a few questions

Heads, valves, pistons, rods, crankshaft, etc...

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R1Linc
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a few questions

Post by R1Linc »

I am a former DSM guy. I sold off all my old junk and am looking for a new project. I like the legacy because up untill 2 weeks ago i didn't know they were built with a turbo. Meaning not to many people have them. They seem light in comparison to dsm's and they are AWD.

What are the limits of the stock engine internals?

I understand the heads are the week point in these cars. What are alternitives to the SOHC heads that came stock? Impreza heads??
IronMonkeyL255
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Post by IronMonkeyL255 »

Looking at the Stickies in this very section would answer most of your questions, but I'll give a synopsis here:

The stock engine internals are stupid strong. Subaru over-engineered our blocks with a strong, closed-deck casting, forged crank, moly-coated cast pistons, piston oil squirters, and some other stuff I'm forgetting. In many cases, upgrading to current WRX parts is actually a downgrade, because the stock parts are so beefy.

You seem to be able to use just about any heads from another EJ-series motor. Many people here are running EJ20G heads from overseas WRXes or Phase II EJ25 SOHC heads. The EJ25 heads have been tested to greatly outflow the stock heads, but you have to get creative in coolant and oil line routing to get them to work.

Hopefully this will help you some.

I plan on dropping an entire STI drivetrain into my 1g Legacy, so I see where you're going with the sleeper idea. Everyone knows DSMs can be crazy fast, but an early 90's Subaru?

I still recommend reading the stickies at the top of this forum, as well as the technical writeups that can be found by going to the LegacyCentral main page and following the 'Library' link.


If anyone notices I made an error, feel free to correct me. That's just off the top of my head, and it's too early for me to think properly.
Last edited by IronMonkeyL255 on Thu Jun 08, 2006 4:08 pm, edited 1 time in total.
Disclaimer: If anything I post is inaccurate, please correct me. I do not wish to add to the misinformation floating around on the internet.

That being said, everything I post is accurate to the best of my knowledge.

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All_talk
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Post by All_talk »

That covers the basics, like IronMonkey said do some pokin around here and you'll find lots of great info.

And just cause is such a beautiful piece here's a pic of the crank and rods (rods are forged too BTW).

Porn for gearheads...

Image

Gary
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Post by Matt Monson »

I've never heard of a semi forged piston before??? For the record, the Ej22T pistons are a moly coated cast piston...

Also, the liability of using the SOHC Ej25 heads is that the up-pipe doesn't clear the rear corner of the head. It can be remedied with some spacers and some body english, but the problem exists. Also, some believe that there are issues with how the coolant passages line up.

The easiest and most available head swap is '96-99 DOHC Ej25 heads. Look for Napphappy's thread on the subject for a basic ho-w-to to make that build happen. It's pretty easy to do, and those heads do outflow modern WRX heads.

Avoid modern '00+ WRX heads like the plague. There are issue with the cam gears and triggers that you need to get around. It's too much headache when the DOHC Ej25 heads are cheaper and easier to put into the car...
1974 Porsche 914 Cam Am Limted Edition AKA the Bumble Bee
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IronMonkeyL255
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Post by IronMonkeyL255 »

Fixed my original post.

I heard someone refer to them as that, and for some reason it stuck.

Point is, they're strong pieces.
Disclaimer: If anything I post is inaccurate, please correct me. I do not wish to add to the misinformation floating around on the internet.

That being said, everything I post is accurate to the best of my knowledge.

Rio Red '91 Legacy SS
vrg3
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Post by vrg3 »

Welcome.

Just so you won't be disappointed, I should point out that a Legacy Turbo is a good deal heavier than an AWD DSM turbo from the same era, and makes a good deal less power from the factory.
"Just reading vrg3's convoluted, information-packed posts made me feel better all over again." -- subyluvr2212
IronMonkeyL255
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Post by IronMonkeyL255 »

~3200 lbs for an auto and ~3100 lbs for a manual, IIRC.
Disclaimer: If anything I post is inaccurate, please correct me. I do not wish to add to the misinformation floating around on the internet.

That being said, everything I post is accurate to the best of my knowledge.

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Post by All_talk »

To put a finer point on it... the EJ22T uses hyperkinetic cast pistons, they're the best you can do without going forged. Production cars rarely use forged piston due to there higher thermal expansion rate and need for greater piston to bore clearance, makes for a lot of piston noise and greater oil consumption.

Gary
No matter how broke I am... I always seem to find two cents.
IronMonkeyL255
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Post by IronMonkeyL255 »

That's probably what I was thinking of.

I have seen someone refer to that as semi-forged, and the term stuck.
Disclaimer: If anything I post is inaccurate, please correct me. I do not wish to add to the misinformation floating around on the internet.

That being said, everything I post is accurate to the best of my knowledge.

Rio Red '91 Legacy SS
sammydafish
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Post by sammydafish »

All_talk wrote:To put a finer point on it... the EJ22T uses hyperkinetic cast pistons, they're the best you can do without going forged. Production cars rarely use forged piston due to there higher thermal expansion rate and need for greater piston to bore clearance, makes for a lot of piston noise and greater oil consumption.

Gary
you mean hypereutectic
- Junior
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95L Wagon on T3/T4 boost :)
www.trdsupra.com [b][url=http://trdsupra.com/library/forsale/]Cheap parts![/url][/b][quote="Imprezive"]alright, I give up, I'm going to NASIOC...[/quote]
555BCTurbo
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Post by 555BCTurbo »

IronMonkeyL255 wrote:~3200 lbs for an auto and ~3100 lbs for a manual, IIRC.

My manual SS weighs 3050 full weight with a sub in the trunk :D
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Post by free5ty1e »

What kinda diet did you put her on?
-Chris
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91SS 5MT rebuilt engine waiting for a shell
93TW 4EAT, Forester lift, 3" TBE, 11psi, 200k mi
94SS 5MT4.11+rLSD 311k km: RobTune550,TD05-16g @ 18psi,FMIC,3"TBE,Forester lift
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Post by All_talk »

sammydafish wrote:
you mean hypereutectic
Yes, I did, thanks sammy. :P (I looked it up this time)

For those who want to know what it means...

http://en.wikipedia.org/wiki/Hypereutectic_piston

Gary
No matter how broke I am... I always seem to find two cents.
IronMonkeyL255
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Post by IronMonkeyL255 »

Kewl.

Wonder if we've scared him off yet... :lol:
Disclaimer: If anything I post is inaccurate, please correct me. I do not wish to add to the misinformation floating around on the internet.

That being said, everything I post is accurate to the best of my knowledge.

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Post by 206er »

how much do dsm's weigh?
1994 Touring Wagon: ruby mica, 5mt swapped
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Post by All_talk »

IronMonkeyL255 wrote:Kewl.

Wonder if we've scared him off yet... :lol:
Ahh, I doubt it, but if we did hes not up to the T-Leg challenge. :P

Coming from the DSM world wait tell he finds out that about the only aftermarket support for Subarus is for the current WRX and those parts are almost never a direct fit... modding the T-Leg is not a bolt on affair, but then thats the real fun of it any way. :D

Gary
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sammydafish
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Post by sammydafish »

umm.... DSMs and SS Legacys are about the exact same weight.

1993 SS: 3100lbs
1993 GSX: 3093lbs

the DSM is actualy lighter.
- Junior
90L Wagon EJ22E on Toyota CT-26 boost -- Crushed!
95L Wagon on T3/T4 boost :)
www.trdsupra.com [b][url=http://trdsupra.com/library/forsale/]Cheap parts![/url][/b][quote="Imprezive"]alright, I give up, I'm going to NASIOC...[/quote]
IronMonkeyL255
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Post by IronMonkeyL255 »

All_talk wrote:modding the T-Leg is not a bolt on affair, but then thats the real fun of it any way. :D

Gary
Ghetto Garage FTW!!11!

I got a WRX hoodscoop to direct air toward my soon-to-have WRX i/c... :lol:
Disclaimer: If anything I post is inaccurate, please correct me. I do not wish to add to the misinformation floating around on the internet.

That being said, everything I post is accurate to the best of my knowledge.

Rio Red '91 Legacy SS
Matt Monson
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Post by Matt Monson »

sammydafish wrote:
All_talk wrote:To put a finer point on it... the EJ22T uses hyperkinetic cast pistons, they're the best you can do without going forged. Production cars rarely use forged piston due to there higher thermal expansion rate and need for greater piston to bore clearance, makes for a lot of piston noise and greater oil consumption.

Gary
you mean hypereutectic
All Talk,
Please site your source??? modern STi pistons are hypereutectic, but this is the first I have ever heard of this for Ej22T pistons. I am not calling you a liar, but without some technical information to back it up, I never ever take at face value something I read here or anywhere else. It goes back to my old signature...

I don't care who's right or wrong, I just want to know the right answer. The eternal quest for tehcnical truth... :-D
1974 Porsche 914 Cam Am Limted Edition AKA the Bumble Bee
1973 Porsche 914 2.0 l -Suby swap pending
1968 Porsche 911t survivor 47k original miles
2000 2.5RS daily driver.
1999 2.5RS w/ 50+ extra whp
Suby Hai!
Brat4by4
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Post by Brat4by4 »

All_talk wrote:Coming from the DSM world wait tell he finds out that about the only aftermarket support for Subarus is for the current WRX and those parts are almost never a direct fit... modding the T-Leg is not a bolt on affair, but then thats the real fun of it any way. :D
What have you been smoking? :smt017 There are many more bolt on parts than those that need modding, especially since its quite common to see GC parts for sale from vendors. Body parts don't count - ex: no one expects to be able to put Accord body kits onto a Civic... :smt048
1993 WMP BC6 5MT EJ22T 9psi 3.9:1 213k 205/55R16

62.6 m/s @ 0.66 bar. Gotta love boost. :)
All_talk
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Post by All_talk »

Matt Monson wrote:
All Talk,
Please site your source??? modern STi pistons are hypereutectic, but this is the first I have ever heard of this for Ej22T pistons. I am not calling you a liar, but without some technical information to back it up, I never ever take at face value something I read here or anywhere else. It goes back to my old signature...

I don't care who's right or wrong, I just want to know the right answer. The eternal quest for tehcnical truth... :-D
I have no source, just what I heard and believed to be true... so untell I (or someone else) shows otherwise I am a liar, and they are just eutectic cast. :D

Brat, Yes a lot of the newer Subie stuff will work, some direct, some if you swap some other parts with it, but a lot of the stuff we really want (like upgrade turbos, ICs, intakes & exhausts) only fit with a bit of ingenuity. I guess the point is very few vendors are marketing directly to the gen1 Legacys... there just aren't enough of us around (and most of us are poor). But remember... if it was easy everyone would do it. :) (FYI, I dont smoke, but that dont mean I think straight either)

Stupid Liar
Gary
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napphappy
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Post by napphappy »

According to the SAE Paper. The crank and rods are forged and the pistons cast. It does not mention any silicon content in the pistons.

A helpful discription of what Hypereutectic means.
http://en.wikipedia.org/wiki/Hypereutectic_piston
1997 White BG Ltd 5MT, EJ22T with Wiescos, EJ20R Heads, Two large dents R.I.P
1995 Impreza EJ22T DOHC Hydra EMS, 20g, EWG, 3in APS TBE, AWIC
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