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Resetting injector pop pressure

are the NA and turbo nozzles the same? i asked one guy for a quote to re set the pressure and he quoted 25 per injector (YEAH RIGHT!!!) and said he "might have to change the nozzles" sounds like a rip off to me. so many mechanics in toronto are scammers....
 
bk95td said:
Each step in thickness raises or lowers the pop pressure 50 psi. I've only used 4 different thickness shims in 12 injectors. The shims vary .05 mm in thickness. You just repeat the process untill they reach the correct popping pressure.
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Do you think a good way to go would be to pop test them all and then by seeing how far you have to raise the pop pressure, you could order a decent amount of the shim sizes you would need? Know what I mean?
 
turbovanman said:
What is too high a pressure to start making the IP wear out faster?
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Well, as everyone knows, our IP can run 11000+ psi line pressure, and it absolutely goes well over pop pressure when increasing fuel rate and RPM.

Since the IP can routinely and repeatedly reach 3-5 times the stock pop pressure would raising the pop pressure 10% really impact the reliability from the amount of idling? Good question, I would doubt it.

I have only run these "marine" injectors, but more experienced persons have told me that somewhere around 2500psi will start to make idle crappy. And 6.2Turbo says the IP's top out at about 4500psi at idle rpms.

So me personally would only set them up to 2400psi, and expect them to settle a bit lower over time. "marine" injectors are set to about 2175psi.
 
You could test each one ,write down the pop pressure its at and then take apart and measure the thickness of the shims that are in it if you want to go to the trouble. Then figure aprox. how much each injector will take. I never measured what was in them just replaced with 1.85-2 mm on the delphis. Sean will sell you however many of each thickness shims you want. I;m not shure how thin he carries. I went with single shims in the ones i've done so far other than the 1 that needed 2mm.
 
buddy said:
Well, as everyone knows, our IP can run 11000+ psi line pressure, and it absolutely goes well over pop pressure when increasing fuel rate and RPM.

Since the IP can routinely and repeatedly reach 3-5 times the stock pop pressure would raising the pop pressure 10% really impact the reliability from the amount of idling? Good question, I would doubt it.

I have only run these "marine" injectors, but more experienced persons have told me that somewhere around 2500psi will start to make idle crappy. And 6.2Turbo says the IP's top out at about 4500psi at idle rpms.

So me personally would only set them up to 2400psi, and expect them to settle a bit lower over time. "marine" injectors are set to about 2175psi.
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Good info, I had read the Marine injectors were set higher but then it would cause the IP to wear out faster.
 
So higher pop pressure has no effect on IP longevity?

If the psi pops at 2300 psi, the IP is SO fast that even though the nozzle is open, it still continues to build pressure? Yet the spray pattern stays consistent throughout the cycle, or does the spray pattern change as pressure increases?
 
Matt Bachand said:
So higher pop pressure has no effect on IP longevity?

If the psi pops at 2300 psi, the IP is SO fast that even though the nozzle is open, it still continues to build pressure? Yet the spray pattern stays consistent throughout the cycle, or does the spray pattern change as pressure increases?
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I dont think it has been proven to reduce longevity, and I dont expect it would with 10% or less increase. As long as it can maintain good idle.

The increase is not totally helpful unless you are running increased fuel rates and run it to the max fuel rates often. So accelerating like I do or racing or towing heavy a lot.

Yes the IP builds pressure even after the injector pops. Presure must go up for more volume to flow in the same amount of time out of a fixed nozzle.

Also, Heath sells "high output" injectors, which must mean larger nozzles, not just higher pop pressure. SSD also said theirs have larger nozzles. I'll pull one apart at some point and see what in there.
 
I think I'll tell the guys, at the injection shop to set mine at 2200psi,, then when they settle, I'll be around Marine spec's
 
Pruittx2 said:
I think I'll tell the guys, at the injection shop to set mine at 2200psi,, then when they settle, I'll be around Marine spec's
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Thats a good plan.

The Stanadyne shop near here sells Delphi injectors, not sure if its because they know they are better than Bosch or just because thats their source.
 
It would be interesting to tell them to set them at 2300 just to see what they say about it.
I have a feeling they would tell me that's not recommended, and they might not do it. But you never know. Hmm I wonder how much they would settle down to over time.
 
buddy said:
I dont think it has been proven to reduce longevity, and I dont expect it would with 10% or less increase. As long as it can maintain good idle.

The increase is not totally helpful unless you are running increased fuel rates and run it to the max fuel rates often. So accelerating like I do or racing or towing heavy a lot.

Yes the IP builds pressure even after the injector pops. Presure must go up for more volume to flow in the same amount of time out of a fixed nozzle.

Also, Heath sells "high output" injectors, which must mean larger nozzles, not just higher pop pressure. SSD also said theirs have larger nozzles. I'll pull one apart at some point and see what in there.
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What does the spray pattern start to do with all the added pressure?
 
Anytime pressure is increased atomization increases within a given orifice.
 
To throw a little more in the mix here, I was on a mercedes forum and they were talking about having their injectors extrude honed. It was costing them $50 per injector to have done:eek:. They were also having the pintle modified for more volume of fuel. 3 flats on them. The 6.5 turbo pintle has 1 flat spot.So there is more that can be done to the injectors for more fuel output. Figuring out how much extrude hone to do or where to put the flats is the tough part.:confused:
 
bk95td said:
You could test each one ,write down the pop pressure its at and then take apart and measure the thickness of the shims that are in it if you want to go to the trouble. Then figure aprox. how much each injector will take. I never measured what was in them just replaced with 1.85-2 mm on the delphis. Sean will sell you however many of each thickness shims you want. I;m not shure how thin he carries. I went with single shims in the ones i've done so far other than the 1 that needed 2mm.
Click to expand...

Thanks for all your help, Bk. I really appreciate it!!
 
bk95td said:
To throw a little more in the mix here, I was on a mercedes forum and they were talking about having their injectors extrude honed. It was costing them $50 per injector to have done:eek:. They were also having the pintle modified for more volume of fuel. 3 flats on them. The 6.5 turbo pintle has 1 flat spot.So there is more that can be done to the injectors for more fuel output. Figuring out how much extrude hone to do or where to put the flats is the tough part.:confused:
Click to expand...

a lot of the tdi guys do this too
 
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