Single shot injection?

[Stroked777]

As soon as I free up some money I'm gunna start to do my own tuning. I was gunna get a MCC file from Matt at gearhead, but anyways I remember seeing some where about someone talking about single shot injection and was wondering if anyone runs a file with it and what the pros and cons of it are. Thanks

 

[powerstroked08]

I just started to make a tune with this type of injection setup. I was hoping it would free up some fuel to maybe run bigger injectors. Its my understandong that the pilot injection is mainly for emissions and sound reduction.

 

[MrMike2010]

I was doing some research into this not long ago. Basically I read up on some dmaxs and they found that not only do cylinder pressures spike with pilot injection removed you have to play with the timing too. Not positive but I think you would have to pull injector timing back. I'm not sure I would mess with this unless I had some sort of way to monitor cylinder pressures. Although if someone made a safe tune I would love to run it here and there. I do miss the sound of my old 6leaker.

 

[powerstroked08]

Well that kinda sucks. :fustrate:

 

[Highroller54]

I miss my noisy old six liter as well.

 

[Stroked777]

I miss my noisy old six liter as well.

Lol who doesn't? I like being able to tell my truck is running
Going back to someone talking about the cylinder pressure spiking on single shot, I don't see how a 6.4 couldn't handle the pressure spike even with a single pilot injection cycle,

 

[powerstroked08]

Well the pilot injection stops at around 2500 I think but I'll have to make sure

 

[WoodBoy]

I think its alot lower than that when cold

 

[Dieselfever]

Either way there are tables for "Pre injection quantity" and "Pre injection timing". I'm thinking you would set the quantity tables to "0" across the board, I'm just not sure if the timing would still mess with things, if so you would have to play see where it needs to be.

The next thing is adjusting your main injection quantity and timing. Obviously with the pre injection gone the way the combustion happens is going to change. Just guessing I would say both main injection quantity and timing would have to be slightly increased. Your best bet would be to watch cylinder pressure with pilot injection, tweak for single shot injection then watch cylinder pressure again and go from there.

 

[Dieselfever]

I just went back and looked, there are 2 Pre Injection activation tables under Injection Quantity also, maybe set them to 0 is what is needed to switch to single shot injection

 

[powerstroked08]

Yeah i see the same thing, i just wonder if we drop the the quanity some, say half and run it just to keep the pressure spikes to a minimum. I think it might keep some more fuel in the rail and maybe still keep the cylinder pressure in a safe range. Just something i have been pondering.

 

[Buffalo444]

Someone should do this and post up videos... with both stock twins then a single...

 

[powerstroked08]

Does anyone know what the bowl size is of a 6.0 piston? Just curious if there is much differance because the 6.0 doesnt have preinjection. So if the bowl is the same the pressure spikes might not be too bad as long as the timing isn't way differant between the two.

 

[powerstroked08]

I do believe the compression is the same in both the 6.0 and 6.4 but i'm not sure if the bowl design is any differant.

 

[MrMike2010]

You guys got me thinking on this. I'm just not smart or brave enough to test this out due to my lack of tuning skills.

After reading a little more, the dmax and cummins guys who removed pilot injection advanced the timing slightly to clear the white haze. Sounds like they just shut it off all together, tested the tune, noted where it hazed thed bumped the timing up slightly till it cleared. Google "remove pilot injection" and numerous posts will come up with some pretty good info.

As for pressure spikes, without pilot injection it's probably very similar to what a 6.0 would have, maybe slightly greater since the timing will be off until that gets tweaked too. The spike in pressure is actually what give a diesel it's knock, cackle or whatever you want to call it. I am by no means a diesel tuner just been reading up a little to share some insight.

 

[Buffalo444]

Does ANYONE have videos of this on a 6.4? The only thing I can find it on is a 6.7 cummapart...

 

[Stroked777]

I would think the 6.4 can handle it. A 6.0 is 18:1 compression and the 6.4 is 17.5:1. One would think that the 6.4 could do it due to less compression and a lower over all cylinder pressure, that's my two cents

 

[powerstroked08]

I would think the 6.4 can handle it. A 6.0 is 18:1 compression and the 6.4 is 17.5:1. One would think that the 6.4 could do it due to less compression and a lower over all cylinder pressure, that's my two cents

Ok i thought they revised the 6.0 to 17.8 or so in the later ones but im not an expert. I just wish i knew if the piston bowl is the same or similar as to know how the 6.4 will react to it. I dont think that it will just flat out destroy itself but it would just be nice to have an idea how it will react.

 

[Stroked777]

Ok i thought they revised the 6.0 to 17.8 or so in the later ones but im not an expert. I just wish i knew if the piston bowl is the same or similar as to know how the 6.4 will react to it. I dont think that it will just flat out destroy itself but it would just be nice to have an idea how it will react.

from what i can recall from memory the pistons are the same design maybe someone like a vendor they has both a 6.0 and 6.4l stock piston in stock can compare them and chime in

 

[Stroked777]

If not single shot,maybe a single pre injection shot like a 6.0? Would that help the spike? And how many pre injection shots does a 6.4 do per stroke ?