Dr. Performance question

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BACummins

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Jul 6, 2012
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Hey fellas I've got a question about my Dr. Performance pressure box. I know that the company is no longer in business and I did see the dip sh!t owners thread pretty much sending out a big F you to the diesel world. My question pertaining to the box is about the tune it has. The guy I got the box from said he sent it back to Dr. Performance a couple of years ago for a bigger tune. The tune is supposedly called the "pump killer" or "pk" tune. I was just wondering if anyone has any information on this tune or any experience with it? It runs awesome with the smarty. I very rarely turn it on though. Any input is appreciated.

P.S. The tune is pressure only with no added timing.
 
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Yeah it seems to run ok. I know the name of it sure sounds stupid haha. I would just like to find a little info on it.
 
If you are talking about your 2000 Cummins then it's not a pressure box, no such thing on the VP44 since it's your traditional jerk-pump injection system. Power is made by duration on the VP44, and most boxes add timing including the Dr P.
 
VMacKenzie said:
If you are talking about your 2000 Cummins then it's not a pressure box, no such thing on the VP44 since it's your traditional jerk-pump injection system. Power is made by duration on the VP44, and most boxes add timing including the Dr P.
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Well I guess I learn something everyday haha. So correct me if I'm wrong, but duration is just how long the injection event is, correct? Your post makes sense if so. I really don't think the box adds any timing though. I run it with my smarty on 9 with no ill effects or timing rattle. Although I don't run it constantly, I just flip it on when I feel like screwin around. Nothing more than about a 10-15 second pull through the gears.
 
I thought it was a pressure box also! I know years ago tst told me they tried upping the pressure on the pumps (they have 2 or 3 stages in the vp44) of pumps. If I'm thinking correct, but mark told me they played with the pressures some, and didn't see a gain in performance.

I don't know anything about the dr performance box though, does it plug up to the map and can-bus?
 
Plugs into the MAP and taps the pump are the only places goes. It gets its power from the battery and there is an on-off switch that goes into the cab.
 
BACummins, yes duration is how long the injection event lasts. Timing that is discussed is when the injection event starts. As you roll into the throttle the injection event goes longer and longer, the piston is further down when the injector shuts off. But as RPM rises the injection even starts earlier and earlier (timing advances), on a VP44 it ranges from about 8* before top dead center at idle to about 25* BTDC at redline as I recall.

The only way I know of to raise pressure on a VP is to increase the pop pressure on the injectors. I think the VP44 operates up to about 14000 PSI, it does vary some with RPM and fueling amount but it's not a controlled parameter like it is on the common rail engines. The principle of operation is very different between the two.
 
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I was curious on how tst bumped the pressure up on the pump so i called mark and he said he did it mechanicly! So the box is like VMacKenzie was saying just timing. But i dont think the vp44 will go from 8* -25* with out a box, maybe 8*-16*, and most of the guys that have a fms say they run as high as 18,500psi if i understood them right.
 
I dont know what i was thinking on the last post, i read ur post again where u said the boxes hooked to the map and the pump wire! If that is the only 2 places it hooks to than it a fueling box!
 
Thanks for the help guys. I was pretty sure it didn't add any timing but I've been wrong before. I am just trying to get a little information on the box. Kinda bugs me not knowing exactly what it is.
 
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