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2017 VW Golf SportWagen 5MT
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You'd have to come up with an engine management system too, and figure out how to increase amount of fuel when getting on boost. Even then, you wouldn't be able to run more than 6psi or so (10:1 compression ratio). This is without an intercooler cost, too. Not saying it can't be done, it just isn't cheap. It'll be laggy too since the air from the turbo has to travel the length of the car.

Saw this in our work parking lot a couple of years ago, it was AWESOME:





Stan
 

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2007 FXT vf37 swapped 4EAT w/ VDC
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They claim there's not that much lag since the system reduces heat soak, and the return piping acts as an intercooler.
 

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2017 VW Golf SportWagen 5MT
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Just looked again at what comes with the kit and I can't figure out what they are charging 2k for. A chinacharger is $200-$300 what costs the other $1,700?

You could do the same kit yourself alot cheaper if you have fabrication skills. But, I would not dare do this to a new car.

Stan
 

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2001 SOLD!
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:huh: What turns the turbine is heat. Once it reaches the rear of the car it has cooled down and lost expansion. Also under the car like that. On a rainy day or salt covered roads I get here in the winter, it wouldn't last long.
 

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Discussion Starter #7
I understand the naysayers... but here are my points of discussion...
The theory of this type of system makes sense to me and im open for your intelligent ideas. Im no efi tuning/turbo guru but if you are feel free to chime in...
1. Air:
The exhaust gases have to reach the turbine to spool it, be it cooler/hotter, whether is 5 ft of header tubing or 10 ft downstream. You could heat wrap the exhaust if youre worried about loosing that much velocity, besides cooler turbo temps equal longevity right?
Seeing all the piping involved in say a FMIC setup would just about equal the length of the STS setup give or take a foot so lag would be relative...
2. Turbocharger:
If you were to DIY, this is where you could pick your ideal turbo to give you the proper size per application needed. I dont think youd want anymore than 6-8 psi on a NA motor in the first place so normal low RPM driveability would be desired over top end track car prowess...
3. Fuel/Tuning:
Now for me,this is where it gets tricky....couldnt you just use a RRFPR along with some piggy back system? plug in a like MY XT Ecu and tune from there...Im just shooting out ideas. Add some meth/water injection to be safe with pump gas....
4. Engine damage:
Im sure if you go crazy boosting any 2.5NA motor something is gonna fail...but I have an engine and tranny for life guarantee when I bought my car....not saying If I overboosted my engine and killed it I would just unbolt all the parts and tow it to the shop, but you never know....:icon_wink:
 

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2004 Forester 4EAT
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There is a twin turbo setup for corvettes that adds something like 100 hp. Turbos go behind the rear wheels. Looks bada$$ from the rear.
 

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2017 VW Golf SportWagen 5MT
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I'm not saying it wouldn't work, I'm just saying "why go this route"? There is room in the Subaru engine bay for a turbo and you can use a FMIC if you wanted to.

In the end, it would be easier and more reliable to transplant a WRX engine into the car. It's one thing when you boost an N/A engine that was built for boost to begin with (like in the Miata), boosting a Subaru N/A engine just isn't as ideal.

It could be a cool project though.

Stan
 

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2001 SOLD!
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^ i though the turbo spooled up based on pressure, not on heat ... can anyone verify this
What I meant is hot gases. On my Cummins I am boosting 40 p.s.i because my EGT's went from 750 deg F to 1100 deg F:icon_wink: So easy to bump up the fuel on those 12V Cummins!!!:rock:

More fuel + More hot gases= Higher boost.:lildevil:
 

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SG9 Forester XT Stick Shift
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That universal system are not complete. They are still missing most of the piping and engine management still need to be taken care.

STS turbo are not normal turbo. Theoretically they need to have smaller hot side to compensate for colder exhaust but bigger compressor turbine ratio than normal turbo application. If you could marry a 8cm compressor housing to a TD04 turbine that might work for this application.

Converting an XT might be interesting and might be cheap since you do not have to buy expensive turbo and intercooler.
 

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2009 Outback XT-B 5MT
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I understand the naysayers... but here are my points of discussion...
The theory of this type of system makes sense to me and im open for your intelligent ideas. Im no efi tuning/turbo guru but if you are feel free to chime in...
1. Air:
The exhaust gases have to reach the turbine to spool it, be it cooler/hotter, whether is 5 ft of header tubing or 10 ft downstream. You could heat wrap the exhaust if youre worried about loosing that much velocity, besides cooler turbo temps equal longevity right?
Seeing all the piping involved in say a FMIC setup would just about equal the length of the STS setup give or take a foot so lag would be relative...
Hot air has more energy. More energy means higher velocity. Higher velocity means faster spool. Cooler charge air means slower spool. You have the same volume of air getting to the turbo, but it's cold and slow by the time it gets there. Poor response is the recipe you are following. Subaru made a significant effort to reduce pre-turbo piping on the '10 LGT to the result of MUCH improved spool. Short exhaust before the turbo is fact for having high response.

2. Turbocharger:
If you were to DIY, this is where you could pick your ideal turbo to give you the proper size per application needed. I dont think youd want anymore than 6-8 psi on a NA motor in the first place so normal low RPM driveability would be desired over top end track car prowess...
You would need a REMARKABLY small turbine side to compensate for the lack of exhaust velocity. A turbine that small isn't going to be capable of spinning a compressor large enough to efficiently fill the charge pipe and force air to the motor. The "small turbine big compressor" idea falls on its face. There is more to turbo sizing than that.

3. Fuel/Tuning:
Now for me,this is where it gets tricky....couldnt you just use a RRFPR along with some piggy back system? plug in a like MY XT Ecu and tune from there...Im just shooting out ideas. Add some meth/water injection to be safe with pump gas....
Not as easy as that, if you want it to be reliable, but you CAN use a PP6 and an RRFPR if you want to ghetto it into working, and not optimize power.
4. Engine damage:
Im sure if you go crazy boosting any 2.5NA motor something is gonna fail...but I have an engine and tranny for life guarantee when I bought my car....not saying If I overboosted my engine and killed it I would just unbolt all the parts and tow it to the shop, but you never know....:icon_wink:
Remote turbo mounting on a small displacement motor isn't going to do a lot. I would rekon a guess that you wouldn't be able to produce more than 3 or 4psi using a turbo that provides even modestly respectable spool. It just wouldn't be worth it.

I actually know a guy with an STS turbo kit on his 6.0L GTO. It works. Because it's got 6-liters feeding exhaust gas down stream. It's laggy, and on a 70-trim (which is a MASSIVE turbo), it only makes around 7psi, but it was good for what the guy wanted to do (not supercharge the car).

On a small displacement motor, you really don't have the volume OR velocity to take full advantage of a setup like this. Your best bet is to build a custom uppipe, and put a stock turbo in the stock location and go from there. You'll end up with a more reliable setup that has better rewards. Bobby has one of the very few AVO kits on his son's car, and AFAIK it has been quite reliable for YEARS.

Put a turbo under the boot, and you'll regret wasting your time and money. It'll be MUCH more work than building a custom up-pipe and downpipe for WAY worse results. Get a stock WRX TMIC and a TD04, build a custom up-pipe and downpipe, and tune it. Problem solved.
 

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Discussion Starter #13
cool. Thats the kind of opinion I wanted. All that does make sense. Its tempting to want to bolt on some power adders and with my car being 4 months old, Im not swapping motors anytime soon. Thanks for the advice:icon_cool:
 

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2005 Forester XT
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when I worked at a certain shop these guys tried to convince me that their systems worked better than the conventional method, which I thought originally was total BS at which point I lost interest... There is a silverado ss truck here in vegas owned by Adams Driveline that from what I'm told is a 10 second vehicle on e85 with a single rear axle mount sts turbo..so...
 

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2009 Outback XT-B 5MT
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Think of how much faster it would be with an underhood turbo!

That GTO I mentioned before makes MUCH less power than a Magnacharged GTO of the same displacement, with MUCH worse drivability.
 
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