I would like to know if there's anyone who have done the 'parallel fuel rail' mod N/A or turbo'd. I was thinking of doing this mod because the Subaru techies stated that the 3rd chamber runs lean because of the way the fuel flows (in series). This will, if not fix, give the same amount of fuel to each chamber. Performance? Lowers fuel usage? I would like to know the stories behind it. Thanks.
DIY Paralleling fuel mod
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Well, I did it to my car, though you could call my version anything but parallel. To understand what I did, and you really have to understand flow techniques, you would have to see a picture. Basically, instead of cutting away all the fuel lines and replacing them all, all you have to do is ADD a fuel line.
Where the fuel line coming from the tank enters through the firewall (line with a blue beginning), you will want to focus on this line as your main source of getting fuel to cylinder #3. Cylinder #3 is on the left side and runs approximately 8 psi less of fuel pressure (stock) than the other cylinders. To combat this, all that needs to be done is add more fuel.
Follow the fuel line into the car, and about a foot in it will become a rubber fuel line. All you have to do is cut this line (3/8") and run about a three-four foot piece of fuel line to the fuel rails on the left side (#1, #3). Where the fuel in line comes to the passenger side fuel rails, you will see a piece of rubber hose, and this must also be cut and a brass T fitting, with 3/8" all the way around.
I really don't have the time to expain this right now, but I will tomorow, so stay tuned.
Graham
Where the fuel line coming from the tank enters through the firewall (line with a blue beginning), you will want to focus on this line as your main source of getting fuel to cylinder #3. Cylinder #3 is on the left side and runs approximately 8 psi less of fuel pressure (stock) than the other cylinders. To combat this, all that needs to be done is add more fuel.
Follow the fuel line into the car, and about a foot in it will become a rubber fuel line. All you have to do is cut this line (3/8") and run about a three-four foot piece of fuel line to the fuel rails on the left side (#1, #3). Where the fuel in line comes to the passenger side fuel rails, you will see a piece of rubber hose, and this must also be cut and a brass T fitting, with 3/8" all the way around.
I really don't have the time to expain this right now, but I will tomorow, so stay tuned.
Graham
I don't wanna sound lazy, but I just don't wanna literally crawl into my engine bay and mess with the wires. I wouldn't wanna pay for cutting something wrong or loosing some bolts, etc. I wanna try out Graham's technique. I just have to get a good picture of the fuel system in my head. Actually, I don't know how the fuel flows and the path of the flow from the tank to the cylinders. Any help? Thanks.
Thanks for the good response guys. As far as having this done by a tuning shop, don't waste your money. The intake manifold needs to be removed, though this is of the utmost simplicity. All that needs to be removed are eight bolts that hold the intake manifold on, along with unplugging all the wiring harnesses and what not.
If you follow the directions from Ravensblade, but only to a certain point, you can complete this with ease.
http://www.ravensblade-impreza.com/index1.html
Basically you just want to follow the instructions up until the intake manifold has been removed. After this, it would be my write up of directions.
The tools you need are listed on the site, and the instructions do a great job up until the time of re-arranging the fuel lines. This is where I stopped, thought for about two hours, and decided to do it my own way (with the help of my father and uncle who are petroleum engineers, and masters of flow design).
Don't get me wrong, the parallel way works, but for the 00-01 MY cars, there is something missing, at least there was for me.
James, I would be happy to do a write-up of this install, with proof that it works, if you want to put it up on the sight. My only problem is, I am pretty much illiterate when it comes to putting stuff on the internet (i.e. pictures and html documents). I can write it up on MS Word, then email it to you?
If not, I will just post up the directions on this thread and let it be, and I'll have to get a friend to help me with the pics.
I can have the complete install up within two days, if you guys can wait, and it will be very precise and detailed, unlike the some OTHER directions.
Graham
If you follow the directions from Ravensblade, but only to a certain point, you can complete this with ease.
http://www.ravensblade-impreza.com/index1.html
Basically you just want to follow the instructions up until the intake manifold has been removed. After this, it would be my write up of directions.
The tools you need are listed on the site, and the instructions do a great job up until the time of re-arranging the fuel lines. This is where I stopped, thought for about two hours, and decided to do it my own way (with the help of my father and uncle who are petroleum engineers, and masters of flow design).
Don't get me wrong, the parallel way works, but for the 00-01 MY cars, there is something missing, at least there was for me.
James, I would be happy to do a write-up of this install, with proof that it works, if you want to put it up on the sight. My only problem is, I am pretty much illiterate when it comes to putting stuff on the internet (i.e. pictures and html documents). I can write it up on MS Word, then email it to you?
If not, I will just post up the directions on this thread and let it be, and I'll have to get a friend to help me with the pics.
I can have the complete install up within two days, if you guys can wait, and it will be very precise and detailed, unlike the some OTHER directions.
Graham
G
Guest
·:drool: :drool: :drool:
Write it up in Werd.
Send it to James.
email him the photos.
Or maybe I'll just start cutting stuff on my engine.
Write it up in Werd.
Send it to James. email him the photos.
Or maybe I'll just start cutting stuff on my engine.
Sweet, can't wait to see this! I'm not sure if I'm going to do it yet (car still has a bit of warrenty on it), but if (when) I go FI, this will need to be done. Hell, even if I don't go FI, I'm going to do this when the warrenty expires.
G
Guest
·Of course unless you've got a problem that requires them to pull the intake manifold, no?Graham said:
Well, maybe, though the mod looks so stock it might be hard to tell. All your adding is a 3-4 ft long piece of fuel line, and two brass T fittings. Its a very simple process. If you have a fuel pressure gauge, let me know if you notice anything different after you do the install...your fuel pressure should be a few psi less, meaning your consuming more fuel, and cylinder #3 is no longer running leaner than the other.
Graham
Graham
Yes, and I should be able to get to it this weekend and post it for all to see. However, due to family issues I am still too busy to do it for a few days.2Point5RS said:
And I'll start changing Scooby of the week again, too! :biggest:
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