LLY: Why use a RACE FUEL VALVE

[Hahns069]

Hello I'm kind of new to this forum thing. My son bought a PPE Race Fuel Valve for my LLY. I'm Try to understand why I would need to install this in my truck. What would be the benefit of installing this? Also what is the down side using this Fuel Valve plug. Will it damage anything? Does it make more horse power? I get kind of nervous messing with the stock items in the truck. If anyone out there can shed a little light of info on me.
Thanks again................

 

[WolfLMM]

Keeps rail pressure up. Factory valve can be weak and allow fuel to leak to the return side, thus causing low rail pressure during power enrichment. It's a safe mod.

 

[D1rty-max]

Does away with the relief valve which can pop open at higher rail pressure it won't hurt a thing installing it! The stock valve gets weak after popping a couple times it should help fix low fuel rail pressure codes if you are having issues with the stock relief valve opening

 

[Chevy1925]

the plug goes in place of the fuel pressure relief valve. on 04.5-10 trucks, the fuel pressure relief valve (FPRV for short) has a tendency to pop open when running larger tunes or higher demanded fuel rail pressure. once it pops, it becomes very easy for it to pop again and again even on a stock tune. There is a test that can be performed called a "bottle test". do a search on here and it will explain that.

the plug effectively stops the issue as it replaced the FPRV but you no longer have a "safety device" to protect injectors or the CP3 from too high a rail pressure and hurting parts. in all the years ive played with these trucks ive only seen a handful of trucks have issues from a rail plug and it was back in the day when people were mixing larger cp3's with stock CP3s and not tuning things correctly or hard parts just were prone to fail from bad casting, etc. i run a race valve in my truck though.

so it wont make HP, it just makes sure you get all the power you could have

 

[NinjaMax]

and it sucks balls to get the fprv out...on an epic level...

 

[LBZ]

http://www.duramaxdiesels.com/forum/showthread.php?t=267

Sent from my D5803 using Tapatalk

 

[LBZ]

Personally I would just shim the factory valve and save my money.

Sent from my D5803 using Tapatalk

 

[Chevy1925]

Personally I would just shim the factory valve and save my money.

Sent from my D5803 using Tapatalk

ive welded the hole shut on the back side of the fprv before. use it as a test plug to see if the race plug is leaking due to a bad seal on trucks. ive contemplated just welding them

 

[zf>allison]

Mine was welded on the crew cab, I think it's safer to have a plug than loosing rail pulling out in traffic or passing someone for sure.

 

[Ne-max]

Most guys throw them on hoping it fixes a rail issue caused by bad injectors. Usually start with rail plug. Then lift pump the trucks for sale. I have only had 1 test out bad in the last 4 years. Then fought getting race plug to seal.

 

[Dozerboy]

I like a little safety factor on a street truck. A truck could become a fire ball real fast if you split something in the fuel system. And injectors aren't cheap if you overpressurized them.


Sent from my iPhone using Tapatalk

 

[IOWA LLY]

I like a little safety factor on a street truck. A truck could become a fire ball real fast if you split something in the fuel system. And injectors aren't cheap if you overpressurized them.


Sent from my iPhone using Tapatalk

I totally agree with this statement, however, I honestly don't believe that the pump is capable of making enough pressure to burst anything.

I've tried my share of stupid things, and had some problems over the years on various trucks that caused some wicked high rail pressures, but have never broke anything on an LLY and newer fuel system from to much pressure.

I install a ton of race valves. Never once had an issue. But there is a trick to installing them.


Sent from my iPhone using Tapatalk Pro

 

[zf>allison]

I bet I spike pretty high rail going from a fully loaded engine, then just stab the clutch and shift and never let off the throttle. I bet it spikes up pretty good. On the other hand I've never ran dual fuelers, but will be soon.

 

[Chevy1925]

If you split a line, there won't be anything being sprayed anywhere, MABEY for a split second but nothing but a dribble after that and an engine about to die off cause of it. It would have to be a hell of a tiny hole or split to make it spray with any kind of pressure and I've yet to ever hear of anyone have that happen. The pumps just don't have the volume

 

[Ne-max]

Isn't Mark running 30k plus rail on some of his builds?

 

[IOWA LLY]

Isn't Mark running 30k plus rail on some of his builds?

I've ran over 34,000 on competition only stuff.


Sent from my iPhone using Tapatalk Pro

 

[JoshH]

Most guys throw them on hoping it fixes a rail issue caused by bad injectors. Usually start with rail plug. Then lift pump the trucks for sale. I have only had 1 test out bad in the last 4 years. Then fought getting race plug to seal.

Yep. I have seen a bunch of true LLY trucks pop them, but when they upped the max rail pressure with the LBZ, they also raised the pop pressure on the relief valve. The only time I have ever seen an LBZ or LMM pop a relief valve is on a truck running a dual CP3 setup. Most people usually install a race valve on an LBZ or LMM because they think or they heard it is a problem. Unless you have verified your valve is leaking or you have an 04.5-05 LLY, you are most likely wasting your time by shimming or installing a race valve.

 

[zf>allison]

Yep. I have seen a bunch of true LLY trucks pop them, but when they upped the max rail pressure with the LBZ, they also raised the pop pressure on the relief valve. The only time I have ever seen an LBZ or LMM pop a relief valve is on a truck running a dual CP3 setup. Most people usually install a race valve on an LBZ or LMM because they think or they heard it is a problem. Unless you have verified your valve is leaking or you have an 04.5-05 LLY, you are most likely wasting your time by shimming or installing a race valve.

lly's are bad
My brothers lly I just bought was popping his with a hundred hp tune when he bought it.

 

[Chevy1925]

Yep. I have seen a bunch of true LLY trucks pop them, but when they upped the max rail pressure with the LBZ, they also raised the pop pressure on the relief valve. The only time I have ever seen an LBZ or LMM pop a relief valve is on a truck running a dual CP3 setup. Most people usually install a race valve on an LBZ or LMM because they think or they heard it is a problem. Unless you have verified your valve is leaking or you have an 04.5-05 LLY, you are most likely wasting your time by shimming or installing a race valve.

Kinda like the lb7. They don't pop but once they do (if ever), they damn near never seal again

Honestly, I wish the made set pressure ones like the cummins boys can get. Shimming it doesn't do a thing to tell you where it will pop and most guys set it to the point of spring bind or just before so it won't ever open. Or maybe they do and I just ain't looked yet

 

[Harbin_22]

I think it's funny when people try a race valve to help low rail without doing the super simple bottle test.