DIY CP3 mod
Registered User
Joined: Dec 2006
Posts: 136
Likes: 0
From: Indianapolis Ind
I did the Mod. Now I get a surge in rail pressure and I cant get the dang screws out they stripped. Over all I like the mod. The bottom end is nuts. I only get the surge under 1/2 pedal from like 20-25k psi. If I nail it it doesnt surge. Im wondering if its the lift pump not pushing enough. So I guess once it warms up I will try to either take the cp-3 off and change the FCA and or add the walbro kit. If anyone has had this problem please chime in.
Banned
Joined: Jun 2004
Posts: 0
Likes: 1
From: kingston,wa
come rich, give it to us. i have a buddy in the machine shop who runs the edm, and i talked him into making an electrode to the shape i need, help wire it out for me so i dont have to use a dremel.
give us some words. like screw size to replace the rivets, what tooling you used. can you hold the valve lengthwise in a softjaw vice to hold it steady instead of your hand. etc.
give us some words. like screw size to replace the rivets, what tooling you used. can you hold the valve lengthwise in a softjaw vice to hold it steady instead of your hand. etc.
Registered User
Joined: Jan 2005
Posts: 381
Likes: 0
From: PA.
alright enough with the wise cracks now 
first off I ended up just modding the fca with a dremel for now,I'm going to get another fca too play around with but for now I justed wanted to see what my results would be.the only slight issue I have so far is at start up the truck fires right up but then the idle drops down for a split second like it's gonna stall but then comes right back to normal idle.when out driving it's just smooth power,I have virtually no turbo lag since doing the mods,the bottom ends is just awesome and it just pulls harder through the entire rpm range,I don't have my rail pressure guage hooked up right now so I'm not sure what the mods did for my rail press.my boost also comes up much quicker 0-32 psi in a split second.so far the mods have been worth the two hrs. and no money that it cost me
I modded the fca basically just like relentless explained,put a cut across the very bottom of the triangle,on the end cap I oblonged the hole so that it would still hold the spring but allow more fuel through,on the gear pump I drilled out the inlet and outlet ports,there is a little bit of a step in these two holes I drilled each one out to remove that step.
to hold the valve to make the cuts I used a piece of leather on each end and lightly pinched it in the vise(i' wasn't in the mood for a trip to the local hospital with a missing finger tip )when drilling out the rivets I used a 3/16 drill bit and drilled completely through the pump then used 3/16 machine bolts to put it back together.
first off I ended up just modding the fca with a dremel for now,I'm going to get another fca too play around with but for now I justed wanted to see what my results would be.the only slight issue I have so far is at start up the truck fires right up but then the idle drops down for a split second like it's gonna stall but then comes right back to normal idle.when out driving it's just smooth power,I have virtually no turbo lag since doing the mods,the bottom ends is just awesome and it just pulls harder through the entire rpm range,I don't have my rail pressure guage hooked up right now so I'm not sure what the mods did for my rail press.my boost also comes up much quicker 0-32 psi in a split second.so far the mods have been worth the two hrs. and no money that it cost me
I modded the fca basically just like relentless explained,put a cut across the very bottom of the triangle,on the end cap I oblonged the hole so that it would still hold the spring but allow more fuel through,on the gear pump I drilled out the inlet and outlet ports,there is a little bit of a step in these two holes I drilled each one out to remove that step.
to hold the valve to make the cuts I used a piece of leather on each end and lightly pinched it in the vise(i' wasn't in the mood for a trip to the local hospital with a missing finger tip
)when drilling out the rivets I used a 3/16 drill bit and drilled completely through the pump then used 3/16 machine bolts to put it back together.