Okay so installed my dual cp3's, and when at WOT my rail pressure bounces to 27-29k and then falls down to 20-22k.
Dual cp3 rail bouncing
- Thread starter Cknight199
- Start date
Sounds like tuning still needs tweaked if it's a ii pump it has a modded regulator and sometimes there almost impossible to make work perfect
Okay, only thing that I should mention is typically there are two hard fuel lines that go where the stock y bridge is. Well I installed my own y bridge and took those and replaced them with fuel hose. Now one of the lines is an injector return line that merges with the cp3 return line. Instead of trying to fit the return line with the other cp3 return line (since it's super tight under the upper radiator hose), I just tied the return line into the injector return line which ties into the cp3 return line anyways. Didn't think it would be a problem but now that Dustin mentioned it I figured it would be best if I shared.
That will be fine. Your returning fuel somewhere else. I replied to 07metallicgreens thread. But it's either your rail fitting or the block for the high pressure lines to the driver side rail. Since one pump is modded I don't see that pressure would be low, high makes more sense to me.
Can't remember if trevor put a race valve on that truck or not or did you put one on?
does it throw any codes?
does it throw any codes?
No codes, it's running with a race valve in that block as my tunes ask for 28-29k of rail for the big tunes and didn't want it being a problem.
When is the stock pump supposed to be here? I honestly wouldn't mess with it anymore till you have the stock pump on and the 85% off.
exactly. i watched an injector blow apart from a modded pump and stock pump surging.
If your running alot of fuel, looking for big power you should have injectors returning to tank seperate from pumps. But thats not your issue. From my experience with modded and stock pumps, its the mid pressures that are hard to control. Not full bore WOT pressures. Having modded and stock is not always a problem, just more often then not its not the ideal setup. Could you isolate the issue by running either pump at a single time with your jumper harness?? Maybe one pump is shot.
Meaning unplug one of the pumps? If I unplug the top pump i get a bad fuel rattle, almost like pilot injection is turned off. Not sure if that's normal or not.
you have to put the stock fpr plug back in the valley fpr, bypass the second pump with a stock belt and you should be good. unplugging the reg makes it go wide open to max pressure
I'm just answering what you asked above. That's how you bypass the second cp3. Just pulling the plug won't do a thing for ya
Thanks for clarifying and the info, looks like I will end up either finding another pump or getting a retune for the 85% over pump.
Sounds like the tuning needs a bit of re tweaking. If you put a quality stroker over a stock one (fleece, exergy, wicked,etc) then tuning can be done fairly easily but like everyone said, yank that II pump over and that will more than likely fix the problem.
Id be cautious of running the truck much with it bouncing, I've seen cranks break that way.
Id be cautious of running the truck much with it bouncing, I've seen cranks break that way.
Thanks, I'm not entirely sure if it's an industrial pump or not.
Edit: it's an industrial pump.
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