Which fuel pressure spring?
FTE Remembers
Joined: Nov 2007
Posts: 9,549
Likes: 14
From: Payson, AZ
Do you have a fuel pressure gauge?
I went with the black spring when I installed Dieselorings FPR Billet
housing and the KOEO or idle pressure is 70-71 PSI. 65 psi at WOT.
From Riffraff FRx page.
I went with the black spring when I installed Dieselorings FPR Billet
housing and the KOEO or idle pressure is 70-71 PSI. 65 psi at WOT.
From Riffraff FRx page.
55-60 psi silver spring
61-65 psi gold spring
66-72 psi black spring
61-65 psi gold spring
66-72 psi black spring
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Tuned
Joined: Dec 2008
Posts: 373
Likes: 5
From: Evergreen Colorado
What are some of the determining factors in deciding how much fuel pressure I need?
Throttle position I mostly drive at? Mods?
This is my first time diving into the diesel fuel system.
FTE Remembers
Joined: Nov 2007
Posts: 9,549
Likes: 14
From: Payson, AZ
Be certain you get the spring in properly. If it is cocked, and that is easy to do, the fuel pressure can reach or exceed 100 PSI. I personally don't like to mess with the FP springs unless I can read the FP to be sure the spring is not cocked.
When installing the FRx is a good time to do an FPR rebuild. LINK
Thread Starter
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Tuned
Joined: Dec 2008
Posts: 373
Likes: 5
From: Evergreen Colorado
WOT pressure is the determining factor. That is why it is nice to have a FP gauge you can read while driving. WOT 50+ psi would be good with stock injectors. Like Roland said the gold spring would be a good start until you have a FP gauge. Keep track of that black spring. You may want to use it if/when you upgrade injectors.
Be certain you get the spring in properly. If it is cocked, and that is easy to do, the fuel pressure can reach or exceed 100 PSI. I personally don't like to mess with the FP springs unless I can read the FP to be sure the spring is not cocked.
When installing the FRx is a good time to do an FPR rebuild. LINK
Be certain you get the spring in properly. If it is cocked, and that is easy to do, the fuel pressure can reach or exceed 100 PSI. I personally don't like to mess with the FP springs unless I can read the FP to be sure the spring is not cocked.
When installing the FRx is a good time to do an FPR rebuild. LINK
How would I know without a gauge if I put that spring in crooked.
I also rebiult the entire fuel bowl including the FPR.
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I use a stock spring, but I did drill out my brass head plugs with a 1/4 bit for less restriction while hot. I have 62 - 63 psi's at idle and WOT.
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