My Questions:

1). As opposed to a voltage clamp, has anyone tried a 2 or 4 BAR map sensor? Since the problem with a MAP sensor is the voltage goes out of range on boost, does a boost specific MAP sensor have a different voltage range? I'm just not convinced that the clamp method is the greatest idea. Prove me wrong.

The problem here is what kind of engine management do you plan on using? If you're going to leave the factory ECU in place, then you need to leave the factory MAP sensor in place, with a voltage clamp.

2). There seems to be some debate as to whether an intercooler is any use on 5-6psi. Has anybody tried with and without? I'm of the thought that cold boost is always better, but how much heat is even made by 5-6psi?

Z31's of old were not intercooled and it does save some of the lag involved with an intercooler. It's just so easy to put a top mount on one of these...why not? So your mileage may vary, but I do look forward to results if you go without an intercooler.

3). I've placed my hand on the intake manifold many times when the engine has been running and was alarmed at how HOT it gets. Surely this problem just raises intake air temp which the intercooler has just cooled? I've seen insulating manifold gaskets that apparently make the manifold a lot cooler to the touch, has anybody tried them? Also the coolant gets pumped through the throttle body to heat it which transfers heat to the manifold.

Phenolic spacers. I actually had to buy these for my +T build due to clearance under the intake manifold for my turbo inlet. People do claim that even after the engine has been at operating temp for hours, they can still grab and hold the manifold for an extended period of time. I myself have not tested that!

4). From what I can read, the critical recipe to make these engines last is to not get carried away with boost, run rich AFR's and high octane fuel. Every fuel station here has the american equivalent of 94 as well as 91 and 87. Were people successful with 91? Because running costs of 94 are a noticeable amount higher.

99% of the stations in the states have 87, 89, and 91. I don't know how these compare to other countries octanes, but 91 is our "premium". If you need to run lower octane, you have to be a lot more gentle with your timing. IE much less. the factory ECU is known to shove it as high as 40 advanced, but under boost that's a recipe for disaster.

5). BOV/BPV. I understand that this can upset the AFM metered air in a MAF system, But in a MAP system can I just plumb it back into the pre turbo tract or vent to atmosphere without stalling issues etc?

If your car is MAP, designated by the 1, you're fine venting to atmo.

6). As far as water cooling for the turbo, does anybody run the turbo water line to a header tank for natural convection cooling when the engine is shut off? Or is this unnecessary? I've heard that without this system that water in the turbo can boil and oil can coke up. Also if I bypass the coolant flow from the throttle body, Is this a good place to get a water feed for the turbo?

I have mine plumbed in line with the heater core. the coolant will naturally move through the system due to heat differences after the engine is shut off, but I have no had any issues. Running low amounts of boost should keep heat levels low so you shouldn't have an issue with that. If you do want to be on the safe side, add a turbo timer!

7). I'm using the FMU in series after the stock FPU, the FPU vac line is plugged into the intake manifold after the throttle body, and I'm guessing the FMU boost line is plugged in before the throttle body so it can only see boost? A bit confused here.

I had to modify that rail and remove the factory pressure regulator. your factory unit will see boost where you have it plugged in at, and that's fine. It's a 1:1 rise so every pound of boost it will raise the pressure by 1PSI. Take that in to account when you're tuning your FMU.

8). I've seen a lot of builds on here and it appears lots of people don't worry about an oil catch can. Do they just plumb the breather into the intake before the turbo? I imagine that method could make a mess of everything!

I don't run one, would like to, but I haven't gotten around to it yet. If you end up with too much blow-by that does further reduce the octane of your fuel mixture. Which can lead to bad things.

9). What target AFR's do you guys tune for at 5-6psi on these engines?

If you go too rich, you're sacrificing power, but increasing longevity. Your fuel mileage will greatly suffer if you run it too rich. I'd start somewhere around 12 and bring it up to a maximum of 12.5.. MAYBE 13.

10). Does the stock charcoal canister purge solenoid only open under vacuum? I don't want to be boosting 6psi into that system!

I could be wrong but I believe it has a check valve that prevents boost from entering the canister.

 

The problem here is what kind of engine management do you plan on using? If you're going to leave the factory ECU in place, then you need to leave the factory MAP sensor in place, with a voltage clamp.

My brain wonders what happens to ignition timing after the clamp voltage is reached. I'm not sure if the MAP is a precision calibrated instrument or if the ECU learns and makes allowances for MAP variations.

For example, the MAP sensor measures 1V at full manifold vacuum and reaches 5V at WOT or atmospheric pressure. Could a small DC-DC converter change it from 1V at full vacuum to 5V at 6psi boost?

Just curious. I'll do the tried and true clamp.

Z31's of old were not intercooled and it does save some of the lag involved with an intercooler. It's just so easy to put a top mount on one of these...why not? So your mileage may vary, but I do look forward to results if you go without an intercooler.

Yeah I'm going to put a top mount on, but installing the splitter and a bonnet scoop seems like a bit of a headache. All the pics of these seem to be from photobucket which seems to have shat the bed and are no longer visible.

Phenolic spacers. I actually had to buy these for my +T build due to clearance under the intake manifold for my turbo inlet. People do claim that even after the engine has been at operating temp for hours, they can still grab and hold the manifold for an extended period of time. I myself have not tested that!

Hmmm I guess they would have to do something!

99% of the stations in the states have 87, 89, and 91. I don't know how these compare to other countries octanes, but 91 is our "premium". If you need to run lower octane, you have to be a lot more gentle with your timing. IE much less. the factory ECU is known to shove it as high as 40 advanced, but under boost that's a recipe for disaster.

Australian 91 = American 87
Australian 95 = American 91-92
Australian 98 = American 94. This coupled with cooler IAT should reduce risk of Detonation...I hope!

If your car is MAP, designated by the 1, you're fine venting to atmo.

Psssshhhht! Got it

I have mine plumbed in line with the heater core. the coolant will naturally move through the system due to heat differences after the engine is shut off, but I have no had any issues. Running low amounts of boost should keep heat levels low so you shouldn't have an issue with that. If you do want to be on the safe side, add a turbo timer!

Well that makes things a bit simpler. Thanks.

I had to modify that rail and remove the factory pressure regulator. your factory unit will see boost where you have it plugged in at, and that's fine. It's a 1:1 rise so every pound of boost it will raise the pressure by 1PSI. Take that in to account when you're tuning your FMU.

SPA Turbo told me to run the FMU after the stock FPU on the return, but didn't mention that the stock FPU would add pressure at 1:1. I thought it only removed pressure proportional to vacuum. I actually have no idea now. My thoughts are that if the SPA FMU is tuned at say 6:1 with a 45psi baseline that the total pressure will be 81psi and will override the stock FMU.

:help:

I don't run one, would like to, but I haven't gotten around to it yet. If you end up with too much blow-by that does further reduce the octane of your fuel mixture. Which can lead to bad things.

It's cheap insurance and should keep things cleaner I guess?

If you go too rich, you're sacrificing power, but increasing longevity. Your fuel mileage will greatly suffer if you run it too rich. I'd start somewhere around 12 and bring it up to a maximum of 12.5.. MAYBE 13.

Okay thanks.

I could be wrong but I believe it has a check valve that prevents boost from entering the canister.

That would make sense. Thanks!

 

glad to be seconded by George himself! I still feel a bit new to the boosting game here. My car is broken more than it runs, but I have gained a ton of knowledge in a short time because of it. I expect my little rocket will be back on the road within the month with another 2.5, pretty excited of course.

My brain wonders what happens to ignition timing after the clamp voltage is reached. I'm not sure if the MAP is a precision calibrated instrument or if the ECU learns and makes allowances for MAP variations.

For example, the MAP sensor measures 1V at full manifold vacuum and reaches 5V at WOT or atmospheric pressure. Could a small DC-DC converter change it from 1V at full vacuum to 5V at 6psi boost?

Just curious. I'll do the tried and true clamp.

I still have the factory scoop on my RS with no splitter, with my phenolic spacers and my BOV I'm not even sure I can fit a splitter without modifying it.

My car is an automatic, so I think I've been kind of boned on being able to play with the voltage clamp. I run an emanage ultimate which has a stupid easy built in voltage clamp. I did have it set up in my emanage that at 30-35% throttle the factory ECU would see full throttle because I'd be crossing the threshold in to boost. The automatic transmission didn't agree with this since it got throttle position for load detection and gear selection from that same sensor. The thing short shifted gears so stupidly it may as well been left in 4th. I was able to make my car boost far safer by giving the TPS full range and clamping the MAP, but using a 3psi wastegate and an electronic boost controller hooked to my emanage to keep boost low while at partial throttle. It worked great for months, and how I plan to keep this next "build".

If you're going to keep boost low, and use the factory injectors, I think you could get away with only adding two additional modules. Skipping the FMU. Both are from SplitSec. The VC3-100 Voltage Clamp, and the LSC2-001 Fuel Enricher. The enricher is pretty neat as it keeps the ECU from ever seeing increased fueling so your fuel trims won't go out of whack. Fuel trims are the bane of OBD2 aftermarket turbo setups.

The Enricher is connected to the O2 sensor and the manifold so it can detect boost. Once the user determined boost threshold is crossed it starts to modify the O2 signal. Your ECU will see 14.7 like it wants, but your aftermarket gauge will show the true AFR. The only reason I'm against RRFPR is that once you get around 90psi, the injectors fail to open. I have one of these enrichers in conjunction with my emanage. I have a post in my build thread with how to wire it (in a 2001 at least).

Food for thought, bounce it off your tuner if you have one and see what they think. If I didn't have stupid big injectors for the boost I plan to run (anyone have some 440's to trade for 650's? lol) I'd likely have dumped the emanage already in favor of just the clamp and enricher.

 

2). There seems to be some debate as to whether an intercooler is any use on 5-6psi. Has anybody tried with and without? I'm of the thought that cold boost is always better, but how much heat is even made by 5-6psi?

damnit! silverton beat me to it. none of my 3 z31's had intercoolers. susiemk on here has a boosted 251 (iirc) that his wife drives that is non intercooled. with great results. he talks about it in this thread.

http://www.rs25.com/forums/f7/t107798-ej222-phase-ii-map-2-2l-ej251-turbo-conversion-parts-list.html which also has a ton of info that may apply to you as well.

3). I've placed my hand on the intake manifold many times when the engine has been running and was alarmed at how HOT it gets. Surely this problem just raises intake air temp which the intercooler has just cooled? I've seen insulating manifold gaskets that apparently make the manifold a lot cooler to the touch, has anybody tried them? Also the coolant gets pumped through the throttle body to heat it which transfers heat to the manifold.

second on the phenolic spacers. the coolant in the TB (from what i've read) is there to keep gunk and shit from clogging the IACV. which can cause some stalling issues where the engine won't catch itself when the revs drop to idle. i believe this to true becuase of my car. i have stalling issues every now and then at random. i have had the coolant bypas done for years and years and it makes sense now that i've learned that.

4). From what I can read, the critical recipe to make these engines last is to not get carried away with boost, run rich AFR's and high octane fuel. Every fuel station here has the american equivalent of 94 as well as 91 and 87. Were people successful with 91? Because running costs of 94 are a noticeable amount higher.

i get away with running the US 89 octane with no effects. 93 is better, but more expensive obviously. if i run the 87, under full boost i get detonation. so if i'm being cheap, i have to stay out of boost.

5). BOV/BPV. I understand that this can upset the AFM metered air in a MAF system, But in a MAP system can I just plumb it back into the pre turbo tract or vent to atmosphere without stalling issues etc?

you can route it back in, but its not worth the extra time/brainpower/money to do that with map.

6). As far as water cooling for the turbo, does anybody run the turbo water line to a header tank for natural convection cooling when the engine is shut off? Or is this unnecessary? I've heard that without this system that water in the turbo can boil and oil can coke up. Also if I bypass the coolant flow from the throttle body, Is this a good place to get a water feed for the turbo?

i use the heatercore too. i put the turbo in the way of the return line out of it back to the crossover pipe. before is fine too. it really depends on which way is easiest for you to plumb in.

9). What target AFR's do you guys tune for at 5-6psi on these engines?

same as silverton. i wouldn't push it more than 13. mine hover's around 12-12.5




edit:
apparently i just posted to second everything silverton said. i only answered the ones i had real knowledge on.

 

Thanks guys!

damnit! silverton beat me to it. none of my 3 z31's had intercoolers. susiemk on here has a boosted 251 (iirc) that his wife drives that is non intercooled. with great results. he talks about it in this thread.

I purchased an intercooler today, it might not be necessary but it was like $40 and solves all the intake/bov/plumbing crap in one nice piece. It's from a forester XT and appears to have less fitment issues (firewall) with the stock intake manifold in the Outback engine bay.

second on the phenolic spacers. the coolant in the TB (from what i've read) is there to keep gunk and shit from clogging the IACV. which can cause some stalling issues where the engine won't catch itself when the revs drop to idle. i believe this to true becuase of my car. i have stalling issues every now and then at random. i have had the coolant bypas done for years and years and it makes sense now that i've learned that.

I'll still do the bypass, but good info that I will hopefully remember.

i use the heatercore too. i put the turbo in the way of the return line out of it back to the crossover pipe. before is fine too. it really depends on which way is easiest for you to plumb in.

Okay, I don't know heaps about Subaru turbo cars (but have built NA engines/gearboxes etc etc. Is the crossover pipe the metal pipe that runs along the intercooler? Or is that a crankcase breather pipe?

 

Thanks guys!



I purchased an intercooler today, it might not be necessary but it was like $40 and solves all the intake/bov/plumbing crap in one nice piece. It's from a forester XT and appears to have less fitment issues (firewall) with the stock intake manifold in the Outback engine bay.

that's the one most use for becuase of fitment issues with the stupid metal bugeye ones.

Okay, I don't know heaps about Subaru turbo cars (but have built NA engines/gearboxes etc etc. Is the crossover pipe the metal pipe that runs along the intercooler? Or is that a crankcase breather pipe?

that's the valve cover breathers and what not. if you follow the two heater core hoses from the firewall then under the torque box on the intake mani back around to the other side of the engine, they go into two metal pipes. one goes directly to the water pump, or well, the water flows from the water pump. the other is the return that connects into the coolant crossover pipe under the intake mani.

with the turbo you're just adding it into the loop.
waterpump>metal pipe into rubber tubing>into heatercore>out of heater core>rubber tubing into turbo>turbo to rubber tubing> tubing back to metal crossover.

i'm pretty sure the actual from the factory turbo cars are different. this is just how we as NA-T'ers plumb it in.

 

My car is an automatic, so I think I've been kind of boned on being able to play with the voltage clamp. I run an emanage ultimate which has a stupid easy built in voltage clamp. I did have it set up in my emanage that at 30-35% throttle the factory ECU would see full throttle because I'd be crossing the threshold in to boost. The automatic transmission didn't agree with this since it got throttle position for load detection and gear selection from that same sensor. The thing short shifted gears so stupidly it may as well been left in 4th. I was able to make my car boost far safer by giving the TPS full range and clamping the MAP, but using a 3psi wastegate and an electronic boost controller hooked to my emanage to keep boost low while at partial throttle. It worked great for months, and how I plan to keep this next "build".

I am truly thankful that I have a 5MT :noes: All this learning about turbos and stupid smart ass ecu's is enough!

If you're going to keep boost low, and use the factory injectors, I think you could get away with only adding two additional modules. Skipping the FMU. Both are from SplitSec. The VC3-100 Voltage Clamp, and the LSC2-001 Fuel Enricher. The enricher is pretty neat as it keeps the ECU from ever seeing increased fueling so your fuel trims won't go out of whack. Fuel trims are the bane of OBD2 aftermarket turbo setups.

The Enricher is connected to the O2 sensor and the manifold so it can detect boost. Once the user determined boost threshold is crossed it starts to modify the O2 signal. Your ECU will see 14.7 like it wants, but your aftermarket gauge will show the true AFR. The only reason I'm against RRFPR is that once you get around 90psi, the injectors fail to open. I have one of these enrichers in conjunction with my emanage. I have a post in my build thread with how to wire it (in a 2001 at least).

Now this...is flippin' genius!

Now say I was to use the FMU (what a shame I spent forever reading up on them and finally found the perfect one that wasn't a fixed ratio ebay POS), what will the fuel trim effect be? I was under the impression that the stock ECU ran rich at WOT anyway, will the ECU lean it out over time or will it be a short term fuel trim thing? Argh! LOL! I did not read about this in the 34,987,564 threads that I read!

Food for thought, bounce it off your tuner if you have one and see what they think. If I didn't have stupid big injectors for the boost I plan to run (anyone have some 440's to trade for 650's? lol) I'd likely have dumped the emanage already in favor of just the clamp and enricher.
Yesterday 09:14 AM

Tuner? That would be me :lol::lol::lol:

This is basically an educational project that I'm trying to do for under $2k ($1.5k US).

Thankyou for your help!

 

Now say I was to use the FMU (what a shame I spent forever reading up on them and finally found the perfect one that wasn't a fixed ratio ebay POS), what will the fuel trim effect be? I was under the impression that the stock ECU ran rich at WOT anyway, will the ECU lean it out over time or will it be a short term fuel trim thing? Argh! LOL! I did not read about this in the 34,987,564 threads that I read!

Fuel trims only get messed up if you boost during closed loop fueling. BUT, your closed loop fueling trims do affect WOT fueling. I think you'll be fine with the FMU, but watch your fueling pressures. I believe idle pressure is right around 40-45, so you only have 40-45psi to add before injectors start to fail. At 6psi of boost, your ceiling of FMU rise is 7.5:1. I think I've read success stories at 6:1 rise.

edit: My car crosses the boost threshold between 20-30% throttle, which is barely anything! So it's stupid easy to boost in closed loop, but that's where the Enricher device helps as it keeps the ecu from seeing the mixture richen.

Tuner? That would be me :lol::lol::lol:

This is basically an educational project that I'm trying to do for under $2k ($1.5k US).

You and me both friend! Though I wish my budget had been able to stay under 1.5k, LOL. I wish you luck! I had to buy two Emanage Ultimate's as the first one had a bum ignition controller. Those aren't cheap! I highly highly highly recommend an older laptop and a VAGCOM cable so that you can at least do a little bit of data logging with fuel trims to make sure it's all healthy.

I've seen a success story where they triggered the ECU to reset every time they turned the key on. This resets timing and fuel trim tables and lets you be more in control. Depending on the type of emissions you have where you live, it can cause a headache for that too as the car never completes its "emissions readiness" check.

that's the one most use for becuase of fitment issues with the stupid metal bugeye ones.

i'm pretty sure the actual from the factory turbo cars are different. this is just how we as NA-T'ers plumb it in.

Yeah, I use one with plastic end tanks. Think it's from an 06 or 07? Possibly newer, I really can't remember. Factory turbo cars have a separate coolant tank that sits on the passenger side of the intake manifold that the turbo is plumbed in to directly. I think I've read a couple posts where they use the throttle body coolant lines, but those are far far too small to be effective.

 

Fuel trims only get messed up if you boost during closed loop fueling. BUT, your closed loop fueling trims do affect WOT fueling. I think you'll be fine with the FMU, but watch your fueling pressures. I believe idle pressure is right around 40-45, so you only have 40-45psi to add before injectors start to fail. At 6psi of boost, your ceiling of FMU rise is 7.5:1. I think I've read success stories at 6:1 rise.

edit: My car crosses the boost threshold between 20-30% throttle, which is barely anything! So it's stupid easy to boost in closed loop, but that's where the Enricher device helps as it keeps the ecu from seeing the mixture richen.

Right. You have me a little worried. My Plan is to run 2-3psi and tune, then add boost gradually to 6psi and tune. I was tempted to buy an SS fuel module but the shipping to Australia is insane. I think I will get one but, I've spent a lot of money on a lot of things lately. Oops! Maybe I might find a used one for sale somewhere.

I have been looking at gauges for boost and AFR, I'm not a fan of having gauges hanging off of everything so I looked for a neat combination gauge. I have no trust in the cheap chinese gauges and they seem to be a pita to set up. The PLX website is having a black Friday sale, selling their OLED multi gauges and add on modules for a price too good to pass up. So I ordered a heap of stuff (in order to qualify for free international shipping and negate the near $200 shipping mg and I'll sell the extra stuff off.

I bought 2x DM-6 touch screen gauge and afr module combos, a boost/vac sensor and an egt module. :burnout:

You and me both friend! Though I wish my budget had been able to stay under 1.5k, LOL. I wish you luck! I had to buy two Emanage Ultimate's as the first one had a bum ignition controller. Those aren't cheap! I highly highly highly recommend an older laptop and a VAGCOM cable so that you can at least do a little bit of data logging with fuel trims to make sure it's all healthy.

I've seen a success story where they triggered the ECU to reset every time they turned the key on. This resets timing and fuel trim tables and lets you be more in control. Depending on the type of emissions you have where you live, it can cause a headache for that too as the car never completes its "emissions readiness" check.

Now, there is something funky about the AUDM cars before 2004 or so, they didn't run OB2 for some unknown reason. So I've tried a few readers including a VAG COM cable and could not get it to connect. I think it's ISO9194 or something.

Luckily we have no emissions testing here, but if the transport inspectors catch you without a cat in the exhaust you are in trouble.


Am I being delusional to think I can make this a reliable daily driver setup without stand alone ignition control on 6psi boost? I was convinced that it would be fine but now I'm not so sure. I'm a mechanically sympathetic person and look after all my stuff. If I hear a noise that ain't normal I investigate and fix immediately. I know some people just break everything they touch.

Also, nobody ever talks about fuel economy, do the cars tend to have similar fuel usage to stock when off boost? Currently I get close to 300miles city and 400 highway. I'm interested to hear results.

Again many thanks to you guys for the time you have put in to helping a turbo numpty.

 

Sounds like your gauges cost more than the whole car! But it looks like you have a solid setup. AFR, Boost, and EGT are musts for a turbo car. oil pressure and oil temperature are excellent to have as well. Those are the five gauges I run in my car.

You have a good plan with keeping boost low and tuning as you increase, but how do you plan to keep boost low? I think the lowest factory wastegate on a TD04 is 8 pounds. That is the maximum boost pressure at WOT. By using throttle control you can keep boost down but it gets tricky, because 3psi at WOT is going to need different fueling than 6psi at WOT. and your 3psi WOT fueling is going to be much different than your partial throttle 3psi fueling once you do turn the boost up. I was able to buy a 3psi wastegate on ebay, and I use an electronic boost controller to bring me back up to 8psi. Food for thought!

You're not being delusional, but if it's not OBD2 then you might have an easier time with this than we all think! But then I read this...

ISO 9141: Road vehicles — Diagnostic systems. International Organization for Standardization, 1989.
Part 1: Requirements for interchange of digital information
Part 2: CARB requirements for interchange of digital information
Part 3: Verification of the communication between vehicle and OBD II scan tool

Looks like it should be able to communicate over the obd2 port, can you confirm if there even is one? If it has an obd2 port I can only assume that it will have fuel trims, and those are necessary to log to make this a reliable car. VAGCOM would be ideal, but one of the ELM327 bluetooth jobbers on ebay should do the trick, though they don't refresh near as quickly.

The downside to "hearing noises that aren't normal" is how much quicker it becomes an issue once you're throwing several atmosphere's of air down the throttle body. My last motor popped due to the factory ECU advancing the timing too far while at 8psi partial throttle up a fairly serious grade... I heard a noise bouncing off the jersey barrier, the thought "what the f.." is all that managed through my head before the james bond mod enabled and I smoked everyone out on the freeway.

Fuel economy depends on how heavy your foot is. Your foot will be quite heavy for some time once the boost bug bites you. I was getting 18-20mpg, but also had evidence of nearing 30+mpg if I set the cruise at 60 on the freeway.

 

Sounds like your gauges cost more than the whole car! But it looks like you have a solid setup. AFR, Boost, and EGT are musts for a turbo car. oil pressure and oil temperature are excellent to have as well. Those are the five gauges I run in my car.

I spent $250 on my multigauge and 3 daisy chain modules with all the sensors and wiring harnesses to measure AFR/Boost/EGT accurately and somewhat graphically and accurately...and most importantly, neatly. I am not a big fan of stuff allover the dash .

You have a good plan with keeping boost low and tuning as you increase, but how do you plan to keep boost low? I think the lowest factory wastegate on a TD04 is 8 pounds. That is the maximum boost pressure at WOT. By using throttle control you can keep boost down but it gets tricky, because 3psi at WOT is going to need different fueling than 6psi at WOT. and your 3psi WOT fueling is going to be much different than your partial throttle 3psi fueling once you do turn the boost up. I was able to buy a 3psi wastegate on ebay, and I use an electronic boost controller to bring me back up to 8psi. Food for thought!

As far as low boost, I think I might need to find an aftermarket wastegate. Some can be changed a bit with an inbuilt turnbuckle and/or springs. I'll rig up a pressure gauge and play with the wastegate on the bench and see what is possible to do. As I said, I'm a turbo numpty.

As far as the tuning, what I mean is, I want to get the car all running nicely on 2-3psi. Drive for a week or so, iron out bugs etc, then richen the crap out of it and move to 6psi, tune and hopefully I will not wreck anything haha.

You're not being delusional, but if it's not OBD2 then you might have an easier time with this than we all think! But then I read this...

Looks like it should be able to communicate over the obd2 port, can you confirm if there even is one? If it has an obd2 port I can only assume that it will have fuel trims, and those are necessary to log to make this a reliable car. VAGCOM would be ideal, but one of the ELM327 bluetooth jobbers on ebay should do the trick, though they don't refresh near as quickly.

It's weird, it has the OBD2 plug, but it apparently is OBD1 or something. Some Australian quirk. I've tried 3 OBD2 readers, a blue VAG COM cable, and ELM327 bluetooth one and another one I borrowed. None worked, but they can plug it in at the dealership and read things. Perhaps I need to do more research, or perhaps the pinouts are different...who knows!

The downside to "hearing noises that aren't normal" is how much quicker it becomes an issue once you're throwing several atmosphere's of air down the throttle body. My last motor popped due to the factory ECU advancing the timing too far while at 8psi partial throttle up a fairly serious grade... I heard a noise bouncing off the jersey barrier, the thought "what the f.." is all that managed through my head before the james bond mod enabled and I smoked everyone out on the freeway.

This paragraph actually gave me a cold sweat and almost made me reconsider doing this conversion. The only way I can see myself getting around this without full on engine management is by installing a J&S safeguard. There must be heaps of these floating around second hand...

Do you have any other suggestions, bearing in mind I will be running less boost and 92+ octane fuel?

 

Subaru has their own protocol try a vagcom cable and this program FreeSSM - Complete access to your ECM and TCU - Subaru Outback - Subaru Outback Forums

I think the only thing you're missing is a way to control timing.

 

I did try this too, but I had n luck, perhaps I did something wrong. It would be nice to be able to log stuff.