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Race Valve...

10K views 74 replies 32 participants last post by  jc1843 
#1 ·
I got an Alligator Performance race valve for Christmas. After reading about it now that I have it, I think I should have put a shim kit instead of a race valve. But seeing that nothing bad has really happened with race valves, I plan on just going ahead and putting it in. I was wondering if I was gonna have to put an o-ring or a washer on it? My girlfriend's Dad who is a mechanic told me I'm gonna have to but since it didn't come with one I was thinking maybe not. Anybody know what I should do? I rather be safe than sorry.
 
#3 ·
You can reuse the o ring on the fprv or just get a new one from local autoparts store. Super easy job. I tried the shim kit first and ended up doing the race valve.
 
#5 ·
Make sure to get it tight it's suppose to be something like 75ft/lb I was told
 
#10 ·
A new 18mm, i used a tired one and stripped mine. Ended up pulling the fuel rail.
 
#8 ·
I bought the shim kit... Played around with it... Couldn't get the valve off, so I bought a race valve as I started to round off my stock valve with impact 6 point sockets.. No clue how... Continuously tried every other day taking on and off the glow plug controller... Got pissed at it, drilled a hole in the top of it so I could finally reach the bolts underneath it with ease... Tried some more.. Rounded it more.. Ended up keeping the glow plug bracket off, zip tieing it up somewhere where it held tightly.. Tried more every other day, more rounding.. Got a viper security system installed at Best Buy and the dude put the siren right where my bracket was suppose to be mounted but it was zip tied out of the way... AWESOME... Probably going to have to rip my rail off to finally get it in. I still have yet to succeed. Ha. My opinion would be to throw either one in there if you can get it in. Beward it is tightened by the hand of GOD. ha
 
#20 ·
I bought the shim kit... Played around with it... Couldn't get the valve off, so I bought a race valve as I started to round off my stock valve with impact 6 point sockets.. No clue how... Continuously tried every other day taking on and off the glow plug controller... Got pissed at it, drilled a hole in the top of it so I could finally reach the bolts underneath it with ease... Tried some more.. Rounded it more.. Ended up keeping the glow plug bracket off, zip tieing it up somewhere where it held tightly.. Tried more every other day, more rounding.. Got a viper security system installed at Best Buy and the dude put the siren right where my bracket was suppose to be mounted but it was zip tied out of the way... AWESOME... Probably going to have to rip my rail off to finally get it in. I still have yet to succeed. Ha. My opinion would be to throw either one in there if you can get it in. Beward it is tightened by the hand of GOD. ha

Yes, those FPRV's are on there super tight but I was able to get a 3/8" impact gun (need something with some oomph so an IR2112, IR2115 or similar should work fine) with an 18mm swivel impact in there and it came off after failing multiple times to get it out manually. Remove the GP bracket, crank up the air pressure to 120 psi and tighten the valve with the gun first, then use reverse to see if you can't get it to break loose. Even rounded off I bet the impact method will work.
 
#9 ·
Well I've heard that you may have to grind the wrench being used down a bit to get rid of the taper on it so it fits flush....so nobody knows the size huh?
 
#11 ·
The size of the race valve? 18mm. Also all rounded bolt remove kits jump from 19mm to 17mm. They all skip that 18mm size that I could totally use!
 
#13 ·
Vise grips or a file to make two new sides so the open end of the wrench will fit on again...
 
#12 ·
Man mine glow plug controller came right out even the bracket, the plug is 18mm and I connected two wrenches together+ some MAN and It came right out. I used a scribe to get the old oring off and put some Vaseline on the new plug and old oring and it went right on. My tq wrench didn't fit in there the tq was like 66 to 72 ftlbs, PPE came with instructions, but I just connected two wrenches to get it back in. I'm an aircraft mechanic so I'm damn close when feeling when a tq is within it's range. I drive the truck hard and it runs much better, no leaks at all.
 
#15 ·
Rail plugs are a lot simpler to deal with then trying to take apart your factory valve and shim it out. Every duramax we have here at our shop has a rail plug and we are making from 600-1200hp with zero problems.

They can be a mofo for sure to swap over tho. As mentioned above, remove the GPCM and it helps to have a wobble end breaker bar because yes, the hand of god himself tightened them things in there.
 
#19 ·
The shim kit is just you adding two washers to the existing FPRV to increase the spring constant...the race valve is litterally just a plug that you are installing that won't function as a valve at all therefore not letting fuel leak by at WOT
 
#22 ·
Ive tried an 1/2 impact actually. My only problem is finding a socket to bite now because its rounded. I actually went and bought a 33 gallon craftsman air compressor with the air tools just for the FPRV haha. If I had a socket that would fit and bite, I'm sure it wouldn't be too much of a problem.
 
#23 · (Edited)
Ive tried an 1/2 impact actually. My only problem is finding a socket to bite now because its rounded. I actually went and bought a 33 gallon craftsman air compressor with the air tools just for the FPRV haha. If I had a socket that would fit and bite, I'm sure it wouldn't be too much of a problem.

There's not much room in there so the 1/2" gun may be too big and causing you to impact off angle a bit and losing some effectiveness because of it. Also are you using swivel impact sockets? Usually when you round off the FPRV manually, there's some untouched hex left in the rail to bit to when using the impact sockets since the head of the FPRV is slightly recessed into the fuel rail.
 
#24 ·
I wound up taking my whole rail out, wasn't that bad. Sucker was super tight, the impact gun took a few hits to get it moving even in the vice.
 
#25 ·
How long did it take you to get your rail out? I feel that I may unfortunately have to do this...has anybody taken a rail out before and could give me a time frame? I haven't rounded the head off quite yet, I can get my wrench on there and pull with all I've got and it won't break lose. But the problem is half my strength goes to just holding the wrench flush on the bolt and not yankin on it at an angle. I fear it will end up rounding off in the end though, I started out using a sh!t cheap wrench I bought that day from autozone and it was crap and did a little damage to the head. Went and then bought a kobalt and it holds on strong but the 6" wrench doesn't give me enough leverage and I can't seem to get a configuration for adding leverage that won't cause me to just pull the wrench off the head due to some severe angle. HELP
 
#27 ·
When I do the fprv I hit the wrench with the heal of my hand to break it loose instead of trying to muscle it. This prevents it from rounding off. I've done it this way and it makes it a simple job instead of a real PITA.
 
#33 ·
You have to pull the bracket out apparently that the control module and its black sheet metal bracket are attached to. Then a socket will.

And yea honestly the only way I can see using a breaker bar is having someone hold the socket on while somebody else pulls, otherwise I see it just popping off each time and rounding it more and more.
 
#31 ·
A shim increases the amount of pressure required to pop the FPRV and a race valve blocks the line.

In theory a shim is the "safer" way to go, but I've never heard of anybody having any issue either way.
 
#32 ·
I think the big fears came from several years back when stacking was big. CumminGs guys would use a box that added both pressure and timing, then stack a pressure box on top of that which could create dangerous rail pressures.

I like to think that Duramax guys are smarter then that. lol
 
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