Attention: TDR Forum Junkies 
Blasphemy You Say !?
Anyways, not really de-bombed just less bombed. Here's the story:
Decided I'm blowing too much fuel out the tailpipe when the engine is cold which is not a good thing since it's winter and getting colder -- and, more importantly, I plow snow. One thing I don't need pushing snow is a smoke cloud to rival the blowing snow. Now, keep in mind I don't mind a little smoke while working through the gears but the constant stop and go while plowing is another matter entirely.
So: decided to 'downgrade' to RV 275 injectors (straight from Bosch).
275's from DDIII's:
Put those babies (275s) in two weekends ago -- I really like the drivability. This thing purrs like a kitten. Very smooth take offs. Definitely less umph when I get on it (of-course) but there is literally ZERO smoke -- even with my original PowerMax engaged and a full throttle take off. See conclusion below for performance impact overall.
Lift Pump:
I noticed that my lift pump was making a bit of a racket so I replaced it this weekend ($129 from Cummins, labor myself, easy to do just hard to reach); and also removed my Prime-Loc (totally unimpressed with it). BTW: since inception this is the FIFTH generation of lift pump part number (now it's called a transfer pump). So I think upgrading makes sense if you have any doubts about your pump and you're still on the original (98. 5/99 owners).
PrimeLoc:
The bracket should not be totally supported on the intake manifold, that puts undue stress on the manifold bolts (all three of them holding it at a torque producing angle) and the gasket. When I tried to remove it I was WAY glad I was taking it off. I couldn't get the filter off! I wanted to take the filter off to make it easier to work with, but there was such a tangle of cables and wires wrapped around it where it was hanging I couldn't get a strap wrench or a standard filter wrench around it. Finally just took the whole works out in one piece. I also think the PrimeLoc is a bad idea in cold weather. Better to have the fuel filter where it's warm and near the block -- not to mention those extra lines the pump has to push cold fuel through.
ISB Paper Fuel Filter:
When I put this back in I realized why I put the PrimeLoc in in the first place. Man, getting this thing re-primed is a major pain in the butt! After mucho cranking, about a quart of diesel on my garage floor from priming, bleeding, priming, bleeding, ... . I suddenly realized why it's so darned difficult. Perhaps that paper filter needs a good soak before it will let enough fuel through? Makes sense.
DDIII:
Good injectors, I really liked them. So hope no-one gets the wrong impression.
Conclusion:
To get optimal performance plus economy balance from the DDIII's you really need more air (as hymns go up from Patton, Donnelly, and Chapple). Whether that can be accomplished with a bigger housing or if it also means an HX40 I don't know.
So how is the performance affected? Not as much neck snapping acceleration: but here's the surprise -- only sacrificed 2 lbs of boost under WOT at highway speeds! My max boost was about 38, now it's at 36! Seems to support the more air conclusion eh? To get that fuel to burn from the DDIII input it needs more air. And perhaps more importantly: I can't get this thing hot. EGT's are WAY down.
Mileage: up more than 2 mpg! The DDIIIs lowered the mileage about 1 mpg (no big deal for me, expected that, probably something to do with my lead foot). So I gained that back plus 1 more mpg, to 17 mixed city/hwy.
So: with stock turbo the 275s plus box are a fantastic combo. Great mileage, smooth running, cool temps. I was tempted to go with an HX40, but for my PERSONAL PREFERENCES (keep my Jacobs E-Brake, etc) this is a great combo. Good performance and still able to run as a work truck.
------------------
Big MAK
98. 5 ISB 5spd 4x4 Quad Cab 3500, 275s and Orignal PowerMax
A "WARRANTY FREE" ZONE
https://www.turbodieseltrucks.com
[This message has been edited by Mark Kitchell (edited 11-20-2000). ]
Anyways, not really de-bombed just less bombed. Here's the story:
Decided I'm blowing too much fuel out the tailpipe when the engine is cold which is not a good thing since it's winter and getting colder -- and, more importantly, I plow snow. One thing I don't need pushing snow is a smoke cloud to rival the blowing snow. Now, keep in mind I don't mind a little smoke while working through the gears but the constant stop and go while plowing is another matter entirely.
So: decided to 'downgrade' to RV 275 injectors (straight from Bosch).
275's from DDIII's:
Put those babies (275s) in two weekends ago -- I really like the drivability. This thing purrs like a kitten. Very smooth take offs. Definitely less umph when I get on it (of-course) but there is literally ZERO smoke -- even with my original PowerMax engaged and a full throttle take off. See conclusion below for performance impact overall.
Lift Pump:
I noticed that my lift pump was making a bit of a racket so I replaced it this weekend ($129 from Cummins, labor myself, easy to do just hard to reach); and also removed my Prime-Loc (totally unimpressed with it). BTW: since inception this is the FIFTH generation of lift pump part number (now it's called a transfer pump). So I think upgrading makes sense if you have any doubts about your pump and you're still on the original (98. 5/99 owners).
PrimeLoc:
The bracket should not be totally supported on the intake manifold, that puts undue stress on the manifold bolts (all three of them holding it at a torque producing angle) and the gasket. When I tried to remove it I was WAY glad I was taking it off. I couldn't get the filter off! I wanted to take the filter off to make it easier to work with, but there was such a tangle of cables and wires wrapped around it where it was hanging I couldn't get a strap wrench or a standard filter wrench around it. Finally just took the whole works out in one piece. I also think the PrimeLoc is a bad idea in cold weather. Better to have the fuel filter where it's warm and near the block -- not to mention those extra lines the pump has to push cold fuel through.
ISB Paper Fuel Filter:
When I put this back in I realized why I put the PrimeLoc in in the first place. Man, getting this thing re-primed is a major pain in the butt! After mucho cranking, about a quart of diesel on my garage floor from priming, bleeding, priming, bleeding, ... . I suddenly realized why it's so darned difficult. Perhaps that paper filter needs a good soak before it will let enough fuel through? Makes sense.
DDIII:
Good injectors, I really liked them. So hope no-one gets the wrong impression.
Conclusion:
To get optimal performance plus economy balance from the DDIII's you really need more air (as hymns go up from Patton, Donnelly, and Chapple). Whether that can be accomplished with a bigger housing or if it also means an HX40 I don't know.
So how is the performance affected? Not as much neck snapping acceleration: but here's the surprise -- only sacrificed 2 lbs of boost under WOT at highway speeds! My max boost was about 38, now it's at 36! Seems to support the more air conclusion eh? To get that fuel to burn from the DDIII input it needs more air. And perhaps more importantly: I can't get this thing hot. EGT's are WAY down.
Mileage: up more than 2 mpg! The DDIIIs lowered the mileage about 1 mpg (no big deal for me, expected that, probably something to do with my lead foot). So I gained that back plus 1 more mpg, to 17 mixed city/hwy.
So: with stock turbo the 275s plus box are a fantastic combo. Great mileage, smooth running, cool temps. I was tempted to go with an HX40, but for my PERSONAL PREFERENCES (keep my Jacobs E-Brake, etc) this is a great combo. Good performance and still able to run as a work truck.
------------------
Big MAK
98. 5 ISB 5spd 4x4 Quad Cab 3500, 275s and Orignal PowerMax
A "WARRANTY FREE" ZONE
https://www.turbodieseltrucks.com
[This message has been edited by Mark Kitchell (edited 11-20-2000). ]
