these parts that run our ordinary cars everyday can be bolted together to make a beast motor like that. I understand that tuning is everything, that is what is making me so nervous about this kind of build because I'm worried I'm not going to tune everything correctly.

I have heads from a 1997 Legacy GT, so they are mechanical. I'm looking for a later year 2.2 like a 1997 to 1999 because Subaru reworked the engine to lower friction in the cylinders and the have slightly more power than the older ones. Would these be a phase II?

Edit: I thought the EJ22E was the Australian domestic market EJ22? Correct me if I am wrong.

Double Edit: sorry, double post.

[lord flashheart]

if you are only going to run 7 lbs, i would say just use a stock EJ22. cuz like i said if you change the head, the compression goes down so your boost is less effective, if that makes sense.
7psi on a stock EJ22 is roughly the same as 10 or so psi on the low compression version.

[nikolaus.conrad]

It does make sense, I understand, because the 2.5 has a larger combustion chamber as you stated above. I'll probably still go with the hybrid build if I ever want a larger turbo later on

[redlegacygt]

Im actually going this hybrid build route as well. I have an line on a 2.2 bottom end and have ej25 heads sitting at the house. I also have 22t internals that i may throw in as well. Also have a tdo4 and wrx intercooler but will prob sell that for a forester xt intercooler. Hopefully i can pick up a greddy emanage blue and should be ready to go.

[nikolaus.conrad]

Cool beans! I was looking up prices for the Greddy Emanage and since I'm just starting out, I'll stick with my basic setup for now lol. I already have an intercooler from a previous (not successful) project. It's a slanty intercooler from a Japanese WRX. I've test fit it on the Outback and everything clears. I'm just not sure if it'll fit when the turbo is installed.

Hey, you live in Danville! I just passed through a few weeks ago to go to Knobles!

[lord flashheart]

dont use the EJ22T pistons tho, it will drop your compression ratio pretty low. but cool man, im glad to see people opening there eyes about this engine.


the Slanty will work. thats the one i have on my car. the best one for your car is the 06-07 WRX intercooler with the Y pipe kit.

[nikolaus.conrad]

You're starting a trend, Lord Flashheart

The 06-07 WRX intercooler is the thinner one correct? Also, my slanty has no BOV, is there another place I can add one?

[redlegacygt]

Cool beans! I was looking up prices for the Greddy Emanage and since I'm just starting out, I'll stick with my basic setup for now lol. I already have an intercooler from a previous (not successful) project. It's a slanty intercooler from a Japanese WRX. I've test fit it on the Outback and everything clears. I'm just not sure if it'll fit when the turbo is installed.

Hey, you live in Danville! I just passed through a few weeks ago to go to Knobles!

haha well thats cool. its a good thing you went when you did, its totally under water right now.. some of the worst flooding in years...

[lord flashheart]

people dont know me in real life. ima looooser.

yes, its almost the same intercooler as the FXT one, but the WRX one is slanted on the blowoff valve mounting area so it clears the throttle cables.
JDM wrx Version 1-2 and the Legacy turbo use a "in-line blow off valve, there should be a port on the elbow of your intercooler. thats where it attaches..
if you cant find one when you decide you need one, i have like 4 of them so PM me and ill sell ya one cheap.

[nikolaus.conrad]

Cool beans! I was looking up prices for the Greddy Emanage and since I'm just starting out, I'll stick with my basic setup for now lol. I already have an intercooler from a previous (not successful) project. It's a slanty intercooler from a Japanese WRX. I've test fit it on the Outback and everything clears. I'm just not sure if it'll fit when the turbo is installed.

Hey, you live in Danville! I just passed through a few weeks ago to go to Knobles!

haha well thats cool. its a good thing you went when you did, its totally under water right now.. some of the worst flooding in years...

I believe it, northern Pennsylvania got slammed with rain from Lee. Williamsport got 4 inches in a day.

[nikolaus.conrad]

people dont know me in real life. ima looooser.

yes, its almost the same intercooler as the FXT one, but the WRX one is slanted on the blowoff valve mounting area so it clears the throttle cables.
JDM wrx Version 1-2 and the Legacy turbo use a "in-line blow off valve, there should be a port on the elbow of your intercooler. thats where it attaches..
if you cant find one when you decide you need one, i have like 4 of them so PM me and ill sell ya one cheap.

Hahahaaa nooo :smt016

The guy I bought it from used it on his 2.5RS which he had swapped with an early JDM STi engine (1994 or 1995 I think). There is a 90 degree elbow on the piping right next to the turbo which I think is what you are talking about.

[TGX4776]

this is bad for me to be reading at the moment. trying to save money

[nikolaus.conrad]

LegacyCentral.net BBS forum is for all the 1st gen Leggy owners, people parting out their cars usually sell turbo bits for dirt cheap. I'm probably not helping you try to save money :smt016 lol

It kind of makes me miss my 1st gen Legacy, even though it was front drive with an autotragic

[nikolaus.conrad]

With this hybrid setup, what type of head gaskets would you use? I just thought of this a few days ago.

[Garrison]

Sti head gaskets.

Btw, this should put an end to all the debate of the ej25d being weaksauce.
http://www.rs25.com/forums/f7/t39629-boosted-ej25d.html

[mycargoesvroom]

Sti head gaskets.

Btw, this should put an end to all the debate of the ej25d being weaksauce.
http://www.rs25.com/forums/f7/t39629-boosted-ej25d.html

Skully is a beast.