FRx
Senior User
Joined: Mar 2007
Posts: 473
Likes: 3
From: Issaquah, WA
It connects the two fuel rails together to better feed cylinder #8 fuel. The firing order ends in 6 then 8. 8 is next to 6 and at the end of the fuel header. 8 geats starved for fuel, which is why it has a special injector in. Fords difficult way of trying (and failing) to fix an easy problem.. The FPx may also have an air bleed feature to improve fuel charactersitics at the injector. The FPx is much like a poor man's regulated return.
Elder User
Joined: Nov 2004
Posts: 684
Likes: 1
that makes sense.
I was told when doing the "buzz" test that the #8 will sound different, but he told me the reason was to be "quieter" since it was closests to the driver. he didn't mention anything about a fueling issue?
I was told when doing the "buzz" test that the #8 will sound different, but he told me the reason was to be "quieter" since it was closests to the driver. he didn't mention anything about a fueling issue?
Lead Driver
Joined: Jan 2006
Posts: 7,308
Likes: 250
From: Hartford, WI
I don't think they even understand what is going on. #8 is a different injector. You have 7 ADs and 1 AE. The AE is the long lead injector inserted because customers complained about a cackling noise. Band Aid fix when it should have just tied the heads together.
Lead Driver
Joined: Jan 2006
Posts: 7,308
Likes: 250
From: Hartford, WI
Sinister Diesel 7.3L "Standard" Regulated Return Kit
Diesel Innovations regulated fuel return kit
I have the DI kit. At the time, I didn't know if the SD kit would fit the dual oil pumps so I bought the DI kit. SD kit looks sexier and has braided hose so you don't have to worry about something cutting the fuel line.
Hotshot
Joined: Jul 2003
Posts: 12,177
Likes: 40
From: Newport, WA
Regulated return systems can be had with a fuel bowl delete, or to work with the stock bowl. Sinister Diesel (formerly ITP) is one of the more popular choices.Edit- aklim has faster fingers than me.
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Lead Driver
Joined: Jan 2006
Posts: 7,308
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From: Hartford, WI
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Posting Guru
Joined: Dec 2009
Posts: 2,265
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From: Garden City, KS
I did it on my truck and was able to utilize my fuel bowl... it was a complete regulated return. I'll write a thread about it here as soon as I've got time... the pictures are already uploaded to Picasa!
Posting Guru
Joined: Dec 2009
Posts: 2,265
Likes: 2
From: Garden City, KS
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