Any feedback on cncfab stage2 hpop?
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ja_cain
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You might be right. Do you have data/references on this? I'm still trying to wrap my brain aroind the higher VOP. I can see the benifit in initial start of injection, but I don't see any benefit after that.
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All I have found is multiple threads from the past when a good deal of the injector builders use to post more frequently on these subjects. I have found and recalled Charles saying he experimented with different VOP to find the same. Cleaner burn, louder idle and overall more noise, but loss of power on the dyno. Not sure if he ever tweaked tuning to compensate for the VOP increase. He said he ran some Hybrids with B code springs. Unlimited once stated wat back in 2008 from an old thread I dug up from PSN
... "The springs never seemed to make a difference. We have ran as low as 2675 and as high as 4500 VOP and as charles has stated, it seems to run better at the lower VOP. Also, the higher the VOP the later the injector opens, and the shorter Injector Pulse Width (read: ACTUAL TIME, NOT REQUESTED TIME that the injector is delivering fuel). I believe that 2675 is enough no matter what size holes you are running"
Now wether it has an huge effect I am unsure. I can see how it can help to clear things up in lower rpm low ICP conditions like towing and idle etc etc. Overall performance the lower VOP would likely stand firm. Some have been able to tune even 400% nozzles to be street daily driven friendly but its quite the challenge. It would be interesting to take a 400/400 injector either B code or hybrid does not matter and play with VOP and see if a 400/400 would be cleaner with a higher VOP of course however likely sacrificing some high end power.
... "The springs never seemed to make a difference. We have ran as low as 2675 and as high as 4500 VOP and as charles has stated, it seems to run better at the lower VOP. Also, the higher the VOP the later the injector opens, and the shorter Injector Pulse Width (read: ACTUAL TIME, NOT REQUESTED TIME that the injector is delivering fuel). I believe that 2675 is enough no matter what size holes you are running"
Now wether it has an huge effect I am unsure. I can see how it can help to clear things up in lower rpm low ICP conditions like towing and idle etc etc. Overall performance the lower VOP would likely stand firm. Some have been able to tune even 400% nozzles to be street daily driven friendly but its quite the challenge. It would be interesting to take a 400/400 injector either B code or hybrid does not matter and play with VOP and see if a 400/400 would be cleaner with a higher VOP of course however likely sacrificing some high end power.
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ja_cain
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I have skimmed few patents over the past couple of days and it seems higher VOP is desired at higher RPMs and loads. I almost feel like having the opening and closing of the injector mimic a step function is more desirable under these conditions then at idle where you want to ease things in and stretch out the event to facilitate smoothness and less noise. Looks like Caterpillar or someone associated with their technology went so far as to file a patent for a variable VOP technology. Kind of interesting. They definitely saw the need/advantage. Will try to do some more in depth reading and post some links when I have a chance.
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ja_cain
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I am going to do my best to find some pressure signal traces of a 7.3 from injection, combustion to exhaust. May have to call up the guys at Swamps and see if they will share that info with me. Lol! Dave is a pretty stand up guy, and has been helpfull in the past with my dumb questions. 
m j
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gnxtc2
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lincolnlocker
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ja_cain
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Awesome! Thanks for the info. Do you have a source, or did you measure them yourself?
ja_cain
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I have been known to miss the most obvious of details too. Lol!
I found those results on some older thread somewhere long ago. Regarding discussions from the past on injectors on the older forums. It also talked about 6.0 and 6.4 hole sizes.
Update: I went looking and found the original thread the information on hole size was posted by Golfer on an old PSN thread. So I am sure its safe to say Swamps knows why they are talking about.
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ja_cain
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I have a bunch of drill bits and broaches in that range. I guess I could always grab an injector from somewhere and check it out myself.
I agree, no doubt that Dave knows this stuff backwards and forwards.
Beyond the hole size there are also different manufacturing processes to create these larger holes including EDM and EH which also have an effect on atomization. EDM has a rougher finish and EH a smoother finish. Some sizes are EDM with light EH to clean them up. A good majority of the builders I do believe are getting the nozzles from the same company these days. The multiple sources to buy the nozzles as parts are all the same Redat nozzles. Same nozzles I am running. DDP extrude hones their own nozzles which are rediculously expensive and there are likey a few other special shops who supply some builders which they will likely not tell as it's proprietary information they likey want to keep quiet.
This was also posted a year back or so when we were talking about EDM vs EH. Stock, 30, 80, 200, and 400 are edm nozzles. 100 and 300 are eh.
This was also posted a year back or so when we were talking about EDM vs EH. Stock, 30, 80, 200, and 400 are edm nozzles. 100 and 300 are eh.
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pipedobber
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I just installed the oil line kit and fuel line kit from cnc. Everything worked perfect and is nice quality, IMO. Corey very patient and helpful as well. Would definitely do business with him again.
