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where do I get the "real cap" ? Complicated or easy to do like this?... JOIN NOW TO REMOVE TRACER

Capping A Fuel Rail

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Old 08-16-2008, 07:07 PM
Diesel Enthusiast


where do I get the "real cap" ? Complicated or easy to do like this?
Old 08-16-2008, 11:25 PM
Red_Rattler's Avatar
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Jacob Boness

Or you could just get the dual fuel line kit.....

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03Flame Red 2500 4x4 QuadCab Handshaker HO,Kore HP Kit, Smarty REVO, AIRDOG II 165, Banks TechniCooler, K&N FIPK, MBRP Cool Duals 6inch tips, GunSlinger Pistol Grip Shifter, SRT Inine 6 Hood, Jacobs Brake

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Old 08-17-2008, 01:25 PM
Diesel Fan



Floor It sells the cap that takes the place of the relief valve fitting. very nice piece. the dual feed line kit doesn't really do much for performance, but it will act to cap the rail.
Old 09-10-2008, 01:53 PM
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Got her plugged. Just so everyone knows, need a 3/8 FT(24 tpi) tap and 3/8 24tpi set screw.

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2004.5 bright silver reg cab 2500 600 CTD "Stock but it smokes a little and goes fast"
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Old 09-10-2008, 02:15 PM
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Being Twisted In the Wind

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Appreciate the re-loc!!!

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2006 Ram Cummins

Old 11-06-2008, 09:30 PM
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Right, need a fine thread tap. But which size plug? 1/8" or 3/8"? I forgot when I did mine.

Last edited by wildbill; 11-06-2008 at 09:32 PM.
Old 11-09-2008, 09:51 PM
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What is this mod for? Im

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Old 11-19-2008, 06:28 PM
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Originally Posted by dieselgrl4life View Post
What is this mod for? Im
Wow, you're alive after all.

It keeps fuel from returning over relief--the valve will open but no fuel can get out so it'll continue to keep the rail pressurized.
Old 11-25-2008, 09:49 AM
Diesel Fan



Ok, stupid question. I can see the possible damage that might happen if you cap the rail and it keeps hitting the roof. Something has to give somewhere.

I can understand that if it is capped and it keeps the rail pressurized, you will keep the fuel in the rail compared to draining back through the relief valve when you are in a WOT situation.

But, my truck is basically still stock (2005) except with RokkTech Sensor to advance timing, slightly better airflow (not aftermarket), RokkTech muffler and a somewhat heavy right foot now and then. Would this benefit me since I really don't have a guage to see what my current fuel pressure is when going down the road or even WOT? Would I feel it with my SOPG (seat of pants gauge)?

102,000 miles on truck so I don't really want to blow the thing up but always looking for a better performance mod if possible. Yes, some day I would like to purchase Smarty and all the guages that I currently don't have, but in the mean time. As long as it wouldn't blow it up upon first WOT, should I be fine?

How would I tell if something was starting to go bad due to this mod? Popping noise, damage to injectors, anything like that?

Worse case is take it back out.

Just asking. Thanks. Scott

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2005 2500, Smarty POD, Arson III CP3, Pro-Guard 7 Air Filter, Swiss Cheese airbox with Ram Snorkel, Chromed Torque Tube, Silencer Ring MIA, Tone Ring modified, Pryo, Boost, LED Trans temp gauges, TC Lockup Switch, Rokktech Sensor, Rokktech Muffler, BF Goodrich M/T KM2 on stock chrome rims. GONE. Truck was a good truck.
Old 11-25-2008, 01:27 PM
Mr. Miyagi's Avatar
Diesel Bomber
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I'm no 3rd Gen guy but I think this mod only benefits those who have upgraded their fuel delivery system to the point where the engine demands exceed the system's factory limits.

Maybe...just guessing here.

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rail cap vs. dual feed line - Page 2 - Competition Diesel.Com - Bringing The BEST Together This thread Refback 04-03-2009 09:50 PM
Hard Starting. - TDR Roundtable This thread Refback 10-05-2008 08:18 PM

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