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OK, bear with me - crazy ideas ahead!

I was thinking 8 solenoids, the ones that are for the electronic valves (cant remember ame right now). But they operate valves on engines to 8,000 rpms. That would be great for our engine btw! Imagine vvt and all the drag lost!

And ya know- my old pump guy built my pumps and drilled my injectors. I have ran the store bought marine injectors and never opened or examined them. Just ASSuMEd they were the same. I’ve been corrected on that before, and forgot. Defaulting to what I dealt with back in covered wagon days. Yuppers you are on the right track opening them up if you haven’t yet. It works.

Sooo, higher lift marines WITH larger ports..... hmmm.
 
@Rockabillyrat,

Thank you for the Stanadyne pump details. I've never taken on rebuilding one myself, so my knowledge of parts interchangeablity is a little weak.

Seems you have some rather wild experiments planned! I'll be waiting for updates, as it sounds rather amazing.

Also the cam lobe lift rates between DS & DB is also a little shocking! Looks like that DS ring flattened it self, by visual comparison.
 
I could be mistaken but I thought I've read in the past that gm ecm/pcm capped the max "tunable" FS duty cycle in the code. I also seem to remember tuners explaining that, that part of the code is not the typical variety which they would alter.
It's more a limitation of the physics of a rotary injection pump. You mechanically need to move more fuel volume within said window of rotation, then tune back the pulse width.

A 5521 pump has a puny little cam ring to make it quiet(er) and therefore has to run a long pulse width to move fuel. Since it more or less had a fuel limiter tuned into it on stock tunes...it has room to expand, but does have a clear limit.
 
I'm not sure I had posted this before but a Bosch p7100 inline 8cylinder pump on a 6.5td would be awesome.............
 
The only downfall to a p pump is it has no way to advance timing. That's why a p pump 12v has such a small power band. It would be good for competition use. I just wonder how it would be for street use. But I would love to see a p pump p400!!!
 
The only downfall to a p pump is it has no way to advance timing. That's why a p pump 12v has such a small power band. It would be good for competition use. I just wonder how it would be for street use. But I would love to see a p pump p400!!!
I am confused by this statement as the P pump can be manually advanced and governors can be tweaked for higher rpms so what am I missing here?
 
I am confused by this statement as the P pump can be manually advanced and governors can be tweaked for higher rpms so what am I missing here?

A P pump doesn't advance timing as the RPMs increase like a rotary pump does. I think only the bigger cummins p pump did. But I though the 8 cylinder pumps have no advance.
 
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@quadstar87,

Interesting on the mech limitations vs the code. If you have the time, I'd love to pick your brain on the numerous reports of extraordinary pwr during pmd runaway!

Do you think is all psychosomatic due to driver stress during the event, or real seatdyno experiences. If the latter, is it due to extra fuel, purely because of uncontrolled injection advanced, all the above?

It just seems to me that too many 6.5 experienced drivers/wrenchers have made that statement about the pwr. Also seems it could be a readily reproducible on demand effect, with some additional electronics.

@FellowTraveler
Yes I've eyeballed P7100 8cyl pumps before. Actually really kicking myself in the rear for passing up batches of nos units being auctioned off at governmentliquidation.c*m years ago. It seemed like they sold pretty cheap too - hindsight, its too painful! On a side note, somebody at their parent Co must of pissed of someone at the Gov! Because it seems like their not on the GSA perfered list anymore - no more auction items!

Anyway, what about the larger DS-like offerings from stanadyne? Thought I've read they have a "JS, or was it JD" line of rotory pumps that have a FS and advance stepper motor like the DS? Somthing about large farm tractors using them. If easily adapted to fit the 6.5, perhaps that may be any easier path to more fuel? As the inline pump are physically (in my best Trump voice - Huooooooge).
 
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