While I'm Making CP3 Controllers..
- Thread starter Fingers
- Start date
o man, you don't even know... He made my dual cp3 controller last week the day before we left for the DPC, based on Finger's diagram. Of course he would have all the parts at his house, and of course it worked flawlessly. But man, get him thinking about triple CP3 controllers and out comes the flux capacitors and space shuttle computers...
There is no need for all the extra data. You only need to dampen the slave pump's response to the control signal. PID loops work well for this in micro-computer controlled systems, but you can do something similar with an analog circuit.
Great info guys! I wonder if just a wide open switch would suffice for the 3rd cp3? This is a dedicated sled puller so drivability is not a concern.
the issue i would see with no pwm modulation would be faster wear on cp3 parts....but im no expert
Just what I've seen with the Rail Pressure boxes on Cummins...such as the DR performance Box. it spikes pressure so fast that it hammers on the pump and the pumps fail a lot faster...at least the ones I've seen and installed. these pumps are not bulletproof, they are susceptible to high heat damage and easily endangered of failing due to low lubricity of fuel, and pressure spikes and higher flow demands just increase those dangers
we made 2 of them, we put one of the prototypes on a daily driven truck with triple pumps and it idled just as smooth as stock. we are just finishing up making a weather proof box around the controllers so we can do some road testing and i should be going back to the dyno with my engine in the next couple weeks so we can chase any bugs out that we might have. all of the bench testing with the oscilliscope looks good so far.
we heard through the grapevine that having a 3rd pump come on full bore instantly it causes alot of problems with the computer trying to adjust the other two pumps to even out desired and actual fp.
basically you're just tripling the computer signal output and current to control 3 regulators. at idle the regulators are seeing the most current because the current closes the regulator, the less current the more fuel is allowed to go to the rail, thats why when u unplug a regulator u get 26k rail. the computer doesnt know that there is triple the volume going out it just sees the actual fuel rail pressure from the rail sensor and adjusts the fuel going by the regulator by moving the amount of current going to the regulator up or down. it just trys to keep the actual rail pressure and desired rail pressure in check with each other.
the box we built will control up to 4 cp3's if everything works out.
correct... from what i was told if the regulator is not doing its pwm thing it will stick at one spot
Send me a PM also Jon.
I should have my truck done by the end of this month. I have a dyno time setup with Danville on June 6th. Were going to see how your pistons hold up. After the dyno were going to the track to make some shake down runs.
I should have my truck done by the end of this month. I have a dyno time setup with Danville on June 6th. Were going to see how your pistons hold up. After the dyno were going to the track to make some shake down runs.
PMs Sent to those that asked.
Pressure control is easy at idle. It is at the higher RPMs that a lot of the twin kits have issues. Seen many a plot of the pressure jumping all over the place. The result is a huge variation of the pulse width as the ECM tries to control the pressure and match the fuel delivery to the indicated pressure.
Pressure control is easy at idle. It is at the higher RPMs that a lot of the twin kits have issues. Seen many a plot of the pressure jumping all over the place. The result is a huge variation of the pulse width as the ECM tries to control the pressure and match the fuel delivery to the indicated pressure.
GMC_2002_Dmax
The Still Master
EFI-Live has given us the control in the tune files to adjust the reaction to low or high fuel pressure, you can adjust the effect on fuel pressure with those tables.
BTW, nice work, all we need now is a good source of fuel lines and fittings without getting robbed.
:thumb:
BTW, nice work, all we need now is a good source of fuel lines and fittings without getting robbed.
:thumb:
I can revisit the Parker flex line idea for group buy, since thats what I ended up using, but exergy lines are custom and fair priced in my opinion Tony.
I was wondering if "Parker" had braided or heavy line that could hold the pressure.
Gentlemen, just a little while ago, Jeff was asking this very question:
http://www.duramaxdiesels.com/forum/showthread.php?t=37776&highlight=braided+line
Rob Hall is running a hose from II.