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Discussion Starter · #1 ·
Ok, first a little backstory. My swap was completed in 2013 and between then an 2019 I put 100k miles on the engine. Late that year a slight knocking noise could be detected and it turned much louder and there was definitely a problem. Pulled the engine and did a complete teardown and found a trashed wrist pin bearing in #4. Luckily that was the extent of the damage.

For the rebuild I had somewhat decided to build it back to factory specs. The engine is a CPL 1260 ESN# 44885446. Quickserve called for a 3802249 piston kit (0.50 over) with bare piston 3919044 I ordered a full kit which included PAI pistons. My bores are 0.50 over so the PAI part # is 111313. These are the small bowl pistons. I noticed the difference before they were installed and double cross checked the numbers that they were correct. During the teardown I noticed two of the wrist pins had an internal step on the ID and weighed different than the other two. The engine was a zero hour rebuild when I bought it and I did not make any assumption that the parts in it were correct for the CPL or ESN.

Knowing what I have delved into lately, I kinda wish I had asked a few more questions as it seems like the big bowl are possibly more desirable when i comes to performance and injector flexibility. But alas, they are in and they aren't coming out anytime soon.

So the original injectors worked perfectly fine for the early history of my ownership. I had them tested at the initial build stage. I ran pretty much smoke free but later on they had just a slight haze at full power. I figured this was as good a time as any to put a fresh set of injectors in with the fresh shiny new parts. Again back to quickserve and it called for injector 3802246. So everywhere I looked this had a cross to 3918965. I ended up ordering a set of 6 3918965 injectors off of ebay figuring I would have 4 and 2 for service spares if I needed them. When I went to install these, these injectors had the small nut bodies so my lines didn't fit. I ended up spending another $100 to have my local shop swap the nozzles on the old bodies and reset the pop pressure on them.

So fast forward to current time. I got things back on the road in February and have put about 4k miles on it already. I am not happy with the injectors. They haze at idle, haze under part load and haze at full load. Ive tried more timing and less timing and neither changed anything I am running 2.0mm lift on my VE pump as a base and ran that for many miles. I retarded the timing at least 1/4" so that should be well late enough to spray in the bowl. So I started doing some research. According to what I have found:

The 3918965 should be supplied with a bosch 0 433 175 033 nozzle (cummins 3919093) which is a DSLA 145 P 265. This should be a 6x.0098 (6x.009) (7mm tip). These tips are unmarked chinese specials. On further examination these nozzles only have 5 holes! So now I really wondered what I had. I went to the local guitar shop and picked up some string sets that had .008, .009, .010 and .011 strings. I probed to see what fit and a .010 goes on these nozzles. As best as I can tell these are 5x.010 and 145 deg tips (I measured as best as I could and the trig came out close enough that I feel good about it)

Here is a pic of the new nozzle on the left and my old one on the right.



Now my old nozzle is a genuine Bosch DSLA 155 P 170. I crossed this through some chinese source website to a 5x.012 155 deg. My 0.011 guitar string goes and I didn't have a 0.012 string to test but I believe it to be the 0.012. So i basically ran 5x.012 with no smoke in a non intercooled engine and was very happy with them. The problem is now, because of my piston choice, I can no longer run them because they are 155 deg and I need to run 145.

So now on to the multiple part question. It seems like the new nozzles are suitable for my pistons and are the size I would likely choose. But they suck. They are smokier and run a bit hotter than what I had before the rebuild

1. I am running the 7mm x 9mm adapter sleeve to install these injectors but the thickness of the "washer" part seemed thick. As in I think the injector is high in the head. Do they make selective thickness adapters like they do for the copper washers? PN and source?

2. I can't find a 145 deg nozzle in 9mm configuration in any cross references. Does anyone know if these exist and if so nozzle part #s in a 5x0.010 (145)(9mm) and a 5x0.012 (145)(9mm)

3. If I can't find some 9mm options I will go with Bosch genuine 7mm. It seems like everyone will sell you injectors for $100 each, but I kinda just need the nozzles. I have not been able to find a good cross ref for 5x.010 or 5x.012 145 deg nozzles. I did find a few on chinese knockoff sites but am going to stay away from these. Anyone have a good xref on nozzle PN.

4) Should I go with the 6x.009?

5) Any other suggestions as to a path to try or to diagnose why I am hazy with these tips?

TLDR my 5x0.010 chinese unmarked nozzles suck and haze and looking for options
 

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This is sounding very complicated. First off, the OEM injector part on Quick Serve is 3802246. Part 3918965 is not a sellable item and Cummins does not show it except as a reference. You mention the threaded tips are too small. VE injectors normally have 12mm threads. In mid 1991 smog control started to be an issue. The 91.5-93 Dodges got 7mm tip injectors which 145 deg spray angle and 6 holes and narrow bowl pistons. Your engine was made in 1993 so it has those weird specs except for the nut size. Narrow bowl pistons, 145 deg injectors with 7mm tips but has 14mm nut size, and 245 bar pop pressure. The early VE pump injectors were 9mm tips but I can't tell about your head. That CPL is really strange. It appears that your engine uses the P pump size injectors with VE pop pressure. I checked the fuel line part numbers and none are the same as the early VE pump. This thing is just an odd duck. Those 6 hole injectors were never popular for any kind of performance upgrade They didn't flow any better than the old 4x.012 they replaced. The common change was for a 5x.012 tip. But, you have to adjust the pop pressure to 245 bar instead of 260 bar. That injector is good to over 300 HP. Or, you could install 5x.012 tips on your old bodies. I had another CPL 1260 on my engine list but had never really dug into it on the injector side. Another weird thing is the early VE engine cylinder heads changed to 7mm injectors but your engine's head is discontinued with no replacement.
 

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Discussion Starter · #3 ·
Thanks for chiming in Char. I was hoping you would as you have a deep knowledge on all these cross references. For what its worth I have a 9mm head. Not sure if its the original that belongs with the engine or not. I have broken #4 fuel line in the past and used quickserve to get another one and it seemed to call out the right lines.

So back to my original questions.

Does a 145 injector in 9mm exist in a 5x.010 or 5x.012?

Are there selective thickness 7 to 9mm sleeves so I can try injector height changes to see if it affects the haze?
 

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To my knowledge, no. The 9mm head was the early models and was changed to 7mm. The P pump engines that came along in the early to mid 1990's had 7mm heads. I honestly don't believe your engine originally came with a 9mm head but can't verify that.

I did some research on the heads. A CPL 0858 and a CPL 0767 which are common early engines have the following head numbers. It would have been a 9mm head to begin with.
3913389
3933416
3910275
3927296
3927298
3929736
3930913
3967444
A CPL 1839 which is the P Pump model and used the 7mm head from the beginning had the following numbers.
3927330
3967430
A CPL 1260 like yours shows the following head numbers.
3920394
3927330
3967430
As you can see, none of the numbers match to the early 4bt and I have no idea why. I suspect the issue is who made the heads and a different part number was assigned depending on the manufacturer. We know the CPL 1839 was a 7mm head from the beginning but there is one number in the CPL 1260 that is different and I don't know why. If you wanted to see which head you have I believe that part number is inside the intake area. The head number 3920394 which was on CPL 1260 was preceded by part number 3910275 which does appear in those early numbers and that one is 9mm. Cummins would have to check the engineering specs to see what size injectors were on what head part numbers. No such detail are included on Quick Serve.
 

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1. I am running the 7mm x 9mm adapter sleeve to install these injectors but the thickness of the "washer" part seemed thick. As in I think the injector is high in the head. Do they make selective thickness adapters like they do for the copper washers? PN and source?

2. I can't find a 145 deg nozzle in 9mm configuration in any cross references. Does anyone know if these exist and if so nozzle part #s in a 5x0.010 (145)(9mm) and a 5x0.012 (145)(9mm)

3. If I can't find some 9mm options I will go with Bosch genuine 7mm. It seems like everyone will sell you injectors for $100 each, but I kinda just need the nozzles. I have not been able to find a good cross ref for 5x.010 or 5x.012 145 deg nozzles. I did find a few on chinese knockoff sites but am going to stay away from these. Anyone have a good xref on nozzle PN.

4) Should I go with the 6x.009?

5) Any other suggestions as to a path to try or to diagnose why I am hazy with these tips?

TLDR my 5x0.010 chinese unmarked nozzles suck and haze and looking for options
1. I had the same issue with my 7mm to 9mm sleeves. I chucked each adapter up in the lathe and cut the washer part down to match the bottom of washer-to-nozzle-tip distance as the ones I took out. Didn't find selective thickness 7-9mm washer/adapters anywhere.

2. Not that I know of. 145* nozzles were all intercooled (duh) motors and by then all the heads had been updated to 7mm injector nozzles.

3. DFI sells injectors and nozzles. They supply for lots of companies like PDD. Ducky Fuel Injection This is where I bought my recent set from.

4. More nozzle holes with the same total cross sectional area will atomize fuel better. Give it a shot.

5. Nope. Mismatched nozzle spray angle to piston bowl diameter will cause this problem.
 

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Discussion Starter · #6 ·
Hey thanks Johnny. I was thinking the exact same thing on running those adapter sleeves in a lathe to take the shoulder down some. As best as I've found the copper washers came in a .030, .060, and a .090 thickness and the shoulder on the 7x9 sleeves are a nominal .060. I was worried if you went too thin the sleeve could separate from the shoulder under operation and drop the sleeve into the cylinder.

I think I have a lead on some genuine Bosch 5x.010 nozzles. Stay tuned.
 

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I didn't have to thin my 7-9mm adapter washers much to get them to be the same stick out as the ones I tool out. Didn't think they were so thin that they would fall apart. Hasn't happened yet either, lol.

I got marine 370s, meaning 5x12s with a 155* spray angle. They're pretty rad with my new compound setup and non IC pistons.
 
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