Tuning for single shots
 

A guy at the shop has an '02 that we are looking at putting 160/30's in. Is it all timing changes or is there more to it?

Roger

Little bit timing, the biggest change is in PW (dropped).

Here it the PW maps comparing the two, splits on the left.


http://i619.photobucket.com/albums/t.../untitled4.jpg

Um, big difference! Are those stock maps or maps from tunes?

Stockers.

Looks like from the graph of the single shot that anything ICP pressure over 13 MPa doesn't have any effect on flow or Pulse width.

Pretty much!

As long as the load (MFD) stays the same PW remains constant throughout the ICP ranges.

duplicate post

Because the injectors can only deliver so much fuel on the OBS trucks and Ford didn't "push" the injectors very hard on the older HEUI system (where that map came from). That's why the pedal feels "dead" after half throttle or so :rolleyes: .

Makes good sense.

Cody, would you say those injectors are pretty much maxed out, or is there any room for improvement via tuning?

The AA's?

I've got mine maxed out on my 95 right now. The accelerator pedal feel is AWESOME, but anything past about 1/2 throttle at 2000 RPM+ is dead space. I'd call it 60 HP by the seat-o-the-pants dyno. Basically, all you get with tuning on the OBS trucks with stock injectors is fuel down low and more power before 2000 RPM. Not saying that there are no gains above 2000 RPM because that isn't the case. With some SOI and injection pressure, you get gains up top, but it's nothing to write home about.

I have always felt that the Powerstroke's just seem to level off around 2/3 throttle anyways, with stock sticks.

Is there any explanation for this, or just a injector volume thing?

The proverbial nail on head.

AC's can solve that with some tuning though. Lots more volume.