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#1 |
Scooby Guru
Member#: 58779
Join Date: Apr 2004
Chapter/Region:
MAIC
Location: The Skook
Vehicle:2015 Honda Fitbox 15 Legacy kid hauler |
![]() Maybe I'm onto something. Maybe I'm stupid. But i was looking over a chart of specs of all the subaru engines built, 91 and up. I was looking at the different sizes of things and their compression. I also remember somebody comparing these cars to lego blocks. So i was thinking maybe I(or someone else) could build a high compression motor with stock parts or aftermarket parts made to fit the stock vehicles. I personally think that it would be cool to build a powerful NA motor over a period of time, and someday swap it into my Prezza. Or like I said, maybe I'm just stupid. But hey, at least I dod something constructive during study hall.
the list of parts and reasons are as follows: My stock engine is the NA EJ22, just for reference. If I would ever do this, it would be a second engine, but i want to keep to the 2.2 block. Because of the above, the first part is: MY91-94 EJ22T block. its built sturdier than the NA, or so im told. The following is a choice of the 2, but i dunno which would be better: MY98 EJ25 DOHC cylinder head (cuz its dohc) OR ![]() MY00-04 EJ25 SOHC cylinder head (boasts higher compression) I also dont know about the following. I dont know if they will fit(prob not), of it they'll help me with power or anything but...: MY98-04 connecting rods and crankshaft. If they dont work, id go with the EJ22 or EJ22T rods and shaft. MY97-98 EJ22 pistons (higher compression, and they'll fit) finally... MY97-98 SOHC EJ22 head gasket. (higher compression than the dohc gasket) I'd like to stick to better than OEM parts on stuff, including the other stuff, such as clevite bearings and arp bolts/studs my questions are: Will it all fit? What kind of compression would be expected? What about engine magement? Sohc head or dohc head? Would it start? Any other suggestions? One more thing... am I freakin nuts? ![]() -shaun Last edited by t3hWIT; 09-21-2006 at 01:06 PM. |
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#2 |
Scooby Guru
Member#: 6486
Join Date: May 2001
Chapter/Region:
MWSOC
Location: S.E. wisconsin
Vehicle:00 Impreza 2.5 RS Blue Ridge Pearl |
![]() I think the best thing you could do is get all the stats of all the parts you are considering using and take it to an engine builder. Have a little chat with them and see what they think.
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#3 | |
Scooby Guru
Member#: 58779
Join Date: Apr 2004
Chapter/Region:
MAIC
Location: The Skook
Vehicle:2015 Honda Fitbox 15 Legacy kid hauler |
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![]() not being an ass here but if i was gonna spend that much money, id just turbo the thing. theres a twin turbo kit out there. and this HC thing is junkyard parts. ![]() |
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#4 | |
Scooby Specialist
Member#: 33863
Join Date: Mar 2003
Chapter/Region:
TXIC
Location: DFW
Vehicle:2001 rs2.5 silver/champaign |
![]() Quote:
EXACTLY!!!! i have the $ to do an NA build with 11.5:1 compression pistons, cams, intake and more but i decided that by the time I finish the build with costs and tuning, i an 3/4s of the way to a wrecked useable driveline STI swap. so why at that point would i want to do a na build when the stock sTi would smoke it? sure 220-240 whp sounds cool in NA, but then your maxed out. stock STi is 240-250 range and with a small tune and nothing more, you can make an extra 30-40hp crank or 15-20 wheel power before you touch it it other than tuning. always passed na then. my costs estimated for a decent NA build is $4500 for the engine assembly done. a wrecked STI is $5k-$6500 depending on damage and milage. do the math. you do an NA build because you want to be different and have extra $. |
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#5 | |
Scooby Specialist
Member#: 220816
Join Date: Aug 2009
Location: Pittsburgh PA
Vehicle:2018 Exotruck |
![]() Quote:
I like many others suck at saving money, so saving 5k for a 1 in a 1000 insurance right off is out of reach. I did however have a couple half good engines laying around and a part number for a cometic head gasket set. I now have the torque i need to save 20 minutes a day commuting by lane jumping before the tunnel. And can still afford my raceland coilovers. |
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#6 |
Scooby Guru
Member#: 58779
Join Date: Apr 2004
Chapter/Region:
MAIC
Location: The Skook
Vehicle:2015 Honda Fitbox 15 Legacy kid hauler |
![]() and i live in central Pa, aka Penntucky. the closest thing to an engine builder we have is the neighborhood mechanic, or some guy at AAP who'll gather the parts together. The biggest thing in tuning around here is slapping a big ol aluminum wing, stick on hood scoops, chrome exhaust tips, and APC spinner wheel covers. I'm interested in performance and teaching these tuner wannabes a lesson in real cars. But since I'm one of the few and proud, i dont have access to this stuff. just junkyards. ugh... i hate this region...
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#7 | |
Scooby Newbie
Member#: 477188
Join Date: Nov 2017
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#8 |
Scooby Guru
Member#: 6486
Join Date: May 2001
Chapter/Region:
MWSOC
Location: S.E. wisconsin
Vehicle:00 Impreza 2.5 RS Blue Ridge Pearl |
![]() Maybe you misunderstood, If you get the copies of the service manuals you can have a nice reference for all the parts you are considering using. I did'nt suggest that you go get all the parts and mickey mouse around with them.
Have at it and good luck. Like to see what you come up with. |
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#9 | |
Street Racing Instructor
Moderator Member#: 110
Join Date: Jul 1999
Location: 1997 OBS, 1996 SVX, 1988 RX
Vehicle:1989 1989 XT6 |
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#10 | |
Scooby Specialist
Member#: 2181
Join Date: Aug 2000
Chapter/Region:
SCIC
Location: So Cal
Vehicle:2003 Forester XS |
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#11 |
Scooby Specialist
Member#: 42188
Join Date: Aug 2003
Chapter/Region:
AKIC
Vehicle:2002 |
![]() get as close to 13:1 compression as possible..
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#12 | |
Scooby Newbie
Member#: 56520
Join Date: Mar 2004
Vehicle:2002 WRX White |
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If you are going to build a real n/a beast then you should shoot for 14:1 - 16:1 |
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#13 | |
Scooby Newbie
Member#: 26201
Join Date: Oct 2002
Chapter/Region:
South East
Location: Somerset, KY
Vehicle:2015 Impreza Premium Charcoal |
![]() Quote:
And just WHAT kind of fuel would you run in a 16:1 motor, as is sure wouldn't be pump gas ![]() |
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#14 | |
Scooby Newbie
Member#: 80670
Join Date: Jan 2005
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#15 | |
Scooby Guru
Member#: 832
Join Date: Jan 2000
Chapter/Region:
RMIC
Location: Teh Ghetto Garage, CO
Vehicle:99 2.5RS, '85 911 '73 914 and 2012 BRZ |
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![]() And did you even bother to read the whole thread? This isn't about building race cars. This is about low cost streetable performance gains for people who didn't get the gift of a 2.5l engine from the factory... |
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#16 |
Scooby Specialist
Member#: 964
Join Date: Feb 2000
Chapter/Region:
NWIC
Location: Bonney Lake, Wash. USA
Vehicle:'95 work in progress |
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#17 |
Scooby Newbie
Member#: 342420
Join Date: Jan 2013
Location: Killeen Texas
Vehicle:2005 |
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#18 | |
Scooby Guru
Member#: 6486
Join Date: May 2001
Chapter/Region:
MWSOC
Location: S.E. wisconsin
Vehicle:00 Impreza 2.5 RS Blue Ridge Pearl |
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#19 |
Scooby Specialist
Member#: 64494
Join Date: Jun 2004
Location: Australia
Vehicle:2001 V7 sti |
![]() Whilst your on the point of mixing and matchingI"ve often wondered about this combination.
EJ25 block for maximum bore capacity EJ20 crank , shorter stroke better rpm capacity custom long rods - improve rod ratio by having the taller ej25 block and the short stroke ej20 crank. The long rod combination improves rpm capacity. Overall capacity will still be close to 2.5L (about 2.4L I think). I really dont think the strength of the block is an issue after all turbo motors are putting out much higher hp's than n/a would ever be capable of and whens the last time you heard of a block failing? |
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#20 | |
Scooby Guru
Member#: 6486
Join Date: May 2001
Chapter/Region:
MWSOC
Location: S.E. wisconsin
Vehicle:00 Impreza 2.5 RS Blue Ridge Pearl |
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#21 |
Scooby Specialist
Member#: 60743
Join Date: Apr 2004
Chapter/Region:
MWSOC
Location: Fargo, ND
Vehicle:'95 Impreza L dirty and on jack stands |
![]() do what i amp planning:
phase II ej25 shortblock with the older dual port ej22 heads and the thick ej25 gasket. should get you right around 11.5:1. any higher and you would need to possibly add a piggyback to retard the ignition timing or add water injection or find a way to increase the fuel or all of the above. |
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#22 | |
Scooby Guru
Member#: 832
Join Date: Jan 2000
Chapter/Region:
RMIC
Location: Teh Ghetto Garage, CO
Vehicle:99 2.5RS, '85 911 '73 914 and 2012 BRZ |
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#23 | |
Scooby Newbie
Member#: 434949
Join Date: Nov 2015
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#24 | |
Scooby Newbie
Member#: 159603
Join Date: Sep 2007
Location: Chandler
Vehicle:2002 Subaru WRX Wago Pearl Matalic Silver |
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I will post the dyno sheet when i have it, and video I'm hoping will show my wide-band |
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#25 | |
Scooby Newbie
Member#: 442772
Join Date: Mar 2016
Chapter/Region:
MAIC
Location: Beautiful Downtown Goode, VA
Vehicle:2009 WRX sedan the faster charcoal grey |
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