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CovertRussian's 05 LGT Build Thread


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In my head the picture of your garage looks like an automotive smorgasbord with rows and rows of shelving filled with a ginormous collection of spare parts, filters, hoses, sensors...

If reality is any different than that don't tell me otherwise, I prefer thinking of your work space as somewhere the mythbusters would visit if they ever got in a pinch.

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Covert, what's are your airflow numbers for those test in G/Sec?

 

This is the granular flow-vs-depresion results Jeff (myaudis4.com guy) got on our stock intake:

restriction.PNG.b71c55e568c5149b3f7b4aad89da2af1.PNG

 

335cfm is roughly what our cars will do stock. So it looks like your improved intake brings performance back inline with what Subaru was designing toward. Does your setup have room to run one of the 8-10" long fiters that the AEM Intakes for the '08+ WRX/STI used?

 

Also curious that the turbo drive energy reduction due to a ~0.75PSI depression reduction didn't show any power gains. But you also reduced backpressure by a lot in previous test showing little to no gain.

Edited by utc_pyro
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I'll post some back to back results tonight with airflow numbers. I don't think we can trust the g/sec numbers at the core value though (since even me using a stock MAF housing in different configuration) required a 20% MAF Scale increase.

 

The Amsoil 6" wide filter (EAAU6065) is 6.5" long, which is longer then the other two that I tested and yet it was still higher (though filter quality is at play here).

 

Also curious that the turbo drive energy reduction due to a ~0.75PSI depression reduction didn't show any power gains. But you also reduced backpressure by a lot in previous test showing little to no gain.

 

It also translates to manifold boost increase by 0.75psi on my wastegate only setup. While at 24F I saw no real gains (nothing that I couldn't call within margin of error). At 50F I saw a definite increase up top, which is where I would expect an intake to help the most. I'll have that data & graphs posted later tonight too :)

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I've been dancing around intakes for years now:

Part 1: Building a Custom 3" WAI Intake

Part 2: Turning WAI into CAI

 

In the end I would always go back to the stock intake, mainly because the WAI was too hot, and CAI would get wet during the rain. But after seeing how the CAI is half as restrictive as the stock airbox figured I would give it another go.

 

To fix the rain issue I had to raise the filter to sit much higher.

http://legacygt.com/forums/attachment.php?attachmentid=262875&stc=1&d=1520485506

 

It's sitting right under the frame

http://legacygt.com/forums/attachment.php?attachmentid=262876&stc=1&d=1520485506

 

With filter sitting higher this yellow (safety related) wire becomes a concern. I had cut and adjust the intake a bunch to make sure it would not rub against it.

http://legacygt.com/forums/attachment.php?attachmentid=262877&stc=1&d=1520485506

 

Testing

While at 25F there wasn't really a measurable gain, at 50F there was a significant gain above 5k RPM, at first I thought it was a fluke but doing a couple more pulls showed the same trends. Also I did these pulls within 30 min of each other.

http://legacygt.com/forums/attachment.php?attachmentid=262882&stc=1&d=1520485506

 

Ignition Timing

Past experience showed that the intake wants 1-2* less timing overall. The CAI run actually knocked at ~6.1k and retarted 1* of timing. I reduced the timing by 2* and there was a little bit of power loss down low, but up top stayed the same. Thus I believe optimal timing is -1* vs stock intake.

 

Intake Air Temps

Were just about identical, this time around I have post IC numbers too!

http://legacygt.com/forums/attachment.php?attachmentid=262881&stc=1&d=1520485506

 

While standing still the IAT's do creep up faster and higher then with the stock intake, but once you start moving the CAI will shed the heat much faster then stock. It also is closer to ambient while driving, usually about 1-3F higher, while stock intake would be 3-10F higher.

 

I think a proper heatshield would help reduce the engine bay heat bleed over.

 

Spool Time

Did you notice that the turbo spool time decreased? Peak boost comes on about 200rpm sooner. What's odd is, looking at my older logs and stock intake spool matches the faster spool of the CAI. This is why I try to test mods side by side nowdays, even with all of the corrections, day to day differences can still change how the car does.

 

Response

Another non-measurable benefit is increased engine response, this was especially noticeable after I reinstalled the stock airbox, the car just become lazier, like something is holding it back during partial throttle accelerations.

 

Engine Load & Mass Airflow

Normally I increase MAF scales by 25%, which would result in higher engine loads. This time I wanted to keep the engine loads about the same so increased the MAF by 20%. This seems to have gotten the scales to be right on par with the stock ones, though I'm not sure that is technically accurate since the intake is sucking in more air and did raise the boost levels.

 

http://legacygt.com/forums/attachment.php?attachmentid=262878&stc=1&d=1520485506

 

Mass Airflow as expected is identical due to 20% increase being 1:1 to stock intake.

http://legacygt.com/forums/attachment.php?attachmentid=262880&stc=1&d=1520485506

 

MAF Voltage:

Finally the MAF voltage, once again using the stock MAF housing but a less restrictive entry majorly reduces the MAF voltage.

http://legacygt.com/forums/attachment.php?attachmentid=262879&stc=1&d=1520485506

 

Fuel Economy

I saw a pretty substantial highway MPG increase again, went from 27.96mpg to 29.67mpg totaling a 1.71mpg gain highway.

 

This jives with what I've seen in previous stock vs CAI MPG gains. I think this is due to to the intake causing the car to be more powerful reducing the amount of time needing accelerate to keep the car at speed.

 

What's interesting about this is, most of the intake depression comes at full throttle almost redline operation. Highway driving is at ~2.8k rpm, and partial throttle, in theory there should be no intake depression even on the stock intake. Thus I am a little baffled as to why it instantly gains 1+ MPG everytime I install it.

 

Conclusion

This version of the CAI is finally a winning combination. It's not super sensitive to rain but it also is good at shedding heat, plus increased response and MPG improvement is a great benefit on it's own even without the decent power bump.

1631141653_CustomCAIv2_002.thumb.jpg.1d46dc0181f917e0a0ccdd54661f6955.jpg

1216627842_CustomCAIv2_003.thumb.jpg.472ecb188b37e36a0d0d84254ca93e12.jpg

902354670_CustomCAIv2_004.jpg.838e09521399e427908a883076f05d95.jpg

1658222385_EngineLoad-StockvsCAI20MAF.png.e3110d4f2dfd0228c601db2fce5c1417.png

1398620834_MAFV-StockvsCAI20MAF.png.de5e2fa882fd053aeb438a4730ac59bb.png

1216490413_MassAirflow-StockvsCAI20MAF.png.733e50b2a45295bb148aaeadeff91880.png

1834339272_PostICIAT-StockvsCAI20MAF.png.523893bf4ba6b33455d54b744bfdac8a.png

77929799_Dyno-StockIntakevsCustom3inCAI.thumb.png.6bf4d9b599168e7c6236a70ab2063154.png

Edited by covertrussian

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In the CAI post I mentioned how I simply increased the MAF by 20% and did the power tests without doing anything else. Well usually I run 25% more, and that would require a bit more tuning to get it right. I wanted to see what exactly changed so did some testing tonight.

 

MAF Voltage was identical, as you would hope.

http://legacygt.com/forums/attachment.php?attachmentid=262901&stc=1&d=1520572476

 

Mass Airflow is up by about ~12 g/s at peak

http://legacygt.com/forums/attachment.php?attachmentid=262900&stc=1&d=1520572476

 

Engine Load is is up by ~14g/rev

http://legacygt.com/forums/attachment.php?attachmentid=262902&stc=1&d=1520572476

 

Since g/rev is higher you should expect the AFR's to be slighter richer, but the biggest change will come from the Primary Open Loop table carrying more weight. In this case fuel was 4.6% overall richer, which is about 0.5AFR richer.

http://legacygt.com/forums/attachment.php?attachmentid=262903&d=1520572647

 

Since each fuel cell in the open loop table now adding more fuel per cell value, I needed to increase the open loop portions of the map by 4.6%. This makes the cell values be higher, which means leaner.

http://legacygt.com/forums/attachment.php?attachmentid=262907&stc=1&d=1520601760

 

 

Final comparison is of the AF 1 Learning, I've been chasing a vacuum leak with the stock intake, but I'm not sure I actually have one anymore. Stock intake has +9-12% learning for A column. +20% has about +1%, and +25% has about -4% learning. Both CAI MAF scales are more true to real world values, which can be seen by less fuel having to be added or removed.

http://legacygt.com/forums/attachment.php?attachmentid=262905&stc=1&d=1520572476

 

This is one of those times that you have to remember that the stock MAF scales are meant for stock setups and tunes, which is why they vary even form year to year. Even changing engine airflow without changing the intake (ie: AVCS, turbo, header, exhaust), can effect how accurate your MAF scale is.

157082785_MassAirflow.png.4e97dca3269f70b97670a839fd335d85.png

838671743_MAFV.png.df825d5607ac6276c071b9d9d879d692.png

1426572621_EngineLoad.png.071a03078a3dfba29c99edbb20225fc9.png

AFR.png.7836af0a2d2042ebf5a59db9e1090305.png

325900653_0303-01_50f_1hidle_Backroads.png.dd4f8a420366a16417c2650ef1c20167.png

110018854_FuelMapAdjustment.PNG.987fe792f1e175ab29318669ed7efe8d.PNG

Edited by covertrussian

05 LGT 16G 14psi 290whp/30mpg (SOLD)

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  • 1 month later...

Continuation of Intake Depression (Vacuum) Testing...

 

My Perrin STI inlet has had a hole in it since day one, I patched it up with silicon wrap and tape, but looks like after 5 years of heat cycles make the tape and silicon wrap come off.

 

http://legacygt.com/forums/attachment.php?attachmentid=263924&stc=1&d=1523334601

 

Since there was a big hole already, I figured I would use it to my advantage. It allowed me to test the intake depression pretty darn close to the turbo, which would give us the Total Pressure Drop that the turbo sees.

http://legacygt.com/forums/attachment.php?attachmentid=263925&stc=1&d=1523334601

 

From there I threw the hose up and connected it to the rest of the testing rig.

http://legacygt.com/forums/attachment.php?attachmentid=263926&stc=1&d=1523334601

 

I then did a couple redline pulls to get base lines, and then went to the same exact road as before and did a final pull. Manometer registered -42.27 inches of water column (inH2O) with my custom cold air intake.

http://legacygt.com/forums/attachment.php?attachmentid=263927&stc=1&d=1523334601

 

If you don't remember, that custom CAI measured -21.32 inH2O at the beginning of the inlet and stock intake system measured -44.55 inH2O. But, those measurements don't include the pressure drop of the inlet itself, only the intake piping, MAF, and Filter media.

 

If we subtrack the -21.32 inH2O that the CAI pressure drops from the total pressure drop, -42.27 inH2O, we get -20.93 inH2O between the turbo and intake. To explain it in layman's terms, the section of piping between the two red lines pressure drops almost as much as the whole stock intake assembly!

http://legacygt.com/forums/attachment.php?attachmentid=263928&stc=1&d=1523334601

 

We can also now calculate the total pressure drop with stock airbox. By adding the inlet pressure drop to the stock intake pressure drop. In this case we get a total intake pressure drop at a massive -65.48 inH2O, that's 4.81 inHg or 2.3psi worth of vacuum that raises your turbo's pressure ratio and forces it to overspin to deliver desired boost levels.

 

Now I'm curious on how much the stock inlet would pressure drop, unfortunately my spare OEM one was destroyed by a local friend trying to test fit it. Maybe I can fix my stock one enough to do a few pulls.

 

This also brings to an interesting conundrum: with such high pre-turbo vacuum levels, having a big vacuum leak would actually improve performance because it would reduce the amount of vacuum that the turbo has to overcome :lol:.

PerrinInlet_HoleFixing.thumb.JPG.037d534f61db2998abfc6111be04be64.JPG

PerrinSTI_Inlet_PD001.jpg.14c5eeea1b34da6f2956a9c3263663e1.jpg

PerrinSTI_Inlet_PD002.jpg.540db2d8130ba43b4b42a2a0b99378f8.jpg

PerrinSTI_Inlet_PD003.thumb.jpg.e48e6a284e64bec34c5121c08a8449d9.jpg

PerrinSTI_Inlet_PD004.jpg.622743e788930658849300b5e3e07545.jpg

Edited by covertrussian

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Due to Bernoulli’s principal you may just be seeing the effect of the air flow speed. What’s your G/sec reading at this pressure? You should be able to compute the air velocity at your test point and see how much pressure drop to expect in an ideal situation.

 

That said i wonder about the 2.4-2.5” turbo inlets and if ones like the AVO or COBB with a 3” inlet gradually reducing to 2.4” at the turbo might perform better.

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Due to Bernoulli’s principal you may just be seeing the effect of the air flow speed. What’s your G/sec reading at this pressure? You should be able to compute the air velocity at your test point and see how much pressure drop to expect in an ideal situation.

 

Ah interesting, but I would expect it to keep up couple inches away too. I'll take look at the logs and see. I don't think we can trust Subaru's g/sec calculations though, they are arbitrary :lol:

 

That said i wonder about the 2.4-2.5” turbo inlets and if ones like the AVO or COBB with a 3” inlet gradually reducing to 2.4” at the turbo might perform better.

 

I've been wanting to build a custom 3" inlet anyway. Since I had the manifold off for another issue, I test fitted it this weekend. I need to figure out a way to add a BOV port, and one 5/8" breather port still.

 

WARNING this picture contains spoilers of what's to come in next couple weeks....

http://legacygt.com/forums/attachment.php?attachmentid=263933&stc=1&d=1523372685

20180408_190413.thumb.jpg.3ef57b5fbdc312d55eaf3ea9a65c9c35.jpg

05 LGT 16G 14psi 290whp/30mpg (SOLD)

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Taking it off took about 1.5 hours. Test fitting certain intake restrictive devices and reporting them took another 2 hours, then another 2 hours to reinstall. Whole ordeal took about 6 hours with pictures and all.

 

But I made the intake manifold be independent of the injectors, so now I can pull intake manifold in probably half the time.

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Due to Bernoulli’s principal you may just be seeing the effect of the air flow speed. What’s your G/sec reading at this pressure? You should be able to compute the air velocity at your test point and see how much pressure drop to expect in an ideal situation.

 

Ok here is a log from today, sadly my manometer doesn't actually "log", it just shows me the min/max over a duration. Peak intake depression tends to happen at about redline.

 

g/rev	RPM	PSI	g/s	MAF V
1.22	2084	0.22	42.89	2.44
1.23	2089	0.38	43.32	2.48
1.24	2136	0.53	45.02	2.54
1.26	2170	0.73	46.64	2.54
1.28	2206	0.95	48.9	2.6
1.31	2296	1.21	49.16	2.58
1.34	2302	1.46	53.18	2.66
1.36	2391	1.75	56.44	2.7
1.41	2414	2.05	57.1	2.7
1.44	2486	2.43	59.07	2.74
1.46	2520	2.76	64.1	2.88
1.53	2566	3.16	67.35	2.82
1.56	2641	3.57	71.96	2.92
1.64	2694	4.05	75.81	3
1.68	2773	4.55	80.99	3.04
1.72	2792	5.13	84.94	3
1.79	2856	5.87	87.35	3.12
1.83	2942	6.51	94.37	3.12
1.88	2997	7.35	99.06	3.28
1.98	3063	8.11	106.89	3.34
2.05	3139	9.08	113.39	3.38
2.22	3212	10.36	122.52	3.42
2.3	3266	11.57	132.57	3.54
2.37	3321	12.86	134.86	3.56
2.38	3419	13.23	137.03	3.56
2.37	3479	13.37	137.93	3.58
2.36	3574	13.39	144.12	3.56
2.37	3680	13.39	144.71	3.6
2.39	3730	13.43	150.49	3.66
2.4	3854	13.42	154.35	3.68
2.42	3883	13.43	159.64	3.74
2.43	3973	13.42	162.24	3.76
2.46	4067	13.37	167.74	3.78
2.48	4129	13.4	169.47	3.82
2.47	4251	13.37	176.69	3.86
2.5	4365	13.32	182.2	3.9
2.51	4428	13.34	186.64	3.94
2.52	4569	13.21	194.42	3.94
2.52	4626	13.27	193.39	3.96
2.5	4724	13.19	198.55	3.98
2.51	4750	13.15	199.75	4
2.49	4934	13.12	204.5	4.02
2.48	5005	12.97	206.11	4.04
2.47	5063	12.9	210.51	4.06
2.46	5197	12.82	213.44	4.08
2.46	5236	12.79	215.99	4.08
2.44	5339	12.64	218.56	4.1
2.43	5409	12.55	219.86	4.12
2.42	5505	12.46	224.54	4.14
2.43	5587	12.37	227.53	4.16
2.42	5736	12.33	229.24	4.16
2.4	5764	12.19	231.86	4.18
2.4	5906	12.19	233.4	4.22
2.42	5923	12.34	242.84	4.24
2.42	6024	12.49	243.94	4.26
2.42	6096	12.6	244.24	4.26
2.38	6179	12.53	246.54	4.24
2.36	6252	12.41	247	4.26
2.35	6410	12.36	250.02	4.26
2.31	6486	12.23	247.48	4.26
2.3	6486	12.23	247.22	4.28

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I don't think we can trust Subaru's g/sec calculations though, they are arbitrary :lol:

 

When I has the intake flow benched it was only off by maybe 3% up top, so The G/sec is less arbitrary then people give it credit for. The reason everyone is chasing their rears trying to get a AFR they expect has to do the the crazy number of compensation tables our ECU’s have, non leaner injector flows, air/fuel resonance issues, and even combustion effects that change the measures AFR. Some people have found timing and AVCS effecting their wideband reading. Timing can’t change now much air the motor is flowing (beyond provinging more turbo drive energy)

 

I've been wanting to build a custom 3" inlet anyway. Since I had the manifold off for another issue, I test fitted it this weekend. I need to figure out a way to add a BOV port, and one 5/8" breather port still.

 

WARNING this picture contains spoilers of what's to come in next couple weeks....

 

TGV delete testing at last!

 

We’re you able to get the 3” pipe lined up with the turbo center line, or did it require an offset couppling?

 

Also noticed you have your block and head breathers tied together. Wouldn’t that cause the heads to breath in crank case gasses instead of fresh air at medium loads?

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When I has the intake flow benched it was only off by maybe 3% up top, so The G/sec is less arbitrary then people give it credit for. The reason everyone is chasing their rears trying to get a AFR they expect has to do the the crazy number of compensation tables our ECU’s have, non leaner injector flows, air/fuel resonance issues, and even combustion effects that change the measures AFR. Some people have found timing and AVCS effecting their wideband reading. Timing can’t change now much air the motor is flowing (beyond provinging more turbo drive energy)

 

Oh right forgot to mention, since I'm on a cold air intake my scales are multiplied by 25%. I have no way of knowing if my intake is actually 25% better, it's just the math that I did to get it back inline with target boosts and engine loads. Thus my MAF Voltages are accurate, but grams/sec are moot.

 

Now with that said, perhaps getting airbox flow measured is not sufficient enough, perhaps we need to do airbox + inlet too?

 

TGV delete testing at last!

 

Ding ding ding. I wasn't gonna do it for another couple weeks, but I developed a fuel line leak, which required me to pull the manifold to tighten them up :spin:.

 

I'll gather more data before I make that long winded post :lol:.

 

We’re you able to get the 3” pipe lined up with the turbo center line, or did it require an offset couppling?

 

Offset is a must, there is just no way that even a 2.4" inlet can fit without hitting the TGV housings, I preground one of the TGV holes. I tested with Agency Power one, but I might get the AMR one too, and see which one fits best.

 

 

Also noticed you have your block and head breathers tied together. Wouldn’t that cause the heads to breath in crank case gasses instead of fresh air at medium loads?

 

That one is little confusing looking but it should make sense:

 

Valve cover has two sets of breathers on each side, one is 5/8" and connects to a metal pipe that goes to the other head, it's there to stabilize pressure between the heads, I didn't touch this one.

 

The other hose is the 1/2" one, this one connects to the plastic Y pipe that connects to the other head and goes to the inlet. Lastly we have the PCV system, which also has also has a Y connection from crank to PCV Valve -> plenum and the other end goes to the inlet.

 

I teed the 1/2" breath inlet connection to the PCV connection, and sent the feed to the inlet. In theory it should work fine since both lines were on the inlet anyway, maybe it's getting less airflow now? But that's not always that bad, my oil consumption went down after I switched to the perrin inlet and this teed configuration, which now makes sense, since stock PCV location is seeing 2x the vacuum amount.

Edited by covertrussian

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Due to Bernoulli’s principal you may just be seeing the effect of the air flow speed.

 

Just came across a post that actually touches this point over at NASIOC.

 

Don't jump to conclusions like this. Intake-flow efficiency isn't as simple as measuring pressure-drop.

 

As an example, the stock VF-39 should be able to flow around 32 lbs/min, which at 75*F translates to 431.3 CFM. At that massflow rate and density (.0742 lbs/CF), the velocity of the air through the 2.08" diameter compressor inlet should be around 207.69 mph. (304.47 ft/s) Assuming the flow is incompressible and inviscid, the static pressure drop, due only to the Bernoulli Principle, is around 32.7 inches of water.

 

So, even at 42" of water, (if you measured at the compressor inlet) only 9.3" of that is due to intake restriction. You'd still have around 33" of pressure drop at the intake side of the compressor wheel even with no filter or intake tube at all.

 

Also, if you're interested in learning more about the Bernoulli Principle, try installing your pressure probe at the filter and then at the intake side of the compressor; the readings will be different.

 

FWIW, when engineers talk about flow efficiency, they talk about enthalpy and changes in density, and not usually pressure-drop.

 

-Adrian

 

edit: 42" H2O = 1.5psi ... and 9.7" H2O = 0.36 psi ... not exactly a huge restriction. heh

 

They also bring another great point in the following post.

 

That's nice, but you still missed the point: there is going to be some pressure drop even with zero resistance to flow at any given intake velocity. It's easily calculated as shown.

 

At peak flow the inlet of the stock VF-39 will have at least ~33" H2O with no intake restriction at all due to the velocity of the air going into the inlet.

 

Knowing only the pressure drop without knowing the velocity of the air tells you absolutely nothing about the resistance to flow.

 

There's one other way to see how restrictive an intake is and that's the check the wastegate tables for a given massflow; if the required wastegate duty cycle increases for any given massflow, temp and RPM when the intake is removed, then you have removed some restriction to flow because now the turbo doesn't require as much energy to push in the air.

 

That's actually how one of my friend's, whom writes the ECU's for one of the GM brands, checks to see if a particular new part has changed the resistance to flow in the engine.

 

-Adrian

 

When doing the CAI originally I saw about 25% increase in boost, requiring me to reduce WGDC's by 25%. Now I wish I still had my stock EBC hooked up, if I could get a 6ish psi gate I would run the stock EBC again.

 

 

I'm in process of acquiring parts to build the 3" inlet (mainly the BOV and breather pipes). Once I get those we'll see how much vacuum is at that turbo with a much bigger pipe. Also planning on testing the stock pipe too here soon.

05 LGT 16G 14psi 290whp/30mpg (SOLD)

12 OBP Stock 130whp/27mpg@87 Oct

00 G20t GT28r 10psi 250whp/36mpg

22 Ascent STOCK

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  • 4 weeks later...

I wasn't planning on doing the TGV deletes until it got warmer (which is basically now), but in early April I opened the hood and was greeted with this wonderful sight.

http://legacygt.com/forums/attachment.php?attachmentid=265022&stc=1&d=1526009508

 

I don't know why Subaru decided to mount that clamp upside down, but that meant the manifold had to come off to tighten it enough to stop the fuel leak.

 

I started removing all of the vacuum lines connected to the manifold and intake, was greeted with mayo inside the PCV/Valve Cover breather hoses. This is probably form a fairly cold & humid winter, since water vapor + oil vapor and rapid cooldown seems to cause this.

http://legacygt.com/forums/attachment.php?attachmentid=265023&d=1526009624

 

Started with the removal of all the basics, IC, Throttle Body, Vacuum lines, fuel lines, note I didn't have to touch any coolant lines! I was gonna remove the intake manifold then remove the TGV's after, but this is about as far as the manifold would come off, thus TGV's needed to come off at the same time. Oh with my luck one of the TGV bolts got stuck in the head and the bolt sheered off, I'm impressed that the aluminum thread didn't give out first.

http://legacygt.com/forums/attachment.php?attachmentid=264902&d=1525744372

 

You have to remove the manifold and TGV's in one go thanks to one unreachable bolt under the plenum attaching the fuel rail to the manifold. Once the manifold and TGV's were off I threw away that bolt....

http://legacygt.com/forums/attachment.php?attachmentid=264904&d=1525744372

 

Manifold and TGV's are out, what a mess, makes me appreciate the EJ253 and even the H6's more, they are much cleaner under the manifold.

http://legacygt.com/forums/attachment.php?attachmentid=264903&d=1525744372

 

Shot of the intake runners. Notice the casting marks, that does provide for a future porting possibility...

http://legacygt.com/forums/attachment.php?attachmentid=265025&d=1526009624

 

While manifold was off, I noticed how messy the knock sensor was (thanks to mice). Took the opportunity to vacuum it all up.

http://legacygt.com/forums/attachment.php?attachmentid=265026&d=1526009624

 

With the manifold off, I also took the time to check on the manifold o-rings. I bought spares, but the ones I installed in 2014 still look excellent!

http://legacygt.com/forums/attachment.php?attachmentid=265030&d=1526009624

 

 

Stock TGV vs Deletes Comparison

 

Ok now to the actual TGV's. Stock vs Deleted & Ported engine side:

http://legacygt.com/forums/attachment.php?attachmentid=265027&d=1526009624

 

Stock vs Deleted manifold side:

http://legacygt.com/forums/attachment.php?attachmentid=265028&d=1526009624

 

Even with the TGV's fully opened, this shows how much of a restriction the wall and butterfly still is

http://legacygt.com/forums/attachment.php?attachmentid=265031&d=1526009624

 

There was a ton of oil/carbon buildup after the TGV's, but not so much before. Could be due to added pressure drop (increased vacuum) from the TGV's themselves.

http://legacygt.com/forums/attachment.php?attachmentid=265032&d=1526009668

 

Installed the new TGV's onto the fuel rail, ready to be installed on the head.

http://legacygt.com/forums/attachment.php?attachmentid=264905&d=1525744372

 

I was gonna use the brand new oem gaskets but noticed that original gaskets are far superior to the new oem ones. Original ones should be reusable, while the new ones are onetime use only.

http://legacygt.com/forums/attachment.php?attachmentid=265029&d=1526009624

 

Since I got rid of that pesky bolt, I am able to install the TGV's first and then install the manifold ontop, much less hassle then trying to install the manifold and TGV's at the same time.

http://legacygt.com/forums/attachment.php?attachmentid=264906&d=1525744372

 

Closer look at the TGV's and how they merge into the runners

http://legacygt.com/forums/attachment.php?attachmentid=264899&d=1525743665

 

From here is just assembly in reverse order. For more detailed TGV Delete building and installation see my how to thread: How to Build & Install TGV Deletes

 

While reassembling everything, I decided to fix the problem clamp locations, that way I can tighten them without removing the whole ordeal again. (I hit the IMG tag limit for the post so direct link to image will have to suffice)

http://legacygt.com/forums/attachment.php?attachmentid=265361&stc=1&d=1526869408

 

Testing Data

Unfortunately I couldn't get these done fast enough so the temps did drop by about 5F. To keep it more consistent when it hit same ambient temp as base pulls I grabbed these logs.

 

Intake Air Temps

I did my best to insure that intake and post intercooler temps were the same.

http://legacygt.com/forums/attachment.php?attachmentid=265036&stc=1&d=1526013100

 

Airflow: MAF Voltage & Engine Load

Increased MAF voltage shows more airflow, while this is hard to see in voltages due to their rather low scale, this is very visible with Engine Load. TGV Delete's gained around 10 grams/rev.

http://legacygt.com/forums/attachment.php?attachmentid=265034&stc=1&d=1526012952

 

Fuel: Pulsewidth & Injector Duty Cycle

Seeing a trend of increased fuel usage, higher engine load puts you closer to the next fuel column, which usually demands more fuel. Dyno picture will have AFR's.

http://legacygt.com/forums/attachment.php?attachmentid=265035&stc=1&d=1526012952

 

Timing

Not graphed, but car was fine with same timing at first at 50F, but with slightly warmer temps ecu started pulling 1* up top, thus TGV deletes want 1 to 2 degrees less timing.

 

MPG

City MPG Testing

Before:

37-76F: 19.59mpg

35-70F: 20.77mpg

Average: 20.18mpg

 

After:

43-81F: 21.63

37-75F: 19.13

Average: 20.38mpg

 

Max Gain: 0.86mpg or 4.14% increase

AVG Gain: 0.20mpg or 0.99% increase

 

 

Highway MPG Testing

I couldn't do as many back to back highway MPG tests, simply because of time and cost. City is easy since I have to drive to work everyday.

 

Before:

54-64F: 29.83mpg (Lights 0%)

 

After:

53-64F: 29.22mpg (Night/Lights for 16% of miles)

 

MPG Gain: -0.62mpg, 2.04% loss

 

Since it's a rather small dataset I can't say with certainty that TGV's made me lose highway gas mileage or if having the lights on for 16% was the cuplrit, but what I can say is it didn't gain anything either.

 

I might reinstall the TGV's once I fix the inlet issues and do another comparison.

 

Power

Finally the dyno! Unfortunately that 49F log is off, this has been happening to me a lot more Since I've been scratching 300whp, keep in mind that 5% dyno error is expected, which is ~15whp error!

 

The before and after pulls happened on the same night, but since it took me so long to install the temps did drop from 49F to 43F, which is a fairly trivial change, not even 1hp difference for NA car's.

http://legacygt.com/forums/attachment.php?attachmentid=265033&stc=1&d=1526010717

 

No accurately measurable difference, even when adding or removing 2* of timing. Even with about 10g/rev gain in airflow. This made me started looking for the other issues again, particularly the Perrin inlet possibly collapsing, which I'll detail in the next installment.

 

Bonus points for those that noticed that I didn't apply SAE corrections for Temp or Barometric pressure. I recently learned that SAE's barometric pressure correction shouldn't be used on turbo cars, since the wastegate self compensates for pressure barometric or elevation pressure changes. I didn't use temp correction because it forces barometric correction, with it being only 5F between the runs it's barely a 1hp difference.

 

Another different thing you might have noticed is the smoothing correction. I've noticed smoothing hiding gains, or in most cases inflating gains. Sometimes there will be an odd spike (maybe a slight wheel/clutch spin, or just road inconsistency). These inflated up power spikes are easily detectable with smoothing set to 1, but on higher smooths Virtual Dyno makes it look like there were power gains through the whole range. Unfortunately this makes my life harder because it's damn near impossible to find smooth and straight roads in my area (all hills here).

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120630459_EngineLoad-MAFvandgrams-rev.thumb.png.93e0e10cd4364e3d2fd94a9aa0ec2775.png

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Edited by covertrussian

05 LGT 16G 14psi 290whp/30mpg (SOLD)

12 OBP Stock 130whp/27mpg@87 Oct

00 G20t GT28r 10psi 250whp/36mpg

22 Ascent STOCK

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Forgot to mention, cold starts feel exactly the same as before, no odd idling. But to be fair, it hasn't been below 30F since I installed the TGV delete's. Edited by covertrussian

05 LGT 16G 14psi 290whp/30mpg (SOLD)

12 OBP Stock 130whp/27mpg@87 Oct

00 G20t GT28r 10psi 250whp/36mpg

22 Ascent STOCK

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The pressure valve is only there to let EVAP (fuel vapors) to go into the inlet under boost. When not in boost, the pressure based valve is closed, and an electronic solenoid opens directly into the intake manifold.

 

I'm considering the evap valve delete. Any cons with evap line under boost conected directly to IM?

Edited by leetdrv
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I'm considering the evap valve delete. Any cons with evap line under boost conected directly to IM?

 

Pressurizing your gas tank.

 

What covert did left left the main valve in place, so the ECU can control evap burn off and close this off once in boost. He just removed the circular boost controlled one that doesn't do much.

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A couple day's late, but I see you found out about the gas line leak. Years back I used lock wire to stop that leak. I have posted photo's. I also found out its easier to remove the manifold and TGV's as a unit.

 

I'll assume, when the factory assembles the fuel lines to the manifold, they do it upside down on the bench. Hence why the clamp is upside down when the assemble is installed at the factory.

305,600miles 5/2012 ej257 short block, 8/2011 installed VF52 turbo, @20.8psi, 280whp, 300ftlbs. (SOLD).  CHECK your oil, these cars use it.

 

Engine Build - Click Here

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Came to the same conclusions after my last thrash as well. Fully explains why the mid rail hose clamps are facing the case from the factory. Left the rail hanger bolt out for now till next time. Rails are supported by three other points if I remember right.
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Forgot to mention another fix that I did. While reassembling the fuel rail, I decided to fix the problem clamp locations, that way I can tighten them without removing the whole ordeal again.

 

http://legacygt.com/forums/attachment.php?attachmentid=265361&stc=1&d=1526869408

05 LGT 16G 14psi 290whp/30mpg (SOLD)

12 OBP Stock 130whp/27mpg@87 Oct

00 G20t GT28r 10psi 250whp/36mpg

22 Ascent STOCK

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