Sorry, I didnt realize you model was Z-Axis aligned.
Try it with this line
"vec_set(particles_dir, vector(2,2,5)); //or -5 // length of spray"
instead of your
"vec_set(particles_dir, vector(-5,2,2)); // length of spray"

You can see how Ive just rotated the jets direction around to the z axis.
The particles_dir is the particles intital direction (and sizesince you are using BEAM).
So by setting its Z vector high, jet sprays in that direction.