So I had an issue with an injector during my cam swap. While I was installing my pump and lines, I stripped out an injector body...

While being an annoyance, that isnt the point of this thread, the stripped threads have nothing to do with the function of the injector... However, I had to pull apart the injector to swap bodies with all the "working" parts...

First thing I noticed after pulling the injector out, was the carbon build-up on the tip, and its corresponding pattern... It wasnt even around the orifice... Now at first I thought that it might be because of the swirl in the Pre-chamber, but as I thought about it, I dont think with all the turbulance in the chamber, that carbon could build like that in that spot, it has to be because of spray pattern... (I wont know until I test them on a pop tester)... So I pulled the injector apart. I was suprised to see what the pintle looked like... It was almost like it was burned, or got "hot"... Only explaination I can come up with, other than it being screwed to begin with, was 6.5* of timing and 150cc's or fuel, and the cylinder pressure pushing the combustion back into the injector, because of too low of a pop pressure......dunno... However, Im pretty sure that the stg 1 injectors ken sold, were not a precision product, and that the pintles were probably not cut properly... Probably most likely on a bench grinder. As a machinist, I know that this can lead to a non-perpendicular tip, and probably why Kens injectors are so hit and miss... I like the idea of the DPS injectors, because it does make sense, however, A) the pump is going to get whatever amount of fuel it pumps past the injector no matter what, and B) if you dont have the right machining practices, its going to result in poor performance... I think that DPS injectors could be done the right way, and I just might experiment with that here... Well see.

Anyway... Here is some pics...