General waste of my time

Yep, he hadn’t had any issues until he switched to a big injector, let him carry a lot more rpm down the track and then he started having issues with it.

Do you know what brand pump he is running? Do you think it is worth trying the cummins pump? Don't want to spend $1k on a pump that will only make one pull.
 
So what's it take to go to a different injector and p-pump on one of these engines?
 
So what's it take to go to a different injector and p-pump on one of these engines?

Ummm... A lot! And a lot of experimenting.

Cyclone machine does make an "adapter" to a pump drive for a pump, injector lines and machine the heads. But in my mind its not worth the effort. You lose the air compressor and it still wont compete with the Cats and the K motors.

You're money, time and effort ahead swapping power plants.
 
Ummm... A lot! And a lot of experimenting.

Cyclone machine does make an "adapter" to a pump drive for a pump, injector lines and machine the heads. But in my mind its not worth the effort. You lose the air compressor and it still wont compete with the Cats and the K motors.

You're money, time and effort ahead swapping power plants.

That's not sounding horrible for my potential application, to be honest.

I don't have to compete with Cat's and K's, I don't need a air compressor, making drive adapters and couplings doesn't make me flinch.

I guess I'm mainly curious about the injector. I've got some ideas on what I would do.

I'm brainstorming at this point. It seems that a 855 would do what I want, and be far cheaper than a Cat.
 
That's not sounding horrible for my potential application, to be honest.

I don't have to compete with Cat's and K's, I don't need a air compressor, making drive adapters and couplings doesn't make me flinch.

I guess I'm mainly curious about the injector. I've got some ideas on what I would do.

I'm brainstorming at this point. It seems that a 855 would do what I want, and be far cheaper than a Cat.

I have no idea what the injector cup looks like for a Bosch injector in an 855 head. They don't seem to live to long in a pulling application. What kind of power levels are you looking for? Why can't the PT fuel system get you there. I can't give you HP numbers (Cody can), but there are some pretty high HP 855s from the factor.
 
I have no idea what the injector cup looks like for a Bosch injector in an 855 head. They don't seem to live to long in a pulling application. What kind of power levels are you looking for? Why can't the PT fuel system get you there. I can't give you HP numbers (Cody can), but there are some pretty high HP 855s from the factor.

North of 1500 would be preferred. 2000 would be even better. Big single charger.

I have no idea if the PT is a reasonable option at that level. I have in mind to sleeve the injector bores in the head, use a 8.3 injector body, install a 24V dodge nozzle on it, and work out the dimensions to get protrusion/bowl diameter/spray angle happy. This is all somewhat theoretical at this point, I need to get my hands on a set of heads and see if the numbers work.
 
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Curious to know what your scheming.

I think 1,500 hp to 2,000 hp would be tough on the PT system of an 855. Need a long stroke injector and most likely a custom ground cam shaft to get the needed injector lift. Good luck finding anyone to grind you custom cam for an 855.
 
I will let SmokinCat release whatever info he wants. I can tell you if you are talking flywheel hp then he is around your current hp target.

On edit: This is my opinion based on things that have been said previously. He has not directly told me his estimated hp. Other than definitely north of 1K
 
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I can tell you a good friend of mine runs injectors that flow around 220cc and his truck did 562hp to the tires.

That was posted earlier in this tread. The injectors I am currently running are around the 500cc area. SmokinCat is now running a set that are much larger than what I have.

That alone should give you a little idea of what the pt system is capable of. Much more fuel than an 88mm charger will handle.
 
Curious to know what your scheming.

I think 1,500 hp to 2,000 hp would be tough on the PT system of an 855. Need a long stroke injector and most likely a custom ground cam shaft to get the needed injector lift. Good luck finding anyone to grind you custom cam for an 855.

Heavy hot/open/modified farm tractor, in classes where they don't really care about the engine.

I would think Vogel or Colt would grind it, but I assume others have already looked to them with no luck?
 
Heavy hot/open/modified farm tractor, in classes where they don't really care about the engine.

I would think Vogel or Colt would grind it, but I assume others have already looked to them with no luck?

Its not that people haven't looked into it, it is finding someone that wants to work with you on the idea, the 855 cam isn't just valves that need modified, injection timing, length of injection, as well as lift are all factors and likely more important than the valve lobes in the long run.

Finding the right person that knows how to modify the injector lobe for the better is really what is difficult.

I run a later STC cam, the ramp length is too long and the injection is lazy even though it has a lot of travel, the ramp could be modified but even then who knows how much to shorten it to get the ideal results.
 
Its not that people haven't looked into it, it is finding someone that wants to work with you on the idea, the 855 cam isn't just valves that need modified, injection timing, length of injection, as well as lift are all factors and likely more important than the valve lobes in the long run.

Finding the right person that knows how to modify the injector lobe for the better is really what is difficult.

I run a later STC cam, the ramp length is too long and the injection is lazy even though it has a lot of travel, the ramp could be modified but even then who knows how much to shorten it to get the ideal results.

Not to sound like a smart @$$ but is the injector lobe really that hard to figure out? I am sure there is a lot more to it that is way over my head.

In my way of thinking if you know the injector cup size and area of the plunger. From there you should be able to do some math on plunger speed to maintain desired injection pressure. Then it is the matter of figuring in valve train ratios all the way to the rocker boxes.

By no means a walk in the park. But one would think that someone that builds custom ground cams should have the capability to do said calculations?

Ignore everything I just typed if I am off my rocker :blahblah1:
 
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Not to sound like a smart @$$ but is the injector lobe really that hard to figure out? I am sure there is a lot more to it that is way over my head.

In my way of thinking if you know the injector cup size and area of the plunger. From there you should be able to do some math on plunger speed to maintain desired injection pressure. Then it is the matter of figuring in valve train ratios all the way to the rocker boxes.

By no means a walk in the park. But one would think that someone that builds custom ground cams should have the capability to do said calculations?

Ignore everything I just typed if I am off my rocker :blahblah1:

I'm sure it is possible and there are plenty of guys more than capable of doing it. But for who? This is a dinosaur that is no longer in production, not many on the road (all things considered) and even less looking for more that what the factory components can produce. Time, effort and dollars dont make since.

I'm sure if you walked into a machine shop with all of the grind specs they'd do it. But you'd be doing all the leg work.
 
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I'd imagine that the ramp rate is going to get very important at that fuel flow and 3500rpm.

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I'd imagine that the ramp rate is going to get very important at that fuel flow and 3500rpm.

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I think it is more important for atomization than a lot of people would let on.

Higher RPM could focus a lot on fill time, but on the same line you dont want fill time too long or injector could start dribbling on its own, and that is a good way to put a hot spot on the top of a piston.
 
I think it is more important for atomization than a lot of people would let on.

Higher RPM could focus a lot on fill time, but on the same line you dont want fill time too long or injector could start dribbling on its own, and that is a good way to put a hot spot on the top of a piston.
5-600psi of rail would have to be hard on push tubes if it ramps up too fast as well. I really only know an outline of the pt system so I'm just kind of guessing.

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5-600psi of rail would have to be hard on push tubes if it ramps up too fast as well. I really only know an outline of the pt system so I'm just kind of guessing.

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Good thing about a lot of the newer injectors being built for performance apps is that they are making them so they don’t need the high pressure like a stock part injector to get the same performance.
 
Good thing about a lot of the newer injectors being built for performance apps is that they are making them so they don’t need the high pressure like a stock part injector to get the same performance.

How is this? Just curious.
 
I came by that knowledge through my injector builder, it is one of his part design features and not something that he wants everyone knowing.
 
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