Intake Manifold Flow Database

ASF Machine · 08-19-2011, 10:04 PM

Here's what we tested:
Stock 07 STI
Sheet Metal V1 (I was told this was a Magnus V1 but Magnus never replied to my photo and email)
EJ25 SOHC Big Plenum Short Runner
EJ25 SOHC Big Plenum Long Runner
EJ25 SOHC Big Plenum Long Runner Modified For Reversed Setup
Forsa "Rear Entry" Manifold
Cosworth Cast Intake Manifold
EJ25 SOHC Big Plenum Short Runner ASF Porting Stage 0.5
Plastic not quite so fantastic Manifold
EJ25 SOHC Bigger Plenum Monstrosity with ASF Porting & 75mm TB

Procedure & Equipment: Superflow SF-110, tested @ 7" and corrected to 28", 4" Plexiglas bore fixture with small Plexi sheet adapter sealed to the fixture with an OE Subaru steel & rubber o ring intake gasket. Holes, non tested runners and nipples plugged with rubber plugs, tape and modeling clay. Tested with no velocity stack or throttle body; ie: open throttle flange. Stock STI , Magnus Sheet Metal & Cosworth used a topfeed TGV delete, short runner NA used it's own injector riser and the Forsa is a one piece design.
All tests that were denoted as done with a throttle body were done with a 60mm DBW partially gutted and wired WOT.

Intake manifold, cylinder head intake runner & throttle body as a system test, here:
http://forums.nasioc.com/forums/show...&postcount=140

Code:

Stock 07 STI
Runner 1 284 CFM
Runner 2 280 CFM
Runner 3 280 CFM
Runner 4 274 CFM
Average 279.5 CFM
Runner to runner max variation 10 CFM or 3.6%

Code:

Stock 07 STI w/ TB
Runner 1 303 CFM
Runner 2 304 CFM
Runner 3 306 CFM
Runner 4 299 CFM
Average 303 CFM
Runner to runner max variation 10 CFM or 2.3%

Code:

Sheet Metal
Runner 1 314 CFM
Runner 2 301 CFM
Runner 3 264 CFM
Runner 4 273 CFM
Average 288 CFM
Runner to runner max variation 50 CFM or 16%

Code:

EJ25 SOHC Big Plenum Short Runner
Runner 1 306 CFM
Runner 2 303 CFM
Runner 3 303 CFM
Runner 4 306 CFM
Average 304.5 CFM
Runner to runner max variation 3 CFM or 1%

Code:

EJ25 SOHC Big Plenum Long Runner
Runner 1 304 CFM
Runner 2 304 CFM
Runner 3 304 CFM
Runner 4 300 CFM
Average 303 CFM
Runner to runner max variation 4 CFM or 1.4%

Code:

 Modified EJ25 SOHC Big Plenum Long Runner
 Runner 1 314 CFM
 Runner 2 303 CFM
 Runner 3 308 CFM
 Runner 4 314 CFM
 Average 309.75 CFM
 Runner to runner max variation 11 CFM or 3.5%

Code:

Forsa Industries Rear Entry Sheet Metal Manifold
 Runner 1 329 CFM
 Runner 2 326 CFM
 Runner 3 314 CFM
 Runner 4 295 CFM
 Average 316 CFM
 Runner to runner max variation 34 CFM or 10.3%
Notes: One piece runner (ie: no TGV). If there was a radius or pipe
 on the throttle body flange, the number 4 runner wouldn't
 lag behind the others in terms of flow; I tested this by
 simply holding my index finger next to & slightly below
 the throttle flange opening which raised this runner's
 flow to 317 CFM. The close proximity of this runner to
 the open throttle flange makes it a sharp bend.

Code:

Forsa Industries Rear Entry Sheet Metal Manifold with TB
Runner 1 352 CFM
Runner 2 343 CFM
Runner 3 324 CFM
Runner 4 324 CFM
Average 335.75 CFM
Runner to runner max variation 28 CFM or 8.3%
Notes: Having a throttle body did help flow variation here.
Runner 4 was EXTREMELY turbulent, as in turbulent enough
 to make the flow depression bounce 1".

Code:

Cosworth Cast Intake Manifold
 Runner 1 303 CFM
 Runner 2 299 CFM
 Runner 3 299 CFM
 Runner 4 314 CFM
 Average 303.75 CFM
 Runner to runner max variation 15 CFM or 4.8%

Code:

Cosworth Cast Intake Manifold with TB
 Runner 1 333 CFM
 Runner 2 318 CFM
 Runner 3 318 CFM
 Runner 4 314 CFM
 Average 320.75 CFM
 Runner to runner max variation 19 CFM or 5.9%
Notes: That is not a typo, runner 4 had no change between
 having a TB and not having one. Oddly, with a throttle body,
 flow variation actually went up

Code:

EJ25 SOHC Big Plenum Short Runner ASF Porting Stage 0.5
Runner 1 318 CFM
Runner 2 310 CFM
Runner 3 322 CFM
Runner 4 310 CFM
Average 315 CFM
Runner to runner max variation 12 CFM or 3.7%
Notes: Stage 0.5 consisted of upper runner to lower runner matching,
 partial runner flash removal and EGR pillar removal from the center-bottom
 of the plenum.

Code:

EJ25 SOHC Big Plenum Short Runner ASF Porting Stage 0.5 with TB
Runner 1 354 CFM
Runner 2 354 CFM
Runner 3 337 CFM
Runner 4 331 CFM
Average 344 CFM
Runner to runner max variation 23 CFM or 6.6%
Notes: Flow variation more than doubled with throttle body here.

Code:

Plastic Thing with TB
Runner 1 293 CFM
Runner 2 283 CFM
Runner 3 283 CFM
Runner 4 291 CFM
Average 287.5 CFM
Runner to runner max variation 10 CFM or 3.5%

Code:

EJ25 SOHC Big Modded Plenum Long Runner ASF Monstrosity with 75mm TB
Runner 1 376 CFM
Runner 2 362 CFM
Runner 3 396 CFM
Runner 4 389 CFM
Average 380.75 CFM
Runner to runner max variation 34 CFM or 8.9%
Notes: OMFG. Pic was during setup, so rest easy the
 brake booster nipple was plugged during testing.

Code:

Process West Holy Moly Thing of Beauty
Runner 1 349 CFM
Runner 2 356 CFM
Runner 3 360 CFM
Runner 4 374 CFM
Average 359.75 CFM
Runner to runner max variation 25 CFM or 6.9%
Notes: Large plenum and short runner characteristics 
cannot be seen in this test but my hypothesis is that 
this could be a candidate for best choice in a big 
turbo/big rpm setup.

Thanks to Tyler Williams the rainbow dude & Will @ Elevated Tuning and for their help and to Brian L (RexFTW) for the Process West, Zach (Fate066), Fin @ Forsa and Jordan (MartinSTi05) for the manifolds to test.

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fateo66 · 08-19-2011, 10:13 PM

I like what I see!

subiewhore · 08-19-2011, 10:16 PM

huh, I was wondering what happened to the intake manifold off my car!

ASF Machine · 08-19-2011, 10:25 PM

Plastic with TB

Short Runner NA with ASF Stage .5

Cossie with TB

Stock STI with TB

Forsa with TB

wrxsubiemod · 08-20-2011, 02:22 AM

I really appreciate you posting these test results. I have always been up in the air about switching to a oem sti manifold or 2.5rs mani. Now I'm just curious on what my ported 03 wrx manifold will flow to see if it would be worth it.

I have had my hands on plenty wrx and sti intake manifold and never really saw any differance besides tb bolt pattern and color.

methaddict · 08-20-2011, 02:29 AM

EJ25 SOHC Big Plenum Long Runner
Runner 1 304 CFM
Runner 2 304 CFM
Runner 3 304 CFM
Runner 4 300 CFM
Average 303 CFM
Runner to runner max variation 4 CFM

^This is what I'll be running.
Finally some numbers on a flow bench. The only other manifolds I'd like to see is the Cosworth and the vers 9 jdm long runner which would probably have the same results as any stock sti manifold.

FuJi K · 08-20-2011, 02:30 AM

....and I have the red one and the short SOHC one in my possession.

25rsti · 08-20-2011, 07:17 AM

Thanks for you contribution. I'm running the long runner sohc manifold and always heard about these characteristics, but never saw the data. Seeing the actual #s makes me feel much better.

Though I do wonder why the other sohc one flows more, the one with the custom change.

MartinSTi05 · 08-20-2011, 09:17 AM

I have a cosworth laying around. If I send it out do you want to test it?

maxpowr · 08-20-2011, 09:39 AM

what model year are theses from?

EJ25 SOHC Big Plenum Short Runner...96-2001?

ASF Machine · 08-20-2011, 10:05 AM

Martin, send it over and we'll test it.

Max, all of the big plenum SOHC are from newer EJ253s (think 06+), exact years and models I don't know, possibly someone (hey Zach) could chime in with more exact info.

We did this because all we ever heard was speculation without any real data, we didn't expect the big plenum NA manifolds to be so exceptional. We did hypothesize that they would have great runner to runner balance but we had figured they would only marginally outflow the STi and get destroyed by the SMIM. Testing revealed that the SMIM has poor balance, front runners (1&3) vs. back runners (2&4).
I am excited to test a Cossie as this will be great reference point when considering Cosworth's own flow numbers on the stocker when corrected from 50" (421 avg cfm) to 28"(315 avg cfm which is still 12% higher than our findings), the cast Cossie should make 350+ avg cfm on our bench corrected to 28" yet I am guessing somewhere closer to 315 avg cfm.

ASF Machine · 08-20-2011, 10:35 AM

Quote:

Originally Posted by 25rsti

Thanks for you contribution. I'm running the long runner sohc manifold and always heard about these characteristics, but never saw the data. Seeing the actual #s makes me feel much better.

Though I do wonder why the other sohc one flows more, the one with the custom change.

Zach modified the plenum on this one, he removed the pillar out of it and put a sloping roof on it in order to move the TB flange down for front entry.

The beauty part is that we think all the big plenum intakes have room for improvement.

axelthrasher · 08-20-2011, 11:10 AM

Awesome test, glad to finally see some numbers. I only wish you had a 1 piece V8 Spec C to test. I'm really curious as to what numbers you would get out of one of those.

Back Road Runner · 08-20-2011, 12:53 PM

Excellent work. This is one thing this site and the Subaru community has been lacking for a LONG time.

It's interesting to see the gross variation of the e-Bay cheapy.

I'm curious, there are quite a few other manifolds out there. Are you guys willing to test more manifolds if people sent them in to you? I'm just thinking of things like old cast versus new plastic NA manifolds, the very large diameter runner Legacy (GT?) manifold, the Cosworth high flow manifold, even some stock manifolds with some porting work (to see if this is worth it, although may be more beneficial attacked to a head and pulled though versus the manifold itself).

I would just love to see more comprehensive data for a lot of the major products out there.

maxpowr · 08-20-2011, 01:32 PM

i agree...the tech section here on nasioc is a little thin...

MartinSTi05 · 08-20-2011, 01:32 PM

I support a hard numbers style of testing. Many loud mouths are quick to condemn any product they don't have any real world experience with. Many think the cissies manifold kills low end etc etc. I sure had a healthy power curve with it, oh wait that's because the rest of my setup was thought out.

This type of testing eliminates many variables that cloud other conclusions people have made. That being said it would be nice to see dynamic testing that could quantify the effects of the runner length, ID, firing order and plenum volume. Maybe a "standard" test Subaru setup...

maxpowr · 08-20-2011, 01:38 PM

nasioc sponsored? ^^^

KenSekiguchi · 08-20-2011, 01:47 PM

Here's some additional CFM numbers for you guys. I had the OEM JDM V7 EJ207 STi Intake Manifold & TGV's sent out to Extrude Hone and they threw it up on the flow bench before and after the Extrude Hone process. Impressive CFM gains in my opinion considering the expensive aftermarket options that are available.

OEM JDM V7 EJ207 STi Intake Manifold & TGV's

SuperFlow 1020 Flow Bench @ 28"
Test Pressure @ 29.6 PSI
Temperature during Flow Bench Testing - +78*F

OEM JDM V7 STi EJ207 / After Extrude Hone process ( Difference in CFM from Stock to after Extrude Hone process - )

Runner #1 Before - 263.7 CFM / Runner #1 After - 311.8 CFM ( +48.1 CFM, 18.2% increase )

Runner #2 Before - 274.3 CFM / Runner #2 After - 316.4 CFM ( +42.1 CFM, 15.3% increase )

Runner #3 Before - 272.5 CFM / Runner #3 After - 316.0 CFM ( +43.5 CFM, 15.9% increase )

Runner #4 Before - 269.8 CFM / Runner #4 After - 314.9 CFM ( +45.1 CFM, 16.7% increase )

--
Ken Sekiguchi

Homemade WRX · 08-20-2011, 02:02 PM

Quote:

Originally Posted by MartinSTi05

I support a hard numbers style of testing. Many loud mouths are quick to condemn any product they don't have any real world experience with. Many think the cissies manifold kills low end etc etc. I sure had a healthy power curve with it, oh wait that's because the rest of my setup was thought out.

This type of testing eliminates many variables that cloud other conclusions people have made. That being said it would be nice to see dynamic testing that could quantify the effects of the runner length, ID, firing order and plenum volume. Maybe a "standard" test Subaru setup...

I just wish I had been able to get a flowbench that I was gonna get last fall. It was swiped from under my feet 1 day before I could pick it up

ASF Machine · 08-20-2011, 02:32 PM

I'd love to see what someone with access to CFD & wet flow could come up with.

That said, we're not super interested in testing someone's home ported stock WRX manifold and I wouldn't be super excited about even a JDM long runner (I'd probably still do one) as I think we'd find that it's awfully close to a USDM STI.

I have a plastic Leggy XT manifold somewhere that I wanna do and I'd like to maybe test a Cossie, Forsa, Corsa-Veloce, Tomei and maybe a Tomei knockoff.

ASF Machine · 08-20-2011, 02:36 PM

Quote:

Originally Posted by MartinSTi05

I support a hard numbers style of testing. Many loud mouths are quick to condemn any product they don't have any real world experience with. Many think the cissies manifold kills low end etc etc. I sure had a healthy power curve with it, oh wait that's because the rest of my setup was thought out.

This type of testing eliminates many variables that cloud other conclusions people have made. That being said it would be nice to see dynamic testing that could quantify the effects of the runner length, ID, firing order and plenum volume. Maybe a "standard" test Subaru setup...

I had ideas about building a throttle body flange adapter and flipping the switch on the machine to blow through it but there were two major issues with that plan: 1, no one else's numbers have been done that way and 2, we'd surely run out of capacity on our little machine. I thought it may be a better indicator on a forced induction setup but alas we stuck with the standard procedure.

Mister Tanker · 08-20-2011, 02:48 PM

Id like to see a test of a wrx manifold thats been port matched to the tgv's. I have ported a few of these manifolds and lots of material is removed in the process.

wrxsubiemod · 08-20-2011, 03:12 PM

^ I agree, but I really haven't seen a differance between sti and wrx manifolds. The test was performed with tgv deletes and sti mani so id assume a wrx manifold will be very close. I'm sure grimmspeed has some back up flow data from ported to non ported we can look at.

MartinSTi05 · 08-20-2011, 03:32 PM

Quote:

Originally Posted by ASF Machine

I had ideas about building a throttle body flange adapter and flipping the switch on the machine to blow through it but there were two major issues with that plan: 1, no one else's numbers have been done that way and 2, we'd surely run out of capacity on our little machine. I thought it may be a better indicator on a forced induction setup but alas we stuck with the standard procedure.

Unforunately we don't gave access to all the toys we can dream of as a community. However this is one hell of a good start.

subyswamper · 08-21-2011, 03:45 PM

I like this very much!!!! Special thanks to Zach and Margarite for giving up their intakes for testing.

08-20-2011, 10:05 AM	#11
ASF Machine Former Vendor Member#: 236349 Join Date: Jan 2010 Location: Western Colorado Vehicle: 1993 Impreza OD Green	Martin, send it over and we'll test it. Max, all of the big plenum SOHC are from newer EJ253s (think 06+), exact years and models I don't know, possibly someone (hey Zach) could chime in with more exact info. We did this because all we ever heard was speculation without any real data, we didn't expect the big plenum NA manifolds to be so exceptional. We did hypothesize that they would have great runner to runner balance but we had figured they would only marginally outflow the STi and get destroyed by the SMIM. Testing revealed that the SMIM has poor balance, front runners (1&3) vs. back runners (2&4). I am excited to test a Cossie as this will be great reference point when considering Cosworth's own flow numbers on the stocker when corrected from 50" (421 avg cfm) to 28"(315 avg cfm which is still 12% higher than our findings), the cast Cossie should make 350+ avg cfm on our bench corrected to 28" yet I am guessing somewhere closer to 315 avg cfm. Last edited by ASF Machine; 08-20-2011 at 10:31 AM.

08-20-2011, 02:32 PM	#20
ASF Machine Former Vendor Member#: 236349 Join Date: Jan 2010 Location: Western Colorado Vehicle: 1993 Impreza OD Green	I'd love to see what someone with access to CFD & wet flow could come up with. That said, we're not super interested in testing someone's home ported stock WRX manifold and I wouldn't be super excited about even a JDM long runner (I'd probably still do one) as I think we'd find that it's awfully close to a USDM STI. I have a plastic Leggy XT manifold somewhere that I wanna do and I'd like to maybe test a Cossie, Forsa, Corsa-Veloce, Tomei and maybe a Tomei knockoff. Last edited by ASF Machine; 08-20-2011 at 02:37 PM.

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08-19-2011, 10:13 PM	#2
fateo66 Scooby Specialist Member#: 130997 Join Date: Nov 2006 Location: Denver, Co.	I like what I see!

08-19-2011, 10:16 PM	#3
subiewhore Scooby Newbie Member#: 138786 Join Date: Jan 2007 Chapter/Region: RMIC Location: subaruville, CO Vehicle: 05 obp wrs ^.- rally time	huh, I was wondering what happened to the intake manifold off my car!

08-19-2011, 10:25 PM	#4
ASF Machine Former Vendor Member#: 236349 Join Date: Jan 2010 Location: Western Colorado Vehicle: 1993 Impreza OD Green	Plastic with TB Short Runner NA with ASF Stage .5 Cossie with TB Stock STI with TB Forsa with TB Last edited by ASF Machine; 01-13-2012 at 01:38 PM.

08-20-2011, 02:22 AM	#5
wrxsubiemod Scooby Specialist Member#: 165104 Join Date: Nov 2007 Chapter/Region: SCIC Location: Riverside CA Vehicle: E85 SoCalPorting Owner	I really appreciate you posting these test results. I have always been up in the air about switching to a oem sti manifold or 2.5rs mani. Now I'm just curious on what my ported 03 wrx manifold will flow to see if it would be worth it. I have had my hands on plenty wrx and sti intake manifold and never really saw any differance besides tb bolt pattern and color.

08-20-2011, 02:29 AM	#6
methaddict Scooby Specialist Member#: 159738 Join Date: Sep 2007 Chapter/Region: SCIC Location: SGV Vehicle: 2004 WRB STi 620awhp OFCD V3, FR TS, BW8374EFR	EJ25 SOHC Big Plenum Long Runner Runner 1 304 CFM Runner 2 304 CFM Runner 3 304 CFM Runner 4 300 CFM Average 303 CFM Runner to runner max variation 4 CFM ^This is what I'll be running. Finally some numbers on a flow bench. The only other manifolds I'd like to see is the Cosworth and the vers 9 jdm long runner which would probably have the same results as any stock sti manifold.

08-20-2011, 02:30 AM	#7
FuJi K Scooby Guru Member#: 3687 Join Date: Jan 2001 Chapter/Region: MWSOC Location: St. Paul, MN Vehicle: MY99 GF4 JDM 6spd	....and I have the red one and the short SOHC one in my possession.

08-20-2011, 07:17 AM	#8
25rsti Scooby Guru Member#: 166324 Join Date: Dec 2007 Chapter/Region: NESIC Location: BLOD in BLOD out	Thanks for you contribution. I'm running the long runner sohc manifold and always heard about these characteristics, but never saw the data. Seeing the actual #s makes me feel much better. Though I do wonder why the other sohc one flows more, the one with the custom change.

08-20-2011, 09:17 AM	#9
MartinSTi05 Scooby Specialist Member#: 145145 Join Date: Apr 2007 Chapter/Region: MWSOC Location: Rockford, Il Vehicle: 2006 wrx STi	I have a cosworth laying around. If I send it out do you want to test it?

08-20-2011, 09:39 AM	#10
maxpowr Scooby Guru Member#: 159243 Join Date: Sep 2007 Chapter/Region: Tri-State Location: medford nj 08055 Vehicle: 5/01 bugeye Hakt Ecu is back!	what model year are theses from? EJ25 SOHC Big Plenum Short Runner...96-2001?

08-20-2011, 11:10 AM	#13
axelthrasher Scooby Guru Member#: 144779 Join Date: Mar 2007 Chapter/Region: MWSOC Location: In the land up over Vehicle: 200X ZOMG a car 100% crabon fibre girlfrendorz	Awesome test, glad to finally see some numbers. I only wish you had a 1 piece V8 Spec C to test. I'm really curious as to what numbers you would get out of one of those.

08-20-2011, 12:53 PM	#14
Back Road Runner Scooby Guru Member#: 60082 Join Date: Apr 2004 Chapter/Region: MWSOC Location: Minnesota Vehicle: 2004 Forester STI Silver	Excellent work. This is one thing this site and the Subaru community has been lacking for a LONG time. It's interesting to see the gross variation of the e-Bay cheapy. I'm curious, there are quite a few other manifolds out there. Are you guys willing to test more manifolds if people sent them in to you? I'm just thinking of things like old cast versus new plastic NA manifolds, the very large diameter runner Legacy (GT?) manifold, the Cosworth high flow manifold, even some stock manifolds with some porting work (to see if this is worth it, although may be more beneficial attacked to a head and pulled though versus the manifold itself). I would just love to see more comprehensive data for a lot of the major products out there.

08-20-2011, 01:32 PM	#15
maxpowr Scooby Guru Member#: 159243 Join Date: Sep 2007 Chapter/Region: Tri-State Location: medford nj 08055 Vehicle: 5/01 bugeye Hakt Ecu is back!	i agree...the tech section here on nasioc is a little thin...

08-20-2011, 01:38 PM	#17
maxpowr Scooby Guru Member#: 159243 Join Date: Sep 2007 Chapter/Region: Tri-State Location: medford nj 08055 Vehicle: 5/01 bugeye Hakt Ecu is back!	nasioc sponsored? ^^^

08-20-2011, 01:47 PM	#18
KenSekiguchi Scooby Specialist Member#: 175331 Join Date: Mar 2008 Chapter/Region: MWSOC Location: Rolling Meadows, IL Vehicle: 2002 WRX STi - WRB JDM V7 EJ207/13' Felt Z85	Here's some additional CFM numbers for you guys. I had the OEM JDM V7 EJ207 STi Intake Manifold & TGV's sent out to Extrude Hone and they threw it up on the flow bench before and after the Extrude Hone process. Impressive CFM gains in my opinion considering the expensive aftermarket options that are available. OEM JDM V7 EJ207 STi Intake Manifold & TGV's SuperFlow 1020 Flow Bench @ 28" Test Pressure @ 29.6 PSI Temperature during Flow Bench Testing - +78*F OEM JDM V7 STi EJ207 / After Extrude Hone process ( Difference in CFM from Stock to after Extrude Hone process - ) Runner #1 Before - 263.7 CFM / Runner #1 After - 311.8 CFM ( +48.1 CFM, 18.2% increase ) Runner #2 Before - 274.3 CFM / Runner #2 After - 316.4 CFM ( +42.1 CFM, 15.3% increase ) Runner #3 Before - 272.5 CFM / Runner #3 After - 316.0 CFM ( +43.5 CFM, 15.9% increase ) Runner #4 Before - 269.8 CFM / Runner #4 After - 314.9 CFM ( +45.1 CFM, 16.7% increase ) -- Ken Sekiguchi

08-20-2011, 02:48 PM	#22
Mister Tanker Scooby Specialist Member#: 237759 Join Date: Feb 2010 Chapter/Region: TXIC Location: Houston Vehicle: 2003 WRX Wagon Built ej205 478whp 417wtq	Id like to see a test of a wrx manifold thats been port matched to the tgv's. I have ported a few of these manifolds and lots of material is removed in the process.

08-20-2011, 03:12 PM	#23
wrxsubiemod Scooby Specialist Member#: 165104 Join Date: Nov 2007 Chapter/Region: SCIC Location: Riverside CA Vehicle: E85 SoCalPorting Owner	^ I agree, but I really haven't seen a differance between sti and wrx manifolds. The test was performed with tgv deletes and sti mani so id assume a wrx manifold will be very close. I'm sure grimmspeed has some back up flow data from ported to non ported we can look at.

08-21-2011, 03:45 PM	#25
subyswamper Scooby Newbie Member#: 91049 Join Date: Jul 2005 Chapter/Region: RMIC Location: WheatRidge,Colorado Vehicle: 2008 wrx wgn charcoal grey	I like this very much!!!! Special thanks to Zach and Margarite for giving up their intakes for testing.