Anybody want to explain fuelrail drain?
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From: LaGrange, Texas
Anybody want to explain fuelrail drain?
I've been reading alot of threads concerning rail drain in higher hp apps. I just basically want to start a thread with some bona-fide talk about this subject.
When does this usually become a problem?
Why?
I know...
What has been the best solution?
When do I need to worry about draining the rails?
And I know modding is fun and I plan on alot of it, but is there a "best" order to start with when it comes to what is needed the most?
When does this usually become a problem?
Why?
I know...What has been the best solution?
When do I need to worry about draining the rails?
And I know modding is fun and I plan on alot of it, but is there a "best" order to start with when it comes to what is needed the most?
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From: Twin Falls, Idaho
A modded cp3 is the first answer to help or dual cp3's.. Draining is when your cp3 can't keep enough fuel in the rail that feeds the injectors thus running it dry.. I think... I am no means a cummins pro and others will chime in but that is what I consider "running dry" means. You can also get II's new dual feed line but it removes the relief valve so there is pro's and con's to that but Relentless has built a dual bypass valve that run's the dual feed line and keeps the relief valve.. I have the dual feed line right now just waiting to hear on the valve!!
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From: LaGrange, Texas
Now I've seen some very expensive cp3s. I don't really want to exceed 500hp (hit it maybe) so how much would I be looking at for one?
And what would it feel like if the rail was running dry? Does it get sluggish, maybe egt increases? I'm just trying to get a basic understanding because from what I've seen, fuel issues are more important than I imagined.
And what would it feel like if the rail was running dry? Does it get sluggish, maybe egt increases? I'm just trying to get a basic understanding because from what I've seen, fuel issues are more important than I imagined.
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From: Twin Falls, Idaho
Now I've seen some very expensive cp3s. I don't really want to exceed 500hp (hit it maybe) so how much would I be looking at for one?
And what would it feel like if the rail was running dry? Does it get sluggish, maybe egt increases? I'm just trying to get a basic understanding because from what I've seen, fuel issues are more important than I imagined.
And what would it feel like if the rail was running dry? Does it get sluggish, maybe egt increases? I'm just trying to get a basic understanding because from what I've seen, fuel issues are more important than I imagined.
http://relentlessdiesel.com/forum/viewtopic.php?t=19
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From: Houston, TX
Well you do not need a cp3 upgrade to hit 500hp. I have been over 500hp for a good while now. If I set boxes/downloader to the 500-525 range I do not loose rail pressure on the track. If I set higher than that I do loose rail pressure on the track. It will definitely be specific on the types of mods/settings on when the stock cp3 can't keep up. I would guess bigger injectors may cause this at lower hp ratings, but I still have stock injectors so not sure.
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From: LaGrange, Texas
I figured my stock injectors would hold up, but wanted to upgrade to a fass so I can turn my smarty up and not be AS worried, con fe sbc clutch, and maybe an aurora2k. I just don't want to get into a trouble range because it is running so good. I just wanna help it out a bit. I just don't know what I should do first because I can't do them all at once, and I just wanna learn more about the fuel system and what triggers the most problems. I wanna UNDERSTAND lol!!!
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From: Houston, TX
rip 112
Do you have a fuel pressure gauge?? The Smarty, at least the non beta ones I have ran do not increase the max rail pressure. Or at least not enough for me to see.
As long as you have EGT and Boost gauges to keep from nuking something I would do the clutch and turbo first. With the Smarty alone you can probably wait on the lift pump until later. That is just my opinion and carries no expert level of knowledge.
Do you have a fuel pressure gauge?? The Smarty, at least the non beta ones I have ran do not increase the max rail pressure. Or at least not enough for me to see.
As long as you have EGT and Boost gauges to keep from nuking something I would do the clutch and turbo first. With the Smarty alone you can probably wait on the lift pump until later. That is just my opinion and carries no expert level of knowledge.
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From: LaGrange, Texas
I don't have a RP gauge, but i was aware of the smarty and no pressure, I just figured it has to be dumping more fuel somehow. So I guess the clutch is naturally first because mine can barely handle sw7, then the turbo. Is the aurora2k a good choice, or would you suggest another? Thanks for the help. if anyone else cares to chime in, much is appreciated.
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From: Idaho Falls & Southern CA
I ran 605 on stock CP3 and injectors for a while. It doesn't last that long. you are basically just waiting to break at that point. For 500hp though I would think that a modded CP3 would work. If I had to do it again. I wouldn't waste the money on a modded pump though. I would go with a stage 3 pump for sure.
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From: LaGrange, Texas
Thanks for the info. I want my truck to make that power comfortably so I don't have to have it maxed out. Would a fass system be the ticket, or are there better/cheaper/dependable systems? And what size, 150gph?
