Wait, 25000-35000?!?!
Where are you gettin your info?
We don't even get that at the nozzle, after the intensifier piston has amplified injection pressure...
Try 3000, maybe 3300 in a spike, inside the top of the injector.
And IF everything inside that injector is in good shape, about 21000 at the nozzle.
And several thousand times a minute? Try a bit south of that, even at redline.
They're loud, especially at idle, because they're running at about 3500 psi AT THE NOZZLE. No injection quality. The HEUI characteristics of the injector don't help either.
They just dont realise that your 99 has the single shot injector while ours has the split shot. My friend and i were talking about that just the other day...
:doh::doh:
50 state trucks stopped putting single shots AA's (90cc) in the truck in 96. Starting in 97 Cali trucks through the E99's, had AB injectors (130cc).
ALL 8 injectors on an E99 are AB code. AB code injectors are ALL split shots. The reason an E99 will sound louder than a 2000 is because it does not have a "long lead" injector in the number 8 cylinder.
Firing order on a 7.3 is 1, 2, 7, 3, 4, 5, 6, 8. Front to back on the drivers head, 2, 4, 6, 8. Passenger head front to back, 1, 3, 5, 7.
The fuel rails on ALL superduties fed from the front in factory form. So, the number 6 cylinder fires immediately before the number 8 cylinder, starving it for fuel, further degrading injection quality, increasing noise.
So, in 99.5 when they swapped to AD code injectors (140cc Split Shot) they incorporated a "long lead" (AE code) injector in the number 8 cylinder, to quiet this noise...