With the 100hp setting on my Predator at full throttle I get the same cackle I would hear at about 1/4 throttle. Before when I would drive the sound would be there untill the boost came up and then it would be as quiet as a jet. Now it will still do that but when I stand on it the noise comes back. It's as if it is pinging as a gasser would. The smoke is black to gray but I have never changed the fuel filter now at 21,000. Any ideas????

 

Injector rattle. Happens alot with high HP chips with a little timing in them.

 

The only noise an injector makes is a ticking that sounds identical to a faulty hydraulic lifter.
The only thing a chip can change that could change the sound of the injector is the oil pressure, but that's pretty unlikely. If the oil pressure is that high, the engine will idle very rough, like with a 10k mod.
I think what you're hearing is cylinder knock from excessive timing advance.

 

It does seem to be timing. Should I be concerned about this? Do I need to run a cetane addative to keep things good?

 

Which gets progressively louder as the pressure and pulse width are cranked up.......injector rattle.

 

I get the same thing on the extreme positon on my chip. Mainly went I get on it hard then let off, it'll rattle like a choppy idle for a little bit then settle to a kinda high idle.

I had the same concern you as you, I talked to Dave at DI and he said it was perfectly normal and will not damage anything. My understanding is that a hot program (chip) opens up the ICP and raises the oil pressure a lot. When you are on a hot run and you let off, the computer goes into deceleration mode and shuts off the injections, but oil pressures in the system are still so high that it accually forces the injectors open untill the pressure is bleed off.

Hope this helps

Nelson