Finally got it all together. Dry pavement let me test my truck tonight for about 1 hour. I loaded the 'extreme' Diablo Predator tune and ran it for about 20 minutes by itself. EGT stayed in the 1100/s on the end of 1/8th runs. Happy with egt there...but my rail wouldnt go above 20,000 ??? Curious about that. It hit 25,000 a couple nights ago.

Boost was in the 58-60 pound range with the converter locked in.

After the runs the rail would go to 5500 and stay there while idiling.
I then ran extreme Predator with level 3 on the Edge next.
Same stuff but egt hit 1350 and 1400 twice.
Weird observation - Rail still 20,000???
Engine water temp got up to 215 after the last 1/8th.
MPH was around 89-90
Weird?? One run the fuel pressure zeroed for a split second and then came back to 17psi
Boost may have been a tad higher.

Let it idle everything was fine.

50 minutes in I decided to go with both Predator and Edge on Extreme.
I finally got to drive a vehicle that I can honestly say scared me.
Ive heard people say this, but I never experienced it - I kicked the OD off and layed the fuel down and the rear tires would break lose at 60 MPH. Very weird feeling to have the tail end of a 8000 LB vehicle come out from underneath you going 60 mile per hour.

I saw a major jump in boost. I really feel I saw higher than 65 pounds, but i cant know for sure cause I was a little concerned about the road and the feeling of not being in control...

Weird? - One run the fuel pressure zeroed again for a split second and then back to 17 quickly.
Weird ? -Next run the rail guage still only 21,000????
EGT was hot, hot, hot 1650ish after I went WOT.
Engine water temp 223. Cooled back to 190 quick.

Guys,why is that rail pressure screwy? Is there a major problem with my guage maybe? Anyone come up with a better rail guage for duals yet?

P pump pullers here I come

 

1650* , you drained the rail. how are you reading rail pressure? on a digital gauge? i went to dual cp3's and had to add another lift pump as 1 wasnt enough and i was draining the rail do to lack of fuel supply to the cp3's. your rail pressure seems low but if your using a digital gauge,,, well i dont trust them after using a di-procal anolog rail gauge vs my 2 other digital ones. they dont keep up with the rapid changes in pressure.

 

I got the di-procal - a little over a year old. There was some disscussion of that rail gauge being updated. Do you have a newer version of their rail gauge?

Air Dog 150 with 1/2 inch lines isnt enough?? Oh my goodness

 

Your rail gauge could be out some, I have been through two dip. gauges, I'm not aware of the newer version.
In comparison, if I run no pressure with a heavy fueling tune my rail is 21-25k. It will start lower until the rpms come up. With pressure it hit 28k, not so good. Trying to find the perfect spot is not always that easy, heck 21k seems pretty good.

With respect to the feed pumps, they have little chance to maintain 18psi when the demand is so big down low. The pumps would have a lot better chance of maintaining a solid 20psi if you could set the pressure higher to begin with. All the dual pump kits like lower feed pressure, and until that changes, feed pumps will struggle to maintain low pressure numbers at super high demands.

I would say A/D 150 is lots. Are there numbers or facts to prove that you are loosing power with 5,10,15 psi feed pressure. I have not seen it. The important thing is good volume lower pressure and steady rail pressure.

o.

 

Oneton is Exactly right

my fuel pressure with PPE dual cp3's stays around 13-15 lbs consistent fuel pressure with a fass 150 system , this has proven to be more then enough fuel pressure for the dual cp3s & at the same time the combo still holds excellent rail pressure

 

If you are concerned about FP...Glacier Diesel Power sells a spring that will jack the AD150 from 15psi to 30psi.....think it was $9.

 

The Dipricol RP gauges are also digitally controlled. There's no such thing as a true "analog" RP gauge.

 

i realize that.
what i mean is its too hard to read it alot of the times, just cruising down the road steady throttle input,,, yeah pretty easy to read as it only changes a couple hundred psi. but under full throttle shifts or short runs, 9???,112??,148??,18???,21???. its harder to read in digital form (for me) compared to the "analog". my rail guage will start to "gain" if i put much rail pressure to it.

 

All they do is read the return voltage from the RP sensor and convert that to something you can read. If you have access to a good volt meter and can make a break-out harness (or use the correct back probe) you could record the voltages on a 1/4 run. The center pin on the rail pressure sensor is the sensor return and thats the one you want to monitor.

 

If anything the digitals read faster than an analog display. A lot of people don't like the digital readouts for the same reason you mentioned though...too hard to read with constant fluctuations. The really nice thing about a digital readout is that you get a peak recall feature so you don't have to stare at the gauge trying to see the maximum.

Aren't the Dipricol RP gauges the ones that people usually have problems with when running twin pumps?

 

Al, go put your injectors in. Get off the internet! LOL

 

LMAO, Thanks for getting turned around and back.


THANK YOU