Welcome to the North American Subaru Impreza Owners Club Saturday November 28, 2020
Home Forums Images WikiNASIOC Products Store Modifications Upgrade Garage
NASIOC
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.







* As an Amazon Associate I earn from qualifying purchases. 
* Registered users of the site do not see these ads. 
Reply
 
Thread Tools Display Modes
Old 11-15-2013, 04:32 PM   #1
KillerBMotorsport
NASIOC Vendor
 
Member#: 198281
Join Date: Dec 2008
Chapter/Region: MAIC
Location: Virginia
Vehicle:
2005 WRX/STi
WRB of course

Default Why you don't need GR (11mm) Oil Pump in GD (10mm) Engine

* Registered users of the site do not see these ads.
KillerBMotorsport is offline   Reply With Quote
Sponsored Links
* Registered users of the site do not see these ads.
Old 11-15-2013, 04:36 PM   #2
KillerBMotorsport
NASIOC Vendor
 
Member#: 198281
Join Date: Dec 2008
Chapter/Region: MAIC
Location: Virginia
Vehicle:
2005 WRX/STi
WRB of course

Default

Opening clearances by a couple thousandths is nothing compared to dual AVCS requirements, and certainly doesn't require the extra +30% in flow that the 11mm pump is capable of putting out.
KillerBMotorsport is offline   Reply With Quote
Old 11-15-2013, 04:38 PM   #3
KillerBMotorsport
NASIOC Vendor
 
Member#: 198281
Join Date: Dec 2008
Chapter/Region: MAIC
Location: Virginia
Vehicle:
2005 WRX/STi
WRB of course

Default

Plus running an aftermarket ball bearing turbo uses a smaller oil restrictor, requiring less flow.
KillerBMotorsport is offline   Reply With Quote
Old 11-15-2013, 04:47 PM   #4
morrocco88
Scooby Specialist
 
Member#: 104098
Join Date: Jan 2006
Chapter/Region: NWIC
Location: Eastern WA
Vehicle:
97' LGT 2.3 Dstroke
Rotated BW S256 6speed

Default

Where is that oil pressure gauge installed? Idiot light plug right above the pump?
morrocco88 is offline   Reply With Quote
Old 11-15-2013, 04:54 PM   #5
Scuby04STi
Scooby Specialist
 
Member#: 328635
Join Date: Aug 2012
Chapter/Region: NWIC
Location: Portland*
Vehicle:
2004 STi GTX3076R
Rally Blue

Default

I have thought this is an interesting topic for awhile now because its nearly a default to get an 11mm pump if someone builds a block these days.

I was criticized over and over about getting the 10mm, seeing "oiling is such an issue" on our motors

Pretty sure the pump is FAR from the weak link. Rev her to 8k everyday, have your pan/pick-up/baffle along with the Perrin AOS and my oil system seems to be issueless thus far (8500 miles going hard).
Scuby04STi is offline   Reply With Quote
Old 11-15-2013, 05:30 PM   #6
mboulton
Scooby Newbie
 
Member#: 174433
Join Date: Mar 2008
Default

More details about setup please. I don't see that kind of drop on my built 2008.
mboulton is offline   Reply With Quote
Old 11-15-2013, 05:39 PM   #7
Paidfor
Scooby Specialist
 
Member#: 267815
Join Date: Dec 2010
Chapter/Region: South East
Location: LSx allll done..need headers
Vehicle:
Be in awe
dont hate .)

Default

How does having too much flow make the pressure drop?



Confused about that gauge fluctuating..............never seen this.Wouldnt this be more of a cracked pickup issue?
Paidfor is offline   Reply With Quote
Old 11-15-2013, 05:58 PM   #8
Th3Franz
Scooby Specialist
 
Member#: 37146
Join Date: May 2003
Chapter/Region: MWSOC
Location: CA
Vehicle:
2005 Legacy GT
Stage tree fitty

Default

My single AVCS engine does not exhibit that behavior with an 11 mm pump. Oil pressure is rock steady and in line where it should be. Ball bearing turbo also.
My oil pressure gauge sender is installed at the top of the block, where the factory sensor used to be.
Th3Franz is offline   Reply With Quote
Old 11-15-2013, 06:01 PM   #9
subydude
Scooby Guru
 
Member#: 80649
Join Date: Jan 2005
Chapter/Region: South East
Location: Columbia, SC
Vehicle:
2000 2.5 Auto-X RSTi
Dusty

Default

That's not a pump issue, that's a gauge sender issue. You likely have a wire grounding out, or a sender that's having issues. Oil would not fluctuate like that at constant low revs.

The only other issue MIGHT be the by-pass valve sticking closed in the pump, but that seems rather unlikely.
subydude is online now   Reply With Quote
Old 11-15-2013, 06:36 PM   #10
the suicidal eggroll
Scooby Guru
 
Member#: 51961
Join Date: Jan 2004
Chapter/Region: RMIC
Location: Broomfield, CO
Vehicle:
2005 STi
2012 WRX

Default

The pressure on my '05 doesn't do that. It does fluctuate a bit, but it's more of a slow oscillation up and down a few psi. The stock 10mm pump had the exact same oscillation on my car too, it was nothing new with the 11mm that I installed with the built motor. The video in the OP looks like more of a gauge or bypass problem to me.
the suicidal eggroll is offline   Reply With Quote
Old 11-15-2013, 08:00 PM   #11
subydude
Scooby Guru
 
Member#: 80649
Join Date: Jan 2005
Chapter/Region: South East
Location: Columbia, SC
Vehicle:
2000 2.5 Auto-X RSTi
Dusty

Default

Quote:
Originally Posted by the suicidal eggroll View Post
The pressure on my '05 doesn't do that. It does fluctuate a bit, but it's more of a slow oscillation up and down a few psi. The stock 10mm pump had the exact same oscillation on my car too, it was nothing new with the 11mm that I installed with the built motor. The video in the OP looks like more of a gauge or bypass problem to me.
The oscillation is normal since the pump "spurts" kind of like a heart. If the gauge doesn't have a reducer or isn't programmed for that you'll always see some oscillation.

Last edited by subydude; 11-15-2013 at 08:20 PM.
subydude is online now   Reply With Quote
Old 11-15-2013, 08:19 PM   #12
Justin V
Scooby Specialist
 
Member#: 98747
Join Date: Oct 2005
Chapter/Region: South East
Location: GA
Vehicle:
07 WRX
WRB

Default

The video is a GR by the gauge cluster, so I really can't tell what it is trying to prove.

My friends oil pressure was a bit weird with her build and prosport gauge. It dropped scary low sometimes then seemed to perk up and stablize.

I've heard of the bypass valve sticking too, don't know how common it is though. My next pump will be taken apart and checked before install.
Justin V is offline   Reply With Quote
Old 11-15-2013, 10:49 PM   #13
KillerBMotorsport
NASIOC Vendor
 
Member#: 198281
Join Date: Dec 2008
Chapter/Region: MAIC
Location: Virginia
Vehicle:
2005 WRX/STi
WRB of course

Default

Some great speculation and guesses here. Lets see if we can fill in some blanks

Quote:
Originally Posted by morrocco88 View Post
Where is that oil pressure gauge installed? Idiot light plug right above the pump?
Yes. This is the best place as it's immediately at the pump's output before distribution to the different galleries.

Quote:
Originally Posted by Scuby04STi View Post
I have thought this is an interesting topic for awhile now because its nearly a default to get an 11mm pump if someone builds a block these days.

I was criticized over and over about getting the 10mm, seeing "oiling is such an issue" on our motors

Pretty sure the pump is FAR from the weak link. Rev her to 8k everyday, have your pan/pick-up/baffle along with the Perrin AOS and my oil system seems to be issueless thus far (8500 miles going hard).
^ Rock on Mr Man!

Quote:
Originally Posted by mboulton View Post
More details about setup please. I don't see that kind of drop on my built 2008.
Setup is stage II+ 2012 STi. If you emulate these conditions I'm very certain you'll see nearly the exact same thing.

Quote:
Originally Posted by Paidfor View Post
How does having too much flow make the pressure drop?

Confused about that gauge fluctuating..............never seen this.Wouldnt this be more of a cracked pickup issue?
Too much flow doesn't make the pressure drop. The AVCS exhaust cam solenoid DOES cause the pressure drop. What you don't see in the vid is that I am at cruise and then I lift off. AVCS solenoids open, pressure drops 40psi!

Quote:
Originally Posted by Th3Franz View Post
My single AVCS engine does not exhibit that behavior with an 11 mm pump. Oil pressure is rock steady and in line where it should be. Ball bearing turbo also.
My oil pressure gauge sender is installed at the top of the block, where the factory sensor used to be.
It won't drop because you don't have dual AVCS, but because you ARE pumping +30% more oil, it's just going through your bypass valve. Adding heat you wouldn't normally add, and at high RPMs you can experience a pressure drop due to aeration, unless the pump/bypass has been properly ported

Quote:
Originally Posted by subydude View Post
That's not a pump issue, that's a gauge sender issue. You likely have a wire grounding out, or a sender that's having issues. Oil would not fluctuate like that at constant low revs.

The only other issue MIGHT be the by-pass valve sticking closed in the pump, but that seems rather unlikely.
No sender issue, no gauge issue. It's got a Killer B Pickup installed of course Everything works just as it should.

Quote:
Originally Posted by the suicidal eggroll View Post
The pressure on my '05 doesn't do that. It does fluctuate a bit, but it's more of a slow oscillation up and down a few psi. The stock 10mm pump had the exact same oscillation on my car too, it was nothing new with the 11mm that I installed with the built motor. The video in the OP looks like more of a gauge or bypass problem to me.
Again, you won't see those fluctuation with a GD because there is no dual AVCS. Fluctuations you see are likely due to the bypass regulating pressure.

Quote:
Originally Posted by subydude View Post
The oscillation is normal since the pump "spurts" kind of like a heart. If the gauge doesn't have a reducer or isn't programmed for that you'll always see some oscillation.
Observed oscillations are due to bypass valve operation typically. The pump squeezes oil MANY times per revolution of the crank. It happens much too fast to see or for a typical gauge/sensor to react to.

Quote:
Originally Posted by Justin V View Post
The video is a GR by the gauge cluster, so I really can't tell what it is trying to prove.

My friends oil pressure was a bit weird with her build and prosport gauge. It dropped scary low sometimes then seemed to perk up and stablize.

I've heard of the bypass valve sticking too, don't know how common it is though. My next pump will be taken apart and checked before install.
Just showing the reason an 11mm pump IS needed in GRs
KillerBMotorsport is offline   Reply With Quote
Old 11-15-2013, 11:01 PM   #14
dstroy
Scooby Specialist
 
Member#: 283711
Join Date: May 2011
Chapter/Region: NESIC
Location: Newport
Vehicle:
2012 STI sedan
Black with scratches

Default

Mine doesn't drop that much when I lift off of the throttle, more like 20 psi. I make around 90 psi at redline, 80 psi at any rpm above 2800rpm. I'm not concerned with the oil pressure dropping on throttle lift. Yeah it sounds scary, but it really isn't, and it doesn't drop the instant you lift. You have to lift and engine brake for a while. Even then, the load on the engine is very low, it's spinning fast but there isn't nearly as much bearing load so you don't need the pressure that you would if you were WOT. When the exhaust side fully retards it helps slow the car down faster. 30% more oil flow makes up for the pressure drop.
dstroy is offline   Reply With Quote
Old 11-15-2013, 11:16 PM   #15
vicious_fishes
Scooby Guru
 
Member#: 158864
Join Date: Sep 2007
Location: Aussieland
Vehicle:
2003 SOHC destroker

Default

fwiw i ran the stock 8mm pump when i boosted my N/A EJ251. would only lose oil pressure once the oil got really, really hot. installed an oil cooler and problem solved.

no idea how different the demands are on the N/A donks with SOHC heads though.
vicious_fishes is offline   Reply With Quote
Old 11-15-2013, 11:42 PM   #16
mboulton
Scooby Newbie
 
Member#: 174433
Join Date: Mar 2008
Default

Ok. I have a GR with sensors on the head and block galleys because Chris mentioned this stuff previously. Yet I cannot get such a pronounced drop under various conditions.


Not sure I am a believer.


Please reply with the exact testing conditions so I can try to reproduce it. I have rapidly responding sensors but have not seen anything widely close to what you demonstrate on the video.


Not dismissing, just doubting the conclusion.

Mel
mboulton is offline   Reply With Quote
Old 11-16-2013, 12:09 AM   #17
Th3Franz
Scooby Specialist
 
Member#: 37146
Join Date: May 2003
Chapter/Region: MWSOC
Location: CA
Vehicle:
2005 Legacy GT
Stage tree fitty

Default

It sounds like this thread is misleading. It appears it should instead be titled:
"Why you shouldn't put a GD (10mm) oil pump in a GR (11mm) engine."

Also, correct me if I am wrong, but won't it only bypass if the pressure is higher? How is only 30% more flow a bad thing? And why do some well-known engine builders recommend a 11mm oil pump in a GD engine?
Th3Franz is offline   Reply With Quote
Old 11-16-2013, 02:03 AM   #18
subi400
Scooby Specialist
 
Member#: 216984
Join Date: Jul 2009
Chapter/Region: NWIC
Location: Coeur D Alene, ID
Vehicle:
1996 Impreza outback
Green

Default

Quote:
Originally Posted by Th3Franz View Post
It sounds like this thread is misleading. It appears it should instead be titled:
"Why you shouldn't put a GD (10mm) oil pump in a GR (11mm) engine."

Also, correct me if I am wrong, but won't it only bypass if the pressure is higher? How is only 30% more flow a bad thing? And why do some well-known engine builders recommend a 11mm oil pump in a GD engine?
That is because these so called engine builders don't understand that if they want more oil to the bearings and such that the bearing clearances need to be opened up some to allow the full flow from the pump to reach the bearings, allowing a stronger film of oil and effectively removing more heat. There won't be more flow or pressure to the heads because only so much can go to the heads. 30% more flow is bad when the engine doesn't need it that's why. I have seen hybrid builds revving to 9k with a 10mm oil pump with plenty of flow and pressure and they run great. Now explain that. Since that is the case, then why would they need a 11mm pump?

The argument that "hey look the oil pressure isn't that high as rpms go up" with a larger pump, but that doesn't fly..., because the extra flow and pressure is going through the bypass.

For reference, I was seeing 97 psi at 6-6.5k rpms on my 2.5 na engine with 2.2 heads and hla's with a new wrx 10mm oil pump with 2 stock shims. Mains were around 0.0024 on a cold block and around 0.002 for rods. Going a bit tighter this time around.

So, how in the world does a 02-05 wrx owner need more oil pressure and flow or a hybrid owner either stock redline or higher need much more flow or pressure when the 10mm pump puts out plenty? Even the 04-07 sti has a 10mm oil pump. So this issue really is quite simple, but people don't want to learn about what is TRUE, or simple just want to use something because they have the idea stuck in their head.

There was a known guy on here running a 11mm pump and they had 70 psi or so at 7 or 8k rpms. The pressure should of been at least 90+ psi. I believe this person was experimenting with the 11mm pump to see what it would do.

There are a lot of opinions out there and very few people that understand what is and what isn't. KillerBmotorsport is one of those few people that understands it.

Last edited by subi400; 11-16-2013 at 02:27 AM.
subi400 is offline   Reply With Quote
Old 11-16-2013, 09:36 AM   #19
mboulton
Scooby Newbie
 
Member#: 174433
Join Date: Mar 2008
Default

I understand fully the concept. I simply have not been able to reproduce the drop in pressure as the avcs changes intake and/or exhaust timing. Because Chris has mentioned this before, I set out to experiment and investigate this. Hence why I am requesting the conditions of testing so that I can try to replicate. I do have a P&L modified 11 pump however, and a custom Cobb tune that won't allow me to look at the AVCS tables. It is possible that my tuner has limited the amount of advance or retard thereby not 'demanding' so much oil diversion and hence the lack of a measurable drop.


Once I have a better explanation of the testing conditions I will try again and report. I will try to log rpm/load/oil pressure/and avcs simultaneously. That should help with understanding.


Mel
mboulton is offline   Reply With Quote
Old 11-16-2013, 05:51 PM   #20
lee586
Scooby Newbie
 
Member#: 212926
Join Date: Jun 2009
Location: Sydney, Austrailia
Vehicle:
97 Wrx
Black

Default

Quote:
Originally Posted by subydude View Post
That's not a pump issue, that's a gauge sender issue. You likely have a wire grounding out, or a sender that's having issues. Oil would not fluctuate like that at constant low revs.

The only other issue MIGHT be the by-pass valve sticking closed in the pump, but that seems rather unlikely.
I agree, I had sender issue like this to.
lee586 is offline   Reply With Quote
Old 11-16-2013, 11:40 PM   #21
mboulton
Scooby Newbie
 
Member#: 174433
Join Date: Mar 2008
Default

Okay. Eyeballing my gauges at about 2000 rpm in 3rd gear, if I let off the gas from a cruise situation the exhaust AVCS drops from 24 degrees to 0. The head oil pressure drops from around 50 to maybe 10 in a flash and then almost instantaneously rebounds back to 50. The block oil pressure measured at the rear right galley does not change at all. The head oil pressure appears to parallel the very fast AVCS timing changes.


I will try to get a video of it, and perhaps a true data log.

Mel
mboulton is offline   Reply With Quote
Old 11-17-2013, 11:01 AM   #22
KillerBMotorsport
NASIOC Vendor
 
Member#: 198281
Join Date: Dec 2008
Chapter/Region: MAIC
Location: Virginia
Vehicle:
2005 WRX/STi
WRB of course

Default

Quote:
Originally Posted by dstroy View Post
Yeah it sounds scary, but it really isn't, and it doesn't drop the instant you lift. You have to lift and engine brake for a while. Even then, the load on the engine is very low, it's spinning fast but there isn't nearly as much bearing load so you don't need the pressure that you would if you were WOT. When the exhaust side fully retards it helps slow the car down faster. 30% more oil flow makes up for the pressure drop.
The video isn't meant to scare people and you're absolutely right. The flow compensates for the AVCS demand, which is exactly why these pumps belong on GRs.

Quote:
Originally Posted by mboulton View Post
Please reply with the exact testing conditions so I can try to reproduce it. I have rapidly responding sensors but have not seen anything widely close to what you demonstrate on the video.

Not dismissing, just doubting the conclusion.

Mel
Low speed cruise, 4th gear. There are pressure drops like this all over the RPM/load range, but under these particular conditions the drop is near its highest.

Quote:
Originally Posted by subi400 View Post
That is because these so called engine builders don't understand that if they want more oil to the bearings and such that the bearing clearances need to be opened up some to allow the full flow from the pump to reach the bearings, allowing a stronger film of oil and effectively removing more heat. There won't be more flow or pressure to the heads because only so much can go to the heads. 30% more flow is bad when the engine doesn't need it that's why. I have seen hybrid builds revving to 9k with a 10mm oil pump with plenty of flow and pressure and they run great. Now explain that. Since that is the case, then why would they need a 11mm pump?

The argument that "hey look the oil pressure isn't that high as rpms go up" with a larger pump, but that doesn't fly..., because the extra flow and pressure is going through the bypass.

For reference, I was seeing 97 psi at 6-6.5k rpms on my 2.5 na engine with 2.2 heads and hla's with a new wrx 10mm oil pump with 2 stock shims. Mains were around 0.0024 on a cold block and around 0.002 for rods. Going a bit tighter this time around.

So, how in the world does a 02-05 wrx owner need more oil pressure and flow or a hybrid owner either stock redline or higher need much more flow or pressure when the 10mm pump puts out plenty? Even the 04-07 sti has a 10mm oil pump. So this issue really is quite simple, but people don't want to learn about what is TRUE, or simple just want to use something because they have the idea stuck in their head.

There was a known guy on here running a 11mm pump and they had 70 psi or so at 7 or 8k rpms. The pressure should of been at least 90+ psi. I believe this person was experimenting with the 11mm pump to see what it would do.

There are a lot of opinions out there and very few people that understand what is and what isn't. KillerBmotorsport is one of those few people that understands it.
Well said and sadly too true. If you're shopping for a builder and they include an 11mm pump on GD builds, ask why. If they give you the 'bigger is better' routine (with clearances opened up less than .002), or can't tell you why you need+30% more flow, or can't tell you what the different flow rates/pressure ratings are for pumps the different pumps then look for another builder.

Quote:
Originally Posted by Th3Franz View Post
It sounds like this thread is misleading. It appears it should instead be titled:
"Why you shouldn't put a GD (10mm) oil pump in a GR (11mm) engine."

Also, correct me if I am wrong, but won't it only bypass if the pressure is higher? How is only 30% more flow a bad thing? And why do some well-known engine builders recommend a 11mm oil pump in a GD engine?
Maybe the title should be changed?

The 30% more flow isn't going into the engine, it's going through the bypass and recirculating immediately back into the pump. Everytime oil is squeezed through those pump gears it adds heat so the less you can recirculate over and over and over, the better. The bypass also has poor flow characteristics and if you push enough through it, will aerate causing a pressure drop. Cold pressure can max the bypass causing seals to leak and/or overwhelm the turbo seals causing smoking (this is fairly well documented).

Quote:
Originally Posted by mboulton View Post
I understand fully the concept. I simply have not been able to reproduce the drop in pressure as the avcs changes intake and/or exhaust timing. Because Chris has mentioned this before, I set out to experiment and investigate this. Hence why I am requesting the conditions of testing so that I can try to replicate. I do have a P&L modified 11 pump however, and a custom Cobb tune that won't allow me to look at the AVCS tables. It is possible that my tuner has limited the amount of advance or retard thereby not 'demanding' so much oil diversion and hence the lack of a measurable drop.

Once I have a better explanation of the testing conditions I will try again and report. I will try to log rpm/load/oil pressure/and avcs simultaneously. That should help with understanding.

Mel
Mel, low RPM low load. Lift and the pressure drops. I have no idea how your particular tune may effect these variables. The P&L pumps do not follow OEM specs so that will also effect your results. It is odd that you're only observing the pressure drop in one location. Are your sensors calibrated to the same specs. Can you log them, swap the locations, and exactly duplicate your logs?

Quote:
Originally Posted by lee586 View Post
I agree, I had sender issue like this to.
It's not a sender problem.

Quote:
Originally Posted by mboulton View Post
Okay. Eyeballing my gauges at about 2000 rpm in 3rd gear, if I let off the gas from a cruise situation the exhaust AVCS drops from 24 degrees to 0. The head oil pressure drops from around 50 to maybe 10 in a flash and then almost instantaneously rebounds back to 50. The block oil pressure measured at the rear right galley does not change at all. The head oil pressure appears to parallel the very fast AVCS timing changes.

I will try to get a video of it, and perhaps a true data log.

Mel
When you lift it should drop and when you put any throttle back in it should recover. Basically following the cam timing, as designed
KillerBMotorsport is offline   Reply With Quote
Old 11-17-2013, 11:38 AM   #23
sidewayz
Scooby Specialist
 
Member#: 5810
Join Date: Apr 2001
Chapter/Region: Tri-State
Location: Easton PA
Vehicle:
2001 S366 2.5RS

Default

So it has nothing to do with the garbage sensors stri uses?
sidewayz is offline   Reply With Quote
Old 11-17-2013, 11:50 AM   #24
Irv Weissmanhowerton
Scooby Specialist
 
Member#: 278519
Join Date: Apr 2011
Chapter/Region: SCIC
Location: Phatbotti
Vehicle:
30r E85 sti 450+whp
kb'izzle

Default

You might not always "need" an 11mm oil pump on a gd. But are you saying that it actually hurts something?

I know there are endless people who could chime in with no problems at all like your experiencing. Sounds like just one instance your dealing with, if soooo many equally experienced tuners & builders have done the 11 in a gd in the past, I personally have had my last 4-5 motors with 11mm, My most current motor being built by Mike Keegan, who went over the parts list with me & assured all good, no problems, he was part of building ali/esx 1400whp 7 second car's motor

I'm sure alot of people will question this thread & take your input personally as most of us has had other reputable people tell us, 11 is all good, I have always understood 12 was overkill & out of the question, but 11 being bad on a single avcs or causing any issues, not so sure

Last edited by Irv Weissmanhowerton; 11-17-2013 at 12:28 PM.
Irv Weissmanhowerton is offline   Reply With Quote
Old 11-17-2013, 01:55 PM   #25
Th3Franz
Scooby Specialist
 
Member#: 37146
Join Date: May 2003
Chapter/Region: MWSOC
Location: CA
Vehicle:
2005 Legacy GT
Stage tree fitty

Default

What are the stock bearing clearances? How much do the bearing clearances need to be opened up to warrant an 11mm pump on a GD block? -- I saw mention of .002". I have a blueprinted engine so I'd like to take a closer look at this.
How much oil pressure when the engine is cold is too much for the bypass to handle?
Th3Franz 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

All times are GMT -4. The time now is 09:56 PM.


Powered by vBulletin® Version 3.7.0
Copyright ©2000 - 2020, Jelsoft Enterprises Ltd.
Powered by Searchlight © 2020 Axivo Inc.
Copyright ©1999 - 2019, North American Subaru Impreza Owners Club, Inc.

As an Amazon Associate I earn from qualifying purchases.