Welcome to the North American Subaru Impreza Owners Club Wednesday November 26, 2014
Home Forums WikiNASIOC Products Store Modifications Upgrade Garage
NASIOC
Here you can view your subscribed threads, work with private messages and edit your profile and preferences Home Registration is free! Visit the NASIOC Store NASIOC Rules Search Find other members Frequently Asked Questions Calendar Archive NASIOC Upgrade Garage Logout
Go Back   NASIOC > NASIOC Technical > Built Motor Discussion

Welcome to NASIOC - The world's largest online community for Subaru enthusiasts!
Welcome to the NASIOC.com Subaru forum.

You are currently viewing our forum as a guest, which gives you limited access to view most discussions and access our other features. By joining our community, free of charge, you will have access to post topics, communicate privately with other members (PM), respond to polls, upload content and access many other special features. Registration is free, fast and simple, so please join our community today!

If you have any problems with the registration process or your account login, please contact us.
* Registered users of the site do not see these ads.
Reply
 
Thread Tools Display Modes
Old 01-01-2007, 10:04 PM   #1
dexterous
Scooby Guru
 
Member#: 23553
Join Date: Aug 2002
Chapter/Region: MAIC
Location: Slippery Rock, PA
Vehicle:
2005 STI - Insanity!
2014 WRX - Daily

Default Will JDM STI AVCS cams in USDM STI AVCS heads?

I have been searching for a good while now and I have found lots of info about using AVCS JDM cams in non-AVCS USDM 02-05 WRX heads but nothing about using JDM AVCS cams in the USDM STI AVCS heads.

Will JDM AVCS cams fit in the USDM STI AVCS heads and work correctly assuming proper tuning and supporting mods? To me, supporting mods to the heads would include valvetrain modifications to support 8K RPMs and porting.

I don't have huge power goals or anything. I would be very very happy with a well running motor making 375-400whp and the ability to crank to eight grand without the power dropping like a rock form the early sixes.
* Registered users of the site do not see these ads.
dexterous is offline   Reply With Quote
Old 01-02-2007, 04:13 AM   #2
Marnix
Scooby Specialist
 
Member#: 51480
Join Date: Dec 2003
Chapter/Region: International
Location: The Netherlands
Vehicle:
1984 AM5, 1994 BC4,
2010 BR5

Default

Yes, they fit. But JDM STI cams have less lift and more duration compared to USDM STI cams.
Marnix is offline   Reply With Quote
Old 01-02-2007, 10:38 AM   #3
Wrinkleboi
Top Scoob 006
 
Member#: 14424
Join Date: Jan 2002
Chapter/Region: South East
Location: Stuart, FL
Vehicle:
BugI w/ 07 STi Swap
www.TriStateTuners.com

Default

less lift?
Wrinkleboi is offline   Reply With Quote
Old 01-02-2007, 12:48 PM   #4
S L O W W R X
Scooby Specialist
 
Member#: 95109
Join Date: Sep 2005
Default

The cam sensor pick ups are completely diffrent, I'm not sure if you can make the avcs work
S L O W W R X is offline   Reply With Quote
Old 01-03-2007, 11:43 AM   #5
dexterous
Scooby Guru
 
Member#: 23553
Join Date: Aug 2002
Chapter/Region: MAIC
Location: Slippery Rock, PA
Vehicle:
2005 STI - Insanity!
2014 WRX - Daily

Default

Interesting. So does anybody have any recommendations for CAM options? Am I correct in thinking that I would need cams to have a well rounded motor spinning to 8K?
dexterous is offline   Reply With Quote
Old 01-03-2007, 10:45 PM   #6
zanderspeed
Scooby Newbie
 
Member#: 72818
Join Date: Oct 2004
Chapter/Region: SCIC
Location: San Diego
Vehicle:
2002 Bugeye
EJ25 | FPGreen

Default

The pick ups are completely different. Why not purchase a set of aftermarket avcs cams?
zanderspeed is offline   Reply With Quote
Old 01-04-2007, 12:12 AM   #7
wrxfactor
Scooby Specialist
 
Member#: 49978
Join Date: Dec 2003
Chapter/Region: NESIC
Location: Shrewsbury, MA
Vehicle:
2002 WRX w/ JDM STi
6spd, EJ255, VF39 & EWG

Default

Quote:
Originally Posted by dexterous View Post
Interesting. So does anybody have any recommendations for CAM options? Am I correct in thinking that I would need cams to have a well rounded motor spinning to 8K?
If you are spinning to 8k I'd get bigger cams than stock, I don't care what stock motor they were in.
wrxfactor is offline   Reply With Quote
Old 01-04-2007, 09:11 PM   #8
dexterous
Scooby Guru
 
Member#: 23553
Join Date: Aug 2002
Chapter/Region: MAIC
Location: Slippery Rock, PA
Vehicle:
2005 STI - Insanity!
2014 WRX - Daily

Default

Quote:
Originally Posted by zanderspeed View Post
The pick ups are completely different. Why not purchase a set of aftermarket avcs cams?
Sure, recommend something and I will look into it.
dexterous is offline   Reply With Quote
Old 01-04-2007, 10:33 PM   #9
zanderspeed
Scooby Newbie
 
Member#: 72818
Join Date: Oct 2004
Chapter/Region: SCIC
Location: San Diego
Vehicle:
2002 Bugeye
EJ25 | FPGreen

Default

zanderspeed is offline   Reply With Quote
Old 01-05-2007, 02:52 AM   #10
BLUE STINGER
Scooby Specialist
 
Member#: 84206
Join Date: Mar 2005
Default

Quote:
Originally Posted by Wrinkleboi View Post
less lift?
That's how high the the valves open and the duration is how long they stay open.

Ron
BLUE STINGER is offline   Reply With Quote
Old 01-05-2007, 03:43 AM   #11
Wrinkleboi
Top Scoob 006
 
Member#: 14424
Join Date: Jan 2002
Chapter/Region: South East
Location: Stuart, FL
Vehicle:
BugI w/ 07 STi Swap
www.TriStateTuners.com

Default

yeah i thought they had more lift and more duration... but maybe i'm just ASSuming. i know they are more aggressive than usdm, but maybe that can be achieved still with less lift but more duration? i'm a cam noob.
Wrinkleboi is offline   Reply With Quote
Old 01-05-2007, 08:31 AM   #12
Assami
Scooby Newbie
 
Member#: 130699
Join Date: Oct 2006
Location: a U.S in Saudi Arabia
Vehicle:
2005 STI JDM 2.0L
Blue 315whp

Default

yes they will fit, the only thing youl not have is the mid rang power that the AVCS will normally supply you with.

with AVCS the timing will be different between RPMs.
Assami is offline   Reply With Quote
Old 01-07-2007, 06:45 AM   #13
Marnix
Scooby Specialist
 
Member#: 51480
Join Date: Dec 2003
Chapter/Region: International
Location: The Netherlands
Vehicle:
1984 AM5, 1994 BC4,
2010 BR5

Default

It seems there are two types of pick-up for the AVCS sensor on the rear end of the cams. The JDM cams have 4 positive signal pick-up points on the cam, whereas the USDM cams seem to have negative pick-up points (slots). Can anyone comfirm this?

I'm running JDM Legacy EJ20X/Y heads/cams on a USDM Legacy EJ255 ECU and loom, with AVCS working, meaning the USDM cams must have the same slots as the JDM Legacy EJ20X/Y have (so the JDM Legacy EJ20X/Y cams differ from for instance JDM STI cams regarding AVCS pick-up).
Marnix is offline   Reply With Quote
Old 01-07-2007, 02:45 PM   #14
Dasani
Top Scoob 005
 
Member#: 58098
Join Date: Mar 2004
Chapter/Region: TXIC
Location: Houston, Texas
Vehicle:
10.4 @ 137.46mph
Cosworth, TSR70, MZM Tune

Default

The USDM STi AVCS cams do indeed have slots at the rear. I forget how many though...

-D
Dasani is offline   Reply With Quote
Old 01-07-2007, 10:50 PM   #15
wrxfactor
Scooby Specialist
 
Member#: 49978
Join Date: Dec 2003
Chapter/Region: NESIC
Location: Shrewsbury, MA
Vehicle:
2002 WRX w/ JDM STi
6spd, EJ255, VF39 & EWG

Default

Quote:
Originally Posted by Marnix View Post
It seems there are two types of pick-up for the AVCS sensor on the rear end of the cams. The JDM cams have 4 positive signal pick-up points on the cam, whereas the USDM cams seem to have negative pick-up points (slots). Can anyone comfirm this?

I'm running JDM Legacy EJ20X/Y heads/cams on a USDM Legacy EJ255 ECU and loom, with AVCS working, meaning the USDM cams must have the same slots as the JDM Legacy EJ20X/Y have (so the JDM Legacy EJ20X/Y cams differ from for instance JDM STI cams regarding AVCS pick-up).
That would have been great to know when MZM was working on my WRX with EJ20X swap that that couldn't get to run correctly without the proper ECU.
wrxfactor is offline   Reply With Quote
Old 01-08-2007, 07:33 AM   #16
Marnix
Scooby Specialist
 
Member#: 51480
Join Date: Dec 2003
Chapter/Region: International
Location: The Netherlands
Vehicle:
1984 AM5, 1994 BC4,
2010 BR5

Default

I almost ordered JUN AVCS intake cams for a customer's engine which runs EJ20X/Y cams on a USDM MY05 Legacy GT ECU.

I'm now discussing with JUN if they can supply the cams with the other AVCS pick-up pattern. If they can't, I will use standard Subaru intake cams off a MY07 Legacy 2.0R. Those are atmo cams with AVCS, 248 degree (standard turbo AVCS cam is around 240) and 9.8 mm lift. The atmo engine makes 168 ps @ 6800 rpm.

I think the difference (slots or ribs) has to do with solid cams (cast ribs) or the latest hollow cams (slots machined into them).

Last edited by Marnix; 01-08-2007 at 07:42 AM.
Marnix is offline   Reply With Quote
Old 01-08-2007, 12:33 PM   #17
zanderspeed
Scooby Newbie
 
Member#: 72818
Join Date: Oct 2004
Chapter/Region: SCIC
Location: San Diego
Vehicle:
2002 Bugeye
EJ25 | FPGreen

Default

The pickup points and sensors are completely different. The JDM are two-wire magentic sensors. The USDM STI sensors are 3-wire hall-effect sensors.
zanderspeed is offline   Reply With Quote
Old 07-31-2008, 09:36 AM   #18
WhiteKnight
Scooby Newbie
 
Member#: 56133
Join Date: Feb 2004
Vehicle:
2004 Euro spec Sti
Black - Rotated gt3037s

Default

EJ25 heads + cossy euro/japan spec cams + euro spec ecu + euro AVCS sensors

Would these combo work?

AVCS solenoid bracket needs a little work but i think it is ok.

Any ideas?

Thanks
WhiteKnight is offline   Reply With Quote
Old 04-27-2011, 12:50 AM   #19
Homemade WRX
Scooby Guru
 
Member#: 33782
Join Date: Mar 2003
Chapter/Region: MAIC
Location: 3MI Racing LLC
Vehicle:
96 bastard child
search FIRST, then PM!!!

Default

white knight, did you ever figure out if the combo worked? I'm about to buy a 207 just to measure things up and see if the JDM ecu, cams, sensor and solenoids can be used...basically all the parts that are easy to buy. Heads are hard to come buy and guys seem to think they are gold or give ZJs.
Homemade WRX is offline   Reply With Quote
Old 04-27-2011, 09:51 AM   #20
biodude
Scooby Specialist
 
Member#: 271720
Join Date: Jan 2011
Chapter/Region: Tri-State
Location: NEPA
Default

Im curious as well for the same reasons.

Last edited by biodude; 04-27-2011 at 10:00 AM.
biodude is offline   Reply With Quote
Old 04-27-2011, 11:16 AM   #21
seanathanq83
Scooby Guru
 
Member#: 173241
Join Date: Feb 2008
Chapter/Region: TXIC
Location: Houston, Tx
Vehicle:
2002 s256 twinscroll
now with one more gear

Default

I have a ver8 jdm engine, the cams profiles for the pickups are positive, not negative like the usdm, I don't see why you couldn't use jdm cams in 2.5 heads as long as you used the ecu that was needed as well the holes should be the same where the cams bolt up, so for building an engine it would be ok, or for doing a hybrid, just remember you need everything including the jdm engine harness., also they have more duration and less lift which aids in higher rpms
seanathanq83 is offline   Reply With Quote
Old 04-27-2011, 11:29 AM   #22
Homemade WRX
Scooby Guru
 
Member#: 33782
Join Date: Mar 2003
Chapter/Region: MAIC
Location: 3MI Racing LLC
Vehicle:
96 bastard child
search FIRST, then PM!!!

Default

I know the difference in sensor type and cam trigger but I'm wondering as to placement in degrees relative to crank the difference is in trigger times and sensor placement...also no one has been able to clarify (including Dave @ RalliSpec, Steve at IA performance) if the sensors can fit. Though Dave was saying that he doesn't think JDM sensors will physically fit without some machine work.

I've also brought this thread back from the dead. I hope Waxed can be more specific on sensor alignment.

http://forums.nasioc.com/forums/showthread.php?t=992216
Homemade WRX is offline   Reply With Quote
Old 04-29-2011, 09:09 PM   #23
nedalrabadi
Scooby Newbie
 
Member#: 244358
Join Date: Apr 2010
Chapter/Region: International
Location: JORDAN
Vehicle:
1996 impreza
orange & black

Default

Quote:
Originally Posted by Marnix View Post
I almost ordered JUN AVCS intake cams for a customer's engine which runs EJ20X/Y cams on a USDM MY05 Legacy GT ECU.

I'm now discussing with JUN if they can supply the cams with the other AVCS pick-up pattern. If they can't, I will use standard Subaru intake cams off a MY07 Legacy 2.0R. Those are atmo cams with AVCS, 248 degree (standard turbo AVCS cam is around 240) and 9.8 mm lift. The atmo engine makes 168 ps @ 6800 rpm.

I think the difference (slots or ribs) has to do with solid cams (cast ribs) or the latest hollow cams (slots machined into them).
please any info about the EJ20X
are they like the EJ205 or EJ207 ?
nedalrabadi is offline   Reply With Quote
Old 04-29-2011, 10:39 PM   #24
seanathanq83
Scooby Guru
 
Member#: 173241
Join Date: Feb 2008
Chapter/Region: TXIC
Location: Houston, Tx
Vehicle:
2002 s256 twinscroll
now with one more gear

Default

I have the jdm Cam sensors, let me see if I can either find usdm sti Cam sensors or if I can find a 2.5 to try them out, they look the same, I can snap a pic tonight
seanathanq83 is offline   Reply With Quote
Old 04-30-2011, 03:11 PM   #25
Homemade WRX
Scooby Guru
 
Member#: 33782
Join Date: Mar 2003
Chapter/Region: MAIC
Location: 3MI Racing LLC
Vehicle:
96 bastard child
search FIRST, then PM!!!

Default

if you can get a side by side and actual dimensions (tip length from shoulder, offset from center of bolt hold to center of pick up, and tip diameter).

I think the big issue is going to come with alignment of heads and cams triggers.
Homemade WRX is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
JDM avcs cams vs. USDM avcs cams are they interchangable? cubuff Built Motor Discussion 13 12-17-2008 12:41 PM
Analysis of Cosworth AVCS cams vs USDM STI cams bboy Built Motor Discussion 89 06-18-2008 04:48 PM
Non-AVCS Cams in STI Heads SloRice Built Motor Discussion 3 10-07-2006 04:18 PM
STI v5-6 cams in USDM ej20t markk26 Subaru Conversions 3 10-14-2004 10:07 PM
Trade JDM Spec C cams for USDM Sti Cams Julio Private 'For Sale' Classifieds 0 11-16-2003 10:09 PM


All times are GMT -4. The time now is 04:07 AM.


Powered by vBulletin® Version 3.7.0
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
Powered by Searchlight © 2014 Axivo Inc.
Copyright ©1999 - 2014, North American Subaru Impreza Owners Club, Inc.