Welcome to the North American Subaru Impreza Owners Club Tuesday July 22, 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 08-17-2011, 04:44 PM   #51
Turn in Concepts
NASIOC Vendor
 
Member#: 93646
Join Date: Aug 2005
Chapter/Region: MWSOC
Vehicle:
Many Track Records
Let us help you go fast!

Default

I'll chime in.

Quote:
Originally Posted by Crystal_Imprezav View Post
Nope, latest hiccup is this HC is causing me to get spark blowout way easier... Just put a fresh set of plugs in but I got some misfires yesterday so... At this point, I am over the whole high-compression hype. I am pretty sure there is a reason no other shops, tuners, etc have chimed in here... I am going to take it easy on this setup until I have time to swap the pistons out back to 8.5:1 Wiseco's.
We're getting that right now on low compression pistons.


Quote:
Originally Posted by berdugo View Post
Have you considered upgrading to CDI ignition to fix spark blow out?
Way ahead of you. I'll let you know how it turns out. Or just watch for our race reports.

Quote:
Originally Posted by Homemade WRX View Post
you'll also notice that no shops cam in and agreed that HC was a waste or that it didn't work
We'll know soon enough. Provided kelford can get me replacement cams soon enough....
* Registered users of the site do not see these ads.
Turn in Concepts is offline   Reply With Quote
Old 08-17-2011, 05:31 PM   #52
Crystal_Imprezav
Scooby Specialist
 
Member#: 84105
Join Date: Mar 2005
Chapter/Region: SCIC
Location: I'm a Newbie
Vehicle:
2005 Super Slow STi
CGM

Default

I had spark blowout problems at 8.5:1 at 30psi in 5th gear down the 1/4. Gapping my plugs down to .020 and adding a HKS DLI2 solved those problems (on E85).

Now, I have the blowout problem at 28psi on in 3rd+ gears not just 5th. I spent a lot of time testing and tuning this setup and it just isn't what it should be on paper. I suspect the short rod ratio has a lot to do with it. Would be very interested to see a MPS or Homemadewrx +4mm rod setup at 10:1.
Crystal_Imprezav is offline   Reply With Quote
Old 08-17-2011, 05:34 PM   #53
Crystal_Imprezav
Scooby Specialist
 
Member#: 84105
Join Date: Mar 2005
Chapter/Region: SCIC
Location: I'm a Newbie
Vehicle:
2005 Super Slow STi
CGM

Default

Quote:
Originally Posted by Homemade WRX View Post
you'll also notice that no shops cam in and agreed that HC was a waste or that it didn't work
I dare you to finish your car and test it out and/or send me a long rod motor (or parts) and I would be glad to prove you wrong
Crystal_Imprezav is offline   Reply With Quote
Old 08-17-2011, 11:23 PM   #54
n2oiroc
Scooby Specialist
 
Member#: 141952
Join Date: Feb 2007
Chapter/Region: MWSOC
Location: milwaukee, wi
Vehicle:
03 emo 8/2011 wrx

Default

i ran 9.5:1 with stock heads/cams in my 07 sti with a 35r and it made as much or more power than most of the low compression setups with cams and headwork.
n2oiroc is offline   Reply With Quote
Old 08-18-2011, 10:50 AM   #55
Crystal_Imprezav
Scooby Specialist
 
Member#: 84105
Join Date: Mar 2005
Chapter/Region: SCIC
Location: I'm a Newbie
Vehicle:
2005 Super Slow STi
CGM

Default

I assume you are talking about ARFab's 9.5:1 setup. If so, I ran it too. It is not really 9.5:1... Run the calcs on it. It is an OTS Arias piston from a RS. The compression height is altered and therefore only calcs out to a 8.5:1 piston not to mention anything thicker than a stock HG made it even lower in CR. That's why it was not much different than a LC setup...
Crystal_Imprezav is offline   Reply With Quote
Old 08-18-2011, 11:31 AM   #56
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

Quote:
Originally Posted by Crystal_Imprezav View Post
I dare you to finish your car and test it out and/or send me a long rod motor (or parts) and I would be glad to prove you wrong
GST runs 10:1 and run ethanol, Junior's Fozzy was on Manley '9.8:1' pistons IIRC, etc..anyone know what P&L is running?

Also, long rods behave differently from EJ25 engines, to an extent.

Do however need to hurry up with that wiring. I finally have my garage back for me and my project It's really sad that I've guys running them for years and my own car still isn't running for one reason or another. Oh well, I guess that's part of having customers. I'm not looking forward to wiring in the new EM.

Quote:
Originally Posted by Turn in Concepts View Post
We'll know soon enough. Provided kelford can get me replacement cams soon enough....
What cams did you guys need? and you never responded to me on the Wills ring stuff.
Homemade WRX is offline   Reply With Quote
Old 08-18-2011, 11:38 AM   #57
Turn in Concepts
NASIOC Vendor
 
Member#: 93646
Join Date: Aug 2005
Chapter/Region: MWSOC
Vehicle:
Many Track Records
Let us help you go fast!

Default

Quote:
Originally Posted by Homemade WRX View Post
GST runs 10:1 and run ethanol, Junior's Fozzy was on Manley '9.8:1' pistons IIRC, etc..anyone know what P&L is running?

Also, long rods behave differently from EJ25 engines, to an extent.

Do however need to hurry up with that wiring. I finally have my garage back for me and my project It's really sad that I've guys running them for years and my own car still isn't running for one reason or another. Oh well, I guess that's part of having customers. I'm not looking forward to wiring in the new EM.


What cams did you guys need? and you never responded to me on the Wills ring stuff.
The cams are a rather interesting story. Gimme a call and I'll tell you about it, but bottom line is my low friction motor project isn't going to happen this year as we needed the parts.

I did reply. I said I suspect I know what you're thinking and I have some heads you can use to lay out and test the tool path if you'd like.

OH! and I have some other ideas for you if you want to chat about them.
Turn in Concepts is offline   Reply With Quote
Old 08-18-2011, 11:53 AM   #58
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

yeah, I'll give you a call this afternoon...I somehow didn't get your reply or maybe I'm reading messages in my sleep now
Homemade WRX is offline   Reply With Quote
Old 08-18-2011, 02:47 PM   #59
juanmedina
Scooby Guru
 
Member#: 133146
Join Date: Nov 2006
Location: SC
Vehicle:
07 FPgreen 7.37@95
WRX VF39+E85 12.0, 121mph

Default

Quote:
Originally Posted by Homemade WRX View Post
GST runs 10:1 and run ethanol, Junior's Fozzy was on Manley '9.8:1' pistons IIRC, etc..anyone know what P&L is running?

Also, long rods behave differently from EJ25 engines, to an extent.

Do however need to hurry up with that wiring. I finally have my garage back for me and my project It's really sad that I've guys running them for years and my own car still isn't running for one reason or another. Oh well, I guess that's part of having customers. I'm not looking forward to wiring in the new EM.


What cams did you guys need? and you never responded to me on the Wills ring stuff.
IIRC P&L is running stock compression
juanmedina is online now   Reply With Quote
Old 08-18-2011, 02:59 PM   #60
Crystal_Imprezav
Scooby Specialist
 
Member#: 84105
Join Date: Mar 2005
Chapter/Region: SCIC
Location: I'm a Newbie
Vehicle:
2005 Super Slow STi
CGM

Default

GST is running 9:1 the last time I heard.

Junior had those '9.8:1's" in his car and if it was actually doing him any good, we probably would have seen something about it. He would/should have went faster on the stock turbo than he did before but the last update I saw on that car was it went rotated, and now he is selling/trading it to Paul@P&L.
Crystal_Imprezav is offline   Reply With Quote
Old 08-18-2011, 03:34 PM   #61
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

Quote:
Originally Posted by Crystal_Imprezav View Post
He would/should have went faster on the stock turbo than he did before .
care to clarify?

I know GST also has a couple of different engines that they use, so they may have a 9.0:1 for a certain race and 10:1 for another.
Transient response is something I'm assuming you don't care about for drag racing...?...may be part of their strategy in using higher CR for say, tight courses

Once again, I'll note that I don't care about EJ257 engines nor do I 'study' them. It's a good auto-x engine and is a design compromised for emissions as far as I see it. I'm just here to help spout ideas that may or may not be of use. Closest I get to them is sticking a +2 rod and lighter pistons into them

I agree that fundementally a big bore and short dwell with high compression do not work together. MBT timing window becomes very small...even smaller with more pressure. So hitting the target becomes the challenge. Theoretically it can make more power but here in the real world, I think you're finding the limitations of equipment, largely the ignition system.
There's a good SAE paper written up about the boosted Honda F1 engine and they address some of the fundemental issues that I just touched on. It's also just a fun engine to read about

IMO a dragrace EJ25 should get 'lower compression' and more boost.

Last edited by Homemade WRX; 08-18-2011 at 03:56 PM.
Homemade WRX is offline   Reply With Quote
Old 08-18-2011, 04:08 PM   #62
Crystal_Imprezav
Scooby Specialist
 
Member#: 84105
Join Date: Mar 2005
Chapter/Region: SCIC
Location: I'm a Newbie
Vehicle:
2005 Super Slow STi
CGM

Default

Yessss, I got Micah to semi-agree with me . What do you suggest I try next then, I am getting a little bit of a kick out of this. EG33??

Also, I agree for transient response and for a little bit of added off boost power, yes by all means upping the compression will help. However, so will a smaller turbo or hotside
Crystal_Imprezav is offline   Reply With Quote
Old 08-18-2011, 05:15 PM   #63
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

Did you ever answer if the cams were degreed correctly?
I'd like to see you put the cossies back on this setup and see the difference. A simple test with 1 variable.

Con's to using smaller hotside or turbo for the application is the loss of top end power...but I guess that's have to be weighed out with potential power loss from ignition/EM control at RPM.

If the cossies are still having issues, you'll have a better idea of what's going wrong. From there I'd really look into ignition.

EG33's are big/heavy girls but they are bigger and don't mind RPM
Homemade WRX is offline   Reply With Quote
Old 08-18-2011, 05:58 PM   #64
Crystal_Imprezav
Scooby Specialist
 
Member#: 84105
Join Date: Mar 2005
Chapter/Region: SCIC
Location: I'm a Newbie
Vehicle:
2005 Super Slow STi
CGM

Default

Quote:
Originally Posted by Homemade WRX
Did you ever answer if the cams were degreed correctly?
I'd like to see you put the cossies back on this setup and see the difference. A simple test with 1 variable.

Con's to using smaller hotside or turbo for the application is the loss of top end power...but I guess that's have to be weighed out with potential power loss from ignition/EM control at RPM.

If the cossies are still having issues, you'll have a better idea of what's going wrong. From there I'd really look into ignition.

EG33's are big/heavy girls but they are bigger and don't mind RPM
The cosworth Cams are currently in my buddies car. Really if I'm going to pull the motor out, I would rather just swap the pistons out... If the power comes back then I know it's the hc anyways.

Yes cams were degreed properly.

For me the hc did the same thing as a small hot side. Better transient response and off boost power but lost topend...
Crystal_Imprezav is offline   Reply With Quote
Old 08-18-2011, 06:53 PM   #65
Turn in Concepts
NASIOC Vendor
 
Member#: 93646
Join Date: Aug 2005
Chapter/Region: MWSOC
Vehicle:
Many Track Records
Let us help you go fast!

Default

Quote:
Originally Posted by Homemade WRX View Post
yeah, I'll give you a call this afternoon...I somehow didn't get your reply or maybe I'm reading messages in my sleep now
Sorry I sounded so distracted on the phone this afternoon. Too much going on, and Tony is out for a long weekend.

As to the thread - we have two different hot sides we run for the turbo depending upon the track. We also adjust redline. Lower for the small one,and higher for the big one. No need to spin the small one all the way out if it doesn't make power there.
Turn in Concepts is offline   Reply With Quote
Old 08-19-2011, 05:10 PM   #66
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

Quote:
Originally Posted by Turn in Concepts View Post
Sorry I sounded so distracted on the phone this afternoon. Too much going on, and Tony is out for a long weekend.
Not a problem, you sounded busy. I was bored as I just kicked off an hour long test and was caught up no data.


Quote:
Originally Posted by Crystal_Imprezav View Post
The cosworth Cams are currently in my buddies car. Really if I'm going to pull the motor out, I would rather just swap the pistons out... If the power comes back then I know it's the hc anyways.
You could still have the ignition short comings be a problem with Cossie cams and be down on power. So....
Homemade WRX is offline   Reply With Quote
Old 08-22-2011, 05:56 PM   #67
SW00P_G
Scooby Specialist
 
Member#: 5591
Join Date: Apr 2001
Chapter/Region: MWSOC
Location: Westerville, Ohio, USA
Vehicle:
2002 WRX
EJ257 Gt35r

Default

Quote:
Originally Posted by Homemade WRX View Post
You could still have the ignition short comings be a problem with Cossie cams and be down on power. So....

┐HUH?
SW00P_G is offline   Reply With Quote
Old 08-22-2011, 07:18 PM   #68
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

Quote:
Originally Posted by SW00P_G View Post
┐HUH?
If he were to install the cossie cams and still be down on power, we still don't know if the ignition system is the weakness...thus we haven't learned the actual issue he is having.
Homemade WRX is offline   Reply With Quote
Old 08-22-2011, 08:42 PM   #69
02h20
Scooby Newbie
 
Member#: 130079
Join Date: Oct 2006
Chapter/Region: Tri-State
Location: Precision Tuning Built
Vehicle:
2006 STI 9.7@148
CleoTuned@PrecisionTuning

Default

We made 741 on manley HC pistons (9.8:1) stock ports and stock valves with BC280 cams. We made 691 on LC pistons with fully ported heads bigger valves and more bigger cams with the same turbo. 691 was on c16 741 was on e85. Also around the same boost level. The manley pistons work from what I have seen. What exhaust housing are you using on your turbo?
02h20 is offline   Reply With Quote
Old 08-22-2011, 10:01 PM   #70
DJIMPREZA
Scooby Specialist
 
Member#: 1199
Join Date: Apr 2000
Location: Caracas, Venezuela
Vehicle:
1994 Supra+1K, 22b
alike, 07STI

Default

Hi Jeff, we cosworth released their 9.2 engines, we bought a lot of them, maybe 5 at once, then we went up on another one with 9.5 to 1 cr, after a while we all end up again to 8.5 being the most street/drag friendly. From my recalls I could see how high egts were climbing on hc motors inducing a lot of exhaust manifold pressure (pressure ratio quite higher from low comp) it might be inducing exhaust gas reversing and/or limiting final flow... I am following your results, keep it, DJ
DJIMPREZA is offline   Reply With Quote
Old 08-22-2011, 10:48 PM   #71
juanmedina
Scooby Guru
 
Member#: 133146
Join Date: Nov 2006
Location: SC
Vehicle:
07 FPgreen 7.37@95
WRX VF39+E85 12.0, 121mph

Default

The only way to test that high compression really works is a back to back test with the same mods. As of right now it seems 50/50.
juanmedina is online now   Reply With Quote
Old 08-22-2011, 11:02 PM   #72
project_skyline
Scooby Specialist
 
Member#: 153880
Join Date: Jul 2007
Chapter/Region: RMIC
Location: Western Slope, Colorado
Vehicle:
03 Evo VIII
2011 STI

Default

Quote:
Originally Posted by juanmedina View Post
The only way to test that high compression really works is a back to back test with the same mods. As of right now it seems 50/50.
Just because high compression isn't working for one person in this particular thread and supposedly a couple others doesn't mean it doesn't work.

Just means they haven't figured out what isn't working right with it.
project_skyline is offline   Reply With Quote
Old 08-22-2011, 11:34 PM   #73
maxpowr
Scooby Guru
 
Member#: 159243
Join Date: Sep 2007
Chapter/Region: Tri-State
Location: medford nj 08055
Vehicle:
sg3 Turbo Tek Tuned
Hakt Ecu e85 30r 6spd

Default

mikey will show you guys how its done.
maxpowr is offline   Reply With Quote
Old 08-23-2011, 12:01 AM   #74
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

Quote:
Originally Posted by juanmedina View Post
The only way to test that high compression really works is a back to back test with the same mods. As of right now it seems 50/50.
and then it still doesn't say weather it works or not. It may simply require large primaries or AR on the turbine.

In an engine, NOTHING is cut and dry. Everything is connected.
Homemade WRX is offline   Reply With Quote
Old 08-23-2011, 12:57 AM   #75
juanmedina
Scooby Guru
 
Member#: 133146
Join Date: Nov 2006
Location: SC
Vehicle:
07 FPgreen 7.37@95
WRX VF39+E85 12.0, 121mph

Default

Quote:
Originally Posted by project_skyline View Post
Just because high compression isn't working for one person in this particular thread and supposedly a couple others doesn't mean it doesn't work.

Just means they haven't figured out what isn't working right with it.
or maybe It just simply means that it doesn't work

Quote:
Originally Posted by maxpowr View Post
mikey will show you guys how its done.
\/

Quote:
Originally Posted by Homemade WRX View Post
care to clarify?

I know GST also has a couple of different engines that they use, so they may have a 9.0:1 for a certain race and 10:1 for another.
Transient response is something I'm assuming you don't care about for drag racing...?...may be part of their strategy in using higher CR for say, tight courses

Once again, I'll note that I don't care about EJ257 engines nor do I 'study' them. It's a good auto-x engine and is a design compromised for emissions as far as I see it. I'm just here to help spout ideas that may or may not be of use. Closest I get to them is sticking a +2 rod and lighter pistons into them

I agree that fundementally a big bore and short dwell with high compression do not work together. MBT timing window becomes very small...even smaller with more pressure. So hitting the target becomes the challenge. Theoretically it can make more power but here in the real world, I think you're finding the limitations of equipment, largely the ignition system.
There's a good SAE paper written up about the boosted Honda F1 engine and they address some of the fundemental issues that I just touched on. It's also just a fun engine to read about

IMO a dragrace EJ25 should get 'lower compression' and more boost.
Quote:
Originally Posted by Homemade WRX View Post
and then it still doesn't say weather it works or not. It may simply require large primaries or AR on the turbine.

In an engine, NOTHING is cut and dry. Everything is connected.
If it works the promoters of this high compression engine should device a test that show that it works... Obviously I hope it work who doesn't want better response and more power.

The only impressive high compression setup that I have seen is Md05Sti's, other than that one there is nothing. And that car hasn't even run a good pass thanks to the tranny .
juanmedina is online now   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
High compression e85 big bore questions 5lipstream Built Motor Discussion 4 07-02-2011 09:39 PM
Wtb sti window spoiler and a big turbo neversummer489 NWIC Private Classifieds 10 03-04-2010 09:52 PM
FS: NC My 2001 RS w/ High compression motor, and other parts Whiteghost 2.5 Private Vehicle 'For Sale' Classifieds 23 10-17-2009 09:16 PM
Big boost, big cams, high compression? Drink Built Motor Discussion 18 03-13-2007 06:02 PM


All times are GMT -4. The time now is 03:47 PM.


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.