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Injector Nozzles

I have stock nozzles set at 2600 psi currently. The only reason I went back to stock nozzles was because it wanted to haze at idle. This was the Monarch nozzles set at 3200 psi,it would lope slightly also. At lower psi it wouldn't lope,but still haze the same. I did notice that higher psi narrows the spray pattern considerably. And around 2500 psi seems to be a happy medium.
 
Maybe it won't help any decision making, but I just installed a set of 2300psi injectors, and they made a noticeable difference. It definitely has a bit more low end grunt and responsiveness. Starts cleaner and smoother. Runs a bit cleaner during driving. A nice step from my old wore out injectors. And it doesn't surge anymore at 2600rpm. So nice
 
yeah I don't think the pattern being tighter will hurt anything because the pressure hits the precup which swirls the fuel, so the more pressure the more movement of the fuel or better atomization. I would love to have more low end, with the diamond cups, porting and correct adjustment of the turbo it really helped the bog between 3nd and 4rd with the nv4500&3.73s however more improvement would be nice.

Also when the turbo is adjusted to spool quickly the downside is more drive pressure. However I plan to fix this with a switch in the cab controlling another actuator. Ill be using pneumatics unless someone has a fuel shut off solenoid for sale at a good price.

Anyways lets not get off topic :hihi:
 
I forget do the 6.2 marine nozzles fit the 6.5 body? and are the 6.2 marine nozzles the same as the 6.5 Bosch marines?
The 6.2 nozzles are out of a 1 ton military truck 85-87 N/A of course
 
yeah I don't think the pattern being tighter will hurt anything because the pressure hits the precup which swirls the fuel, so the more pressure the more movement of the fuel or better atomization.

If the fuel isnt dispersing in a wide pattern it may not be getting a good mix, and if in a tight pattern the droplets could rejoin. When the precup is pressurized at 2000psi I dont think much swirling is going on until combustion starts and it starts expanding into the cylinder, thats when the mixing is really going on. Thats why a larger precup can make more power because it can expand into the cylinder faster and making more complete and faster combustion higher in the power stroke where there are better angles to the crankshaft to make torque.

I forget do the 6.2 marine nozzles fit the 6.5 body? and are the 6.2 marine nozzles the same as the 6.5 Bosch marines?
The 6.2 nozzles are out of a 1 ton military truck 85-87 N/A of course

If they are short body and fine threaded should be the same body #0430211054 and fit, but may have a different tip in them, and I dont know that there was a 6.2 marine specific tip/nozzle, I think they used Bosch OSD253 in all of them with the same body as 6.5s which used nozzles OSD304 and 311
 
If the fuel isnt dispersing in a wide pattern it may not be getting a good mix, and if in a tight pattern the droplets could rejoin. When the precup is pressurized at 2000psi I dont think much swirling is going on until combustion starts and it starts expanding into the cylinder, thats when the mixing is really going on. Thats why a larger precup can make more power because it can expand into the cylinder faster and making more complete and faster combustion higher in the power stroke where there are better angles to the crankshaft to make torque.

Good Thoughts!

If they are short body and fine threaded should be the same body #0430211054 and fit, but may have a different tip in them, and I dont know that there was a 6.2 marine specific tip/nozzle, I think they used Bosch OSD253 in all of them with the same body as 6.5s which used nozzles OSD304 and 311

I thought they had a marine tip just for fixable fuel choices and I thought they used the long ones until they came out with the turbo engine due to clearance issues. I was just thinking about using the tips in them to save some money but I'll probably have to find some real bosch marine ones. The only place I know of is ebay for 130 dollars.
Maybe someone knows a place a little cheaper :)
 
yeah I was gonna go with the bosch unless you guys think it doesn't really make a difference
Bosh: 129.99 free shipping
Knock offs: 76 with free shipping
 
Buddy- I'm guessing you don't know that cummins, perkins, and yanmar also used a stanadyne pump, same as the 6.2, just not as many cylinders. The cummins and perkins engines that I tested had pop pressures between 3300, and 3800. The yanmar I saw was on the job, so of course I didn't get pop pressures tested.
Just maybe an eight cylinder rotary pump is not reliable delivering the same pressure as a six cylinder version. In the eight cylinder version everything in the high pressure section is closer together, less metal, less room for sealing and so on. I do believe a DB4 is bigger than a DB2 in the head area, with out going out and looking under the hoods of the trucks.
 
Just maybe an eight cylinder rotary pump is not reliable delivering the same pressure as a six cylinder version. In the eight cylinder version everything in the high pressure section is closer together, less metal, less room for sealing and so on. I do believe a DB4 is bigger than a DB2 in the head area, with out going out and looking under the hoods of the trucks.

Well and if they are in the similar RPM band then a 4 cylinder pump's plungers and metering valve move back and forth half as much, so the few moving parts that are most likely to wear should last twice as many miles.
 
Just maybe an eight cylinder rotary pump is not reliable delivering the same pressure as a six cylinder version. In the eight cylinder version everything in the high pressure section is closer together, less metal, less room for sealing and so on. I do believe a DB4 is bigger than a DB2 in the head area, with out going out and looking under the hoods of the trucks.
the one thing to consider is that with any db-4 the max plunger size is .310", there is not enough meat left in the rotor to accept anything bigger.... and head and rotors from 6 cylinders are not compatible with 4 and 8 cyl, models....
 
Turbonator I remember you talking about some of the mods you do to the pumps you use, can you share? :)

I still sometimes wonder why people need more fuel then the 4911 puts out because I have always ran a 6.2 pump turned up and have always had more fuel then I needed along with way more adjustment room. Is it all about fuel flow or are there other things you do to them?
 
We kind of just follow the lead that others have tried recently with these pumps to increase the fuel flow (volume ). The housing of similar DB2/DB4 pumps are the same size. The head (rear-most section), which the lines attach to, is the fuel distribution. The rotor, which the plungers are in, is the high pressure section and fuel is just transfered to the head, by the matching up of corresponding ports as the rotor turns. The rotor from a DB2 and DB4 are the same size and interchangeable, the fitting with the head is very close tolerances though and Stanadyne usually only sells the head and rotor as an assembly. I believe 6.2turbo has used a 4 cyl rotor (larger plungers) with one of our 8 cylinder heads and body. The 8 cylinder head, AFAWK, was only used with the GM and Ford automotive applications. The 4 plunger pumps, were used in many applications, but as of yet have not seen any with the plunger size above .310". Even with the .310" plunger in a DB4 pump, two of the plungers are sometimes bevel cut for clearance issues. We have more Stanadyne data coming, in which we will be able to compare parts #'s, to have a better idea what all was changed between one pump and another.

This is getting a little off thread direction, if someone would like to start a DB2/DB4 mod specific thread, we will participate and share all the info we have. In this, there are those whom have tried many more things than we have and we will be able to learn much more.
 
We kind of just follow the lead that others have tried recently with these pumps to increase the fuel flow (volume ). The housing of similar DB2/DB4 pumps are the same size. The head (rear-most section), which the lines attach to, is the fuel distribution. The rotor, which the plungers are in, is the high pressure section and fuel is just transfered to the head, by the matching up of corresponding ports as the rotor turns. The rotor from a DB2 and DB4 are the same size and interchangeable, the fitting with the head is very close tolerances though and Stanadyne usually only sells the head and rotor as an assembly. I believe 6.2turbo has used a 4 cyl rotor (larger plungers) with one of our 8 cylinder heads and body. The 8 cylinder head, AFAWK, was only used with the GM and Ford automotive applications. The 4 plunger pumps, were used in many applications, but as of yet have not seen any with the plunger size above .310". Even with the .310" plunger in a DB4 pump, two of the plungers are sometimes bevel cut for clearance issues. We have more Stanadyne data coming, in which we will be able to compare parts #'s, to have a better idea what all was changed between one pump and another.

This is getting a little off thread direction, if someone would like to start a DB2/DB4 mod specific thread, we will participate and share all the info we have. In this, there are those whom have tried many more things than we have and we will be able to learn much more.
 
hey guys how did you remove the waxy material on the bosch nozzles? I was thinking a propane torch or some rubbing alcohol.
 
I was able to peel it off mine. used my fingernails to scrape the tops off and then pull the rest off the bottom kinda like pulling a sock off..... there was still some stuck in the three holes on the top so I soaked them in mineral spirits for a while then carefully pulled the pintle out and blew the nozzle out with a rubber tipped blow gun, some were stubborn but they all cleaned out. I re assembled them with corn oil to ensure they were lubed...
Hope this helped...
 
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