SmokinCAT
Cheap and Easy.
- Joined
- Sep 13, 2008
- Messages
- 3,162
Was that Tony?
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.
Was that Tony?
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.
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.
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 can tell you a good friend of mine runs injectors that flow around 220cc and his truck did 562hp to the tires.
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?
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:
I'd imagine that the ramp rate is going to get very important at that fuel flow and 3500rpm.
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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.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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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.