Stroker vs dual cp3 question

OleBlackyLBZ

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May 22, 2020
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Okay, I know there are tons of discussions about this topic already. But I have been reading old cummins forums from back like 2015ish where guys were saying that stroker cp3's were laggier than a stock pump/dual cp3 set-up, is that even a thing? Or if so, has better tuning just eliminated it as an issue? I'm a huge fan of singles myself and before reading this saw no advantages to duals. Simple and easier install, less clutter, stock belt, no belt popping off issues, no extra heat added to the fuel, probably more I'm forgetting... But if it was a street truck only and really is snappier with dual stockers I feel that would actually be something to consider...
 

08lmm72mm

Active member
May 13, 2019
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Saskatchewan, Canada
My 12mm fuels instantly watching FRP on my CTS. Picked up all kinds of power on the low end vs stock cp3. Between the belt and controller issues it was an easy choice for me. Go stroker IMO
 

Chevy1925

don't know sh!t about IFS
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Oct 21, 2009
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if its lazy, its a tuning/FPR control issue (assuming healthy fuel system and good cp3). there is 3 tables in EFI Live that are DPI or PID or something like that. this controls how quickly the fpr should be changing and adjusting to fuel pressure to match desired. it can cause overshooting of pressure and yo yo up and down if not done right but it can really make different cp3's work well. even on dual cp3's
 

2004LB7

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Dec 15, 2010
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if its lazy, its a tuning/FPR control issue (assuming healthy fuel system and good cp3). there is 3 tables in EFI Live that are DPI or PID or something like that. this controls how quickly the fpr should be changing and adjusting to fuel pressure to match desired. it can cause overshooting of pressure and yo yo up and down if not done right but it can really make different cp3's work well. even on dual cp3's
yep. they are PID tables. I'm not sure when the change happened without going back and looking but some of the newer then LB7 have 6 PID tables. three (low, med, high) for amount of change and another three for a time quickness of response.

they can be tricky to adjust as it's very easy to create a surging fuel pressure that the ECM has difficulty controlling.

they are essentially the tables the ECM uses in it's algorithm to deviate from the mA to pressure table in order to maintain desired pressure
 
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Chevy1925

don't know sh!t about IFS
Staff member
Oct 21, 2009
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yep. they are PID tables. I'm not sure when the change happened without going back and looking but some of the newer then LB7 have 6 PID tables. three (low, med, high) for amount of change and another three for a time quickness of response.

they can be tricky to adjust as it's very easy to create a surging fuel pressure that the ECM has difficulty controlling.

they are essentially the tables the ECM uses in it's algorithm to deviate from the mA to pressure table in order to maintain desired pressure
thats it!

small changes are key, took me a while of tweaking/driving to get it dialed.
 
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juddski88

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Jul 1, 2008
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The best way to dive into PID tuning is to research quite a bit of PID control theory and technique. You'll likely conclude, as I did about 10 years ago, that you only should be making slight changes to the Proportional values to get what you need out of the FPR. I did because I was running a stock lbz pump in the valley and an underdriven prototype cummins-based Industrial double dragon pump as my second pump, with lly injectors, off lb7 electronics....never again...
 

Bdsankey

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Feb 1, 2018
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IMO they both have their benefits. Dual stock pumps are cheaper overall, offer the same fuel as a 12mm (approximately), and are easily replaced should one fail on the road.

Personally, I prefer single stroker pumps as they don't add extra wiring, plumbing, or clutter to the belt plane. The days where stroker pumps are "unreliable" is behind us IMO. I had well over 50k miles on my old 10mm and had zero issues.
 

2004LB7

Well-known member
Dec 15, 2010
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The best way to dive into PID tuning is to research quite a bit of PID control theory and technique. You'll likely conclude, as I did about 10 years ago, that you only should be making slight changes to the Proportional values to get what you need out of the FPR. I did because I was running a stock lbz pump in the valley and an underdriven prototype cummins-based Industrial double dragon pump as my second pump, with lly injectors, off lb7 electronics....never again...

don't forget the logs too. invaluable for determining where you need to make the changes too.

on my modded CP3 it took maybe a dozen revisions to get the idle smooth and at the desired pressure. when I tried out duel CP3s I don't remember having to make any changes and it ramped up quick.
 
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