The RS6 - 1st gen Liberty EZ30D Conversion

EJ series vehicles with some conversion they didn't leave the factory with...
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Donkeytits1
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Post by Donkeytits1 » Sun Jan 01, 2017 2:27 pm

So now that the engine is in and running, the hurdles are fabrication and packaging related.

Flywheel and clutch went straight on, and the engine went straight in with a bit of manoeuvring. The steel injector rail cover on the left hand side needs to come off so that you can clear the cruise control pump and that's it. Engine was easy to slip onto the tranny with the tranny jacked up and the engine on a tilt adjuster. Tranny engine bolts have plenty of access like it was with the EJ, and the lower engine mounts dropped into their holes without fuss. Every thing is pretty tight in there, with only 15-20mm clearance between alot of things. But nothing hits when the engine kicks.

The top of the engine looks high when its all sitting there. But the hood still clears the engine, even with the beauty cover on. I've only confirmed this by laying a piece of corrugated cardboard down on top of the engine and looking for indents, so I don't know if the gap is 25mm or 5mm. All I know its a 4mm piece of card can fit in between. I'm not worried about damaging the hood with this though. If there is contact, it will be between the flat plastic beauty cover and bonnet ribs, and the extent of the engine movement I have so far observed is not likely to damage or bend anything. I'm just going to suck it and see.

Power steering and feed lines are swapped over as the EZ has a remote reservoir. Cannot use the EJ pump because the integrated reservoir fouls on the intake manifold of the EZ. It is a straight forward swap though, the fittings on the steering rack are the same and the hard lines only need a small amount of bending to adapt to the different hole positions. This can be achieved with a set of multigrips.

The A/C system is all EJ. The hardlines on the compressor need a little bending. The one that goes to the front condenser needs to be bent so that it can clear the intake manifold. The one the runs back to the firewall to feed the evaporator needs to be straightened out a bit to give about an inch more length to account for the longer engine. I tried to do this with the refrigerant charge still in the system, but it was too hard to hold the compressor and bend the lines at the same time. The lines are too strong. Access to the lines around the firewall is limited, and the connection to the evaporator isn't rigid enough to bend the pipes. So I had to recover the refrigerant and bend the compressor lines with the compressor mounted and the connections partially undone. The evaporator line needed to be removed and held in a vice.

The challenges not are fitting the exhaust and finding a suitable gearbox cross member, and sorting out a cooling solution.

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The issue with the crossmember is that the stock H6 headers fit fine - they align with the exhaust hanger and everything - but they interfere with the crossmember in two places. One is on forward LH Side where the crossmember is not sculpted to provide room for an exhaust (see photo) and around the hanger where the two portions of the exhaust merge, one side interferes with the rearmost central sections of the crossmember. I 'have' to use these headers, because they have 3 cats in them and they have pre and post O2 sensors. So deleting cats causes more ECU problems, and buying 3 new cats is expensive. Don't really want to cut and shut the headers as I'd loose all the heat shielding and if I ever needed to replace them it would be another custom job. The rear cat would need quite a dodgy joint aswell. I've been researching crossmembers the last couple of days, and asked a few subaru nuts, and the results of this are that turbo cross members have the LH side sculpted for dual exhausts, and it seems some versions also have more clearance around the exhaust hanger too. The bolt pattern at the chassis is the same. So once wreckers are staffed again, I'll go for a look around and see if I can avoid modifying the exhaust. Who thought a 2001 6 cyl exhaust would fit under a 1993 4 cyl car?? stoked.

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[Credit: Team Scream at Subaruforester.org]

Picked up a full 3" stainless steel exhaust system for a turbo RS liberty a week or two ago for $100. Again, stoked. A slight modification should see that mate up to the headers nicely. And stainless is nice to weld :D

Up front, cooling is an issue, and I think the only good solution is a custom radiator. As the engine is 1 to two inches longer than the EJ, space up front is suddenly at a premium. The fact the that EZ has two outlets at the top is also a complication. The EZ and EJ radiators are essentially the same size, but the EZ has a top bottom tank design and the lower rad outlet is dropped down an inch or two below the bottom tank. This interferes with the chassis on the new car. The EJ radiator still drops in, and I have dodged up a manifold that can join the two coolant outlets. But there is absolutely no space left for rad fans that way. Seeing as I don't want to modify the chassis or the rad support, the only solution really is a top tank aluminium radiator with slimline fans. This will allow me to use the stock EZ hoses, which will be neat and leave enough length for good hose flex, and there will be space for some slimline fans. Dunno how much it will cost though. Depends how modular they are. In the mean time, I'll use the dodged up manifold and have no radiator fans. I think fans will be a necessity, as the front of the engine is so big and flat! Its like the air comes through the radiator and hits a brick wall. So while passive cooling was never a problem with the EJ, now we will probably have a reduction of passive airflow and when driving hard there will be at worst a 60% increase in cooling load. I guess again, we'll suck it an see. Not like I can shave the sides of the cam cover off or anything.

Will keep youze updated

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El_Freddo
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Post by El_Freddo » Sun Jan 01, 2017 5:37 pm

Speak (PM) Venom - he ran a H6 in a gen2 with the stock radiator and an adaptor pipe for the twin outlets of the H6 and one thermo fan - I believe it was from a fiori (Subaru) which has the thinnest factory thermo fan.

That setup kept sh!t cool even I soft sand on a hot summer's day.

Still a top effort mate. I'd be in minded to do the same after you've pioneered this conversion. But that said, I doubt Mrs El_Freddo would allow that since I'm working on an RS lib...

Keep up the good work and the awesome write ups ;)

Cheers

Bennie
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Donkeytits1
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Post by Donkeytits1 » Sun Jan 01, 2017 6:46 pm

This would be his here yeah? Before he bought it off turbo yoda
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[Thread:New Family Wagon, H6 EZ30 97 Liberty]

I've attempted the same thing, but I have a little less room in the front and limited fabrication capability at home so its hard to build up something nice (have to drive to the workshop and back to weld stuff, even to tack)

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So this'll do me until I need to put fans in. Then I'll go custom I reckon. Having no manifold will be a big plus. Even Venom's car looks tight in there.

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Donkeytits1
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Post by Donkeytits1 » Sun Jan 01, 2017 7:25 pm

Heres a quick pic of the side rail clearance while I have stuff removed

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In the process of welding the power steering reservoir bracket onto the ABS module bracket

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Donkeytits1
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Post by Donkeytits1 » Sun Jan 01, 2017 7:30 pm

The ABS module bracket provides a convenient spot to mount the power steering reservoir bracket. Excuse the disgusting welds.
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And it all fitted up
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The EJ cables are also a bit longer. Conveniently, there were some spacers left over from a rubberised grommet somewhere on the Outback.
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Post by Donkeytits1 » Wed Jan 04, 2017 12:02 am

Another big day of wins.
Got to Dapto pick-a-part this morning and got myself a gearbox crossmember with a bit more clearance

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Seems like pretty much anything gen 2 or newer have that extra clearance on the LH side, and they have redesigned the cross member a couple of times. Some are more boxed in and stronger than others (this appears to be the older models and turbos), and some have a slightly different transmission mount height (old models look consistent, phase two 5 speeds, which I only was able to see in imprezas, look like the mounts lower). So I chose to take one off a gen 2 liberty as the rest of the cross member is exactly the same. I bought the whole cross member, but only changed the part shown in the photo. No other crossmembers have extra space around the tail shaft end which is unfortunate.

Went to an exhaust shop and picked up a bend, a flange and some gaskets to get the exhaust underway.

My good friend and housemate, who works part time at a motorsports engineering shop specializing in exhaust manifolds, helped me cut and shut the exhaust. Started by removing the heatsheild, mounting the manifold on the car and making some marks.

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Then went to the welder, tacked the header flanges flat to the welding table and removed the offending section of pipe.

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After building up and welding in the modified section, ground the tacks off and she's done.

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My friend is a genius. They fit great, and the welds pulled less than 5mm at the header flanges.

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Once placed on the hanger, there was a small interference on the LH side where the heat shield still contacted the cross member. Solution to that was to jack the exhaust up onto the cross member crush the heat sheild down. Now there is about 5mm clearnace, so it will probably hit a little. If the contact is annoying, regular or bad I will fix it. But we'll see how it goes.

Oh, and the intake from the H6 bolts up almost exactly where the old airbox used to go. So no custom solutions required there. Zero. Zip. Not even some flexible hose. Who would have thought that.

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So headers are done. Only thing left to do with the exhaust is the make a small joiner section to mate onto the rest of the system

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Post by El_Freddo » Wed Jan 04, 2017 9:48 am

That's the one (above post of Venom's H6).

Neat work on the exhaust!

The air box fitment does t surprise me - Subaru essentially have not changed the engine bay layout in a very long time! Lego!

How long until you reckon you'll be driving this? And I bet it sounds a bit better with the extractors on it to the mid section!

Cheers

Bennie
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pitrack_1
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Post by pitrack_1 » Thu Jan 05, 2017 1:47 am

Great work again and happy it's going well for you with minimal delays/detours/decoys/diversions.

Just remember to remove the shifter before you close the bonnet (did something like that myself...once..! :-)

Will the battery space be big enough to hold a 6-cyl battery?
Patrick
Ex- 2010 Forester Diesel

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Donkeytits1
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Post by Donkeytits1 » Thu Jan 05, 2017 10:12 am

Haha! Yeah the shifters gone - or as we know it - the Swedish Nut Lathe

I'm gonna keep using the battery that was in the 1st gen car. It was originally speced with a puny 40 Amp hour thing. I enlarged it to 60 amp hour around a year ago. That's the biggest battery that will sit in the battery cradle. The H6 looks like it has an 80 Amp hour, but the little battery has more than enough power to crank it. And conveniently, the H6 battery fits in another car we own. So ace.

Benny: Yeah 'Lego', holy sh!t, I don't believe it. Its making it too easy! It won't look modded enough bro, I'll get no cred! :P

Should be driving tonight once I stick my hacked up rad system in. Exhaust will be ending at the headers, so won't have to tell the neighbours, they'll know whats happening.

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Post by pitrack_1 » Thu Jan 05, 2017 3:41 pm

Donkeytits1 wrote: Should be driving tonight once I stick my hacked up rad system in. Exhaust will be ending at the headers, so won't have to tell the neighbours, they'll know whats happening.

...It won't look modded enough bro, I'll get no cred! :P
If you are in Canberra esp Northside with Summernats on can I suggest don't unless you're 100% sure it's absolutely, perfectly legit on road? I think the cops are just looking for excuses...:-o

...But the 'no mods' look just might save you :-)
Donkeytits1 wrote:Haha! Yeah the shifters gone - or as we know it - the Swedish Nut Lathe

I'm gonna keep using the battery that was in the 1st gen car. It was originally speced with a puny 40 Amp hour thing. I enlarged it to 60 amp hour around a year ago. That's the biggest battery that will sit in the battery cradle. The H6 looks like it has an 80 Amp hour, but the little battery has more than enough power to crank it. And conveniently, the H6 battery fits in another car we own. So ace.
Good stuff. Just replaced a battery in our 2.2l Mazda diesel, the NRMA took it from ~60Ah to 90Ah. Should run South Aust. for 20 mins or so in an emergency ;-)
Donkeytits1 wrote:Benny: Yeah 'Lego', holy sh!t, I don't believe it. Its making it too easy!
No not too easy, just the result of good research and prep. Well done! :cool:
Patrick
Ex- 2010 Forester Diesel

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Donkeytits1
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Post by Donkeytits1 » Fri Jan 06, 2017 1:40 am

(Obs a youtube vid stuffs your post up)

[youtube]w84SZGnIPwQ[/youtube]

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Post by Donkeytits1 » Fri Jan 06, 2017 1:49 am

No exhaust. Only an hours worth of work to get the central joiner piece made, but couldn't wait. Just had to drive it ...and test it for 4 hours.

Here is the radiator. EJ22 spec with 2 puny fans, 1 12" (really 11.5") Davies Craig I scored for free and a $65 10" from supersh!t mounted on aluminium channels, which are surprisingly stiff. The Davies Craig fan feels allot more efficient than the supercheap one.

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The manifold pipe worked really well for something that I was only really expecting to be temporary. The hoses I used are some short sections of the EZ hoses and the half crushed larger bend is from a VL commodore. Really any 90 deg bend would have worked, the como pipe just happened to have the sharpest bend in it. Ideally, a pipe that bends back on itself before straightening out again would be ideal. There was the perfect one there to, but it was for a barina and diameter was too small. Damn it.

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Bleeding the system was finicky and a pain, and it seemed like it took 40 litres of water to fill. Was very hard to get the heater/thermostat circuit bled, with no heat coming out until we purchased a longer funnel from the servo we were stranded at. After that, the EJ radiator and the Davies Craig fan on its own easily kept the car cool on a 22 degC night, fan only required when idling in a car park. Cycling between 86-93 decC. I have no doubts that the supercheap fan will handle the A/C load when I get it recharged. The performance of those little fans, even unshrouded, is better than I expected.

Electrics were faultless, except for an eratic taco. I know I killed the drop down driver of the micro controller some how, but that didn't seem to worry the FET I'm using to drive the output in testing. Perhpas it is now. I'll just need to pull the board out and have a look. Other than that, no codes, no problems.

One thing that did happen, and it was making me worried early on, the car was burbling, surging, producing idle control Check Engine Light errors and the speedo wasn't working. The speedos mechanical, so that was an easy fix, the drive cable had fallen out. Then it clicked what was happening. In the speedo there is a reed switch which sends pulses to the ECU under the "Speed Signal 2" input when the cars moving. With the speedo dead the ECU wasn't getting this signal so it was trying to control the idle, which it couldn't do because the car was being driven under all sorts of varying loads. So it went a bit mental. SO what it was doing was at small throttles it was retarding the timing (or something) under 10% TPS, sometimes surging and bucking, and not cutting fuel on deceleration, which was causing all sorts of awesome key-banger like pops. This sounds exactly like the problem Venom was writing about before it seems like he got jack of it and sold the car. I'm guessing Al (turbo Yoda) would have known about the Speed input 2 when he built the car, but maybe not. maybe it wasn't hooked up.

At one point I had to stop because there was an ABS light came on, and even with the key off the motor in the ABS module was stuck running! Had to remove the fuse to cut it. The ABS and the engine electrics are not connected, so I have no idea why this happened. Have to see if it does it again.

Oh and the power steering pump is noisy. Sounds like the levels low and there's is air in it. No idea why, it wasn't bad in the donor car. It was drained, and the new powersteering fluid I put in turned to foam as soon as it went in. So hopefully it just defoams and is right tomorrow.

Anyway, I'm so stoked today. Car feels so different from what it did with the EJ. Definitely more powerful, but I don't know if its as nice to drive. Currently I'm driving it like an unco, because I'm not used to having 3/2 the firing frequency and with the exhaust off all I can hear is drone and interior rattles. Broken taco also doesnt help, I seem to naturally drive at 2/3 the revs now. Only ever owned 4 cyls.

SO I guess next I'll get this 3" catback system mated up and see how it goes. Put some proper coolant in and make sure the car is reliable. Then its back to daily duties :D Hopefully the exhaust is quet enough and doesn't drone.

Oh, and rig up the DCCD controller and put the R180 for all the skids yo:P

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Post by Donkeytits1 » Fri Jan 06, 2017 2:07 am

Oh and patrick: I live in Wollongong now, not Canberra. Know what Summernats is about though, used to live in Watson on the side closest to EPIC. House would stink of rubber for weeks

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Post by Venom » Fri Jan 06, 2017 11:00 am

Awesome build thread mate, great job. Wish I still had my green H6 Lib with you doing all this, it would probably work out a couple of the issues I had with it.

The H6s are loud and droney. See how a 3" exhaust goes but you'll probably want to step down the muffler to something really good quality and 2.5".
[SIGPIC][/SIGPIC]

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Post by pitrack_1 » Sat Jan 07, 2017 12:02 am

Donkeytits1 wrote: Oh and the power steering pump is noisy. Sounds like the levels low and there's is air in it. No idea why, it wasn't bad in the donor car. It was drained, and the new powersteering fluid I put in turned to foam as soon as it went in. So hopefully it just defoams and is right tomorrow.
Noisy+foamy power steering pump: perhaps see this thread elsewhere and links therein: system bleed and known O-ring issues..

And do you think the extra weight of the 6-cyl over the front-end has changed the handling/ride height- will you need to reset it or alter the suspension?
Donkeytits1 wrote:Oh and patrick: I live in Wollongong now, not Canberra. Know what Summernats is about though, used to live in Watson on the side closest to EPIC. House would stink of rubber for weeks
No probs, it says "Canberra" in your location still. As for me, I'm in Kaleen so I tend to hear Summernats when the seabreeze blows in, but haven't received the smoke yet & tend to hear more of the 'testing' or 'practice sessions' that go on along the Barton Hwy. But I used to live in Sydney where I could hear the Parramatta Speedway when the wind blew from a similar direction so it just another nice memory from my childhood!

Cheers and keep up the good work!
Patrick
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Post by Donkeytits1 » Sun Jan 22, 2017 8:24 am

So, I've got some catching up to do with this thread!

POWER STEERING:

Bleeding the power steering was an absolute bastard in this car.

Basically, because I changed the pump and reservoir over I introduced allot of air into the system and every time I ran the car it was getting whipped up into a strawberry milkshake. Logic was telling me its just a pump and a loop, so air will just pass through till it floats up to the top of the reservoir and escape. Of course the pump and other parts in the system chop up the bubbles into a pink frothy mess that isn't going anywhere.

The system was noisy, and it kinda half worked so I figured stuff it, I'll just go on testing other things

So read some forums, watched about 15 youtube videos, spoke to a friend who's a foreman in a Holden workshop and a mate who's just really handy with cars - Same thing. Fill it up, turn the wheels from side to side until bubbles stop coming out of the tank, keep adding fluid to keep the level right, let it sit, do it again (on jack stands of course), then the small amount of remaining air will just come out over a drive or two. This flat out did not happen, and it was strawberry milkshake for lunch every day with ATF pretty much covering half the engine bay

So I made the "Bleed Bong"

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I'm sure I'm not the first to come up with this solution, but the idea is bypass the reservoir and have enough ATF volume there that the system can suck up fresh non frothed fluid for enough cycles to blow the air out.

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This worked a treat. The froth came out and the pump stopped whining in about 5 seconds. Waited for the froth to settle out and ran it again for some time and was still quiet and no more froth.

With an empty reservoir it became apparent what was going on

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There is a filter mesh at the bottom of the reservoir, and air cannot pass through it easily. In fact I watched a big bubble sit under there for about 4 hours without coming through. This is above the inlet and outlet to the reservoir, so air just circuits in and out under this mesh and can't escape. There seems to be a hole where it can come up above the return feed, but a big bubble was getting stuck under the mesh all the time. So I guess the Youtube way could eventually get the air out, but it didn't work for me over three days.

So basically, after using the bong I carefully lifted both the hoses up and joined the reservoir back up making sure to introduce no air into the lines (by making sure the lines and reservoir where full of ATF and that no air was trapped in the join) This was messy - but everything was already a mess at this point. I was then able to move the reservoir around to get all the air out from under the mesh. I actually poked a hole in the mesh before I realsised there was that there was that other hole near the return hose.

Power steering has been 100% fine since. Didn't need to let it sit for 12 hours like I read somewhere.

I think the bong could be useful when trying to troubleshoot a noisy pump. By running it from the bleed bong, you can eliminate air in the system as a cause of the noise.

ALSO NOTE: Don't use EPDM heater/coolant hose, use proper nitrile hose for ATF. Those hoses where all I could get at the time and where intended to be temporary. They went soft and goey in no time!

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Post by Donkeytits1 » Sun Jan 22, 2017 8:27 am

FINISHED THE EXHUAST:

And it sounds awesome.

Made up this little section of pipe

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and a 3" RS Liberty exhaust fitted in no problem.

I seem to be lucky in that a $100 second hand exhaust is one of the best sounding NA 6cyl exhausts I've heard, and it doesn't drone. Loud enough to know its there, quiet enough that it doesn't yell hey I bought this exhaust when I was 17 and got a shitty cannon coz its what my said woz sick. You can easily listen to music and talk to passengers with the front windows down. Couldn't be happier with it.

Apparently it was a $2,300 system (with dump pipe) when the original bloke got it made up. I guess it pays to spend a bit on your mufflers and someone who knows what they're doing!

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Post by Donkeytits1 » Sun Jan 22, 2017 8:28 am

FIXING DRIVABILITY ISSUES AND REV HANG:

It drives like a proper manual now.

I did three things, and I kinda did them all at once. So I don't know if it everything is having an effect or just one thing. I should have done more testing in between. I guess I'll update this little section in the future once I learn more.

1) Clean the idle air control solenoid valve - This was all gunked up with PCV blow by goo. Its pretty delicate, and makes rapid changes in position, so it is understandable that being buked up with goo will slow it down. It was operating allot better once clean

2) Cut off the "Air assist" circuit - Something I would ideally not do, but is a large part of the problem I think.
Basically, the "Air assist" circuit bleeds air to some little jets positioned around the fuel injector nozzels. The idea being, a jet of air is fed into the injector spray to help atomise the fuel and aide complete combustion. EJ WRXs have this "air assist" feature aswell.
The problem is, the air assist bleeds enough air for the engine to idle on its own (I tested that) and the computer must act to shut off the circuit. What I think was happening is the ECU waits around half a second to sense whether you have indeed began to coast and then it actuates the idle air control solenoid (which doubles as the air assist control valve) to cut off the air assist suddenly. During this time, there is enough air being bled to hold the revs to around 3000RPM which when shifting delays the upshift and when decelerating the sudden cut creates a sharp drop in engine torque which triggers transmission windup and oscillations (mini "kangaroo hops", or the familiar jerkiness manual subaru drive trains have when you give them a sudden throttle input in a low gear).
With the air assist blocked, (i'm pretty sure) the rev hang is reduced and the sudden uncontrollable drop in torque is pretty well eliminated.

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IMAGE: This is how the idle air control solenoid valve controls the air assist bleed. Basically the valve moves "beyond closed" and covers the hole for the air assist witha s econd valve plate. This can only occur when the main valve is fully closed, so the ECU needs to be certain that deceleration is intended and that the manifold vacuum is not to high (read point 3) which is what I think causes the pause and the rev hang

3) Install an orifice plate under the idle air control solenoid valve so it limits how much air it can bleed.

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PHOTO: The INLET is on the airbox side of the throttle plate, the outlet is on the engine side of the throttle plate. The "air assist" is not blocked off in this photo. To achieve the block, I just replaced that small hose with rubber plugs.


The orifice plate is a real bodge up with a hand drill. But it'll do. The air doesn't care where the hole is.

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The idle air control solenoid valve does two things. 1) It controls the idle speed to maintain consistency whether A/C on or off, whether the engine is hot or cold, whether the air cleaner is clean or blocked, basically any external influence. 2) It acts to prevent a sudden vacuum forming in the manifold when the throttle is snapped closed, which is a condition that produces a temporary lean mixture and a large amount NOx emissions.
Basically in this car, in order to do this the idle air control solenoid valve seems to be in a closed loop control circuit with the Manifold Absolute Pressure sensor and it oscillates between fully open and partially closed while it figures out where it is meant to be to allow the revs to drop in a controlled manner. My theory is it is opening up too much as the throttle is released and the revs are hanging while it oscillates and figures out what its meant to do.
To dampen this effect, I've put an orifice plate so as the throttle is released, the idle air control solenoid valve can't supply enough air to hang the revs. Enough air still goes through to prevent the sudden vacuum forming (although not as well as before) and the idle can still compensate for A/C etc.
This may have an adverse effect on NOx emissions, but really, I need a drivable car first and foremost and I've tested that the revs still drop in a controlled fashion, much better than if the idle air loop is blocked completely.

So ideally air assist is a good thing and so is limiting the vacuum. But they are making the car difficult to drive. When this engine came out as an automatic, almost all of this would have been masked by the transmission and its torque converter, so its possible the systems are not as refined as they could be if this engine was released as a manual.

I am going to continue fiddling with these systems and determine whether air assist has a noticeable effect on fuel economy and whether I have the optimal sized hole in the orifice plate. Or, whether cleaning the valve negates the need for the orifice plate at all.

Andy

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Post by El_Freddo » Sun Jan 22, 2017 11:50 pm

How did you get rid of the "rev hang" as you call it?

Awesome score and setup on the exhaust! I'm keen to hear this thing in the flesh!

Cheers

Bennie
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Post by Donkeytits1 » Mon Jan 23, 2017 10:28 pm

Updated El Freddo, read above.

Also, to stop the Taco dancing around I added a filter cap to my circuit

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Looks like with all the wiring bunched up and tied together I'm getting some noise in my Taco input wire that I wasn't getting before.

Oh and my radiator split in half, so I embarrassingly got towed home

Image

Thanks NRMA!

Should point out: The seal between the tank and the core failed on the LH, or radiator cap side. So was not caused by the swap ie me :)

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