Local diesel emissions place claims my Excursion is only developing 210hp, when last year it was over 260, in "stock" tune. Smoke this year was 3%, last year it was 5%. This year I have a live tuned F5, last year *I think* I had the chip out. I did a little test today and the stock tune will get up to 19-20psi of boost pressure, in the same place my live-tuned 60e will develop 23-25psi. The truck runs fine, I think, in the 60e and tow tunes. Stock tune seems like a slug, but don't they all?

Does it make any sense that DP's stock tune would be substantially less powerful than the OEM stock? (PMT2, if that matters)

A couple of things:

1) I live at 5400ft which lowers boost a bit, compared to you flatlanders.
2) This shop uses emissions testing to sell stuff. (e.g. They marked my oil condition as "poor". It's Rotella T6 with 5300 miles on it. I'm guessing it's fine.)

Mark

 

How are they determining the power level? Do they put the truck on a dyno for the emissions test? If so, is it calibrated correctly?

 

They do put it on a dyno, but who knows how well its calibrated.

Mark

 

Would your stock tune be a Modified stock because of the T500? I know my stock tune is not exactly "stock" because it compensates for the ss injectors.

 

not to be rude but who cares what stock is doing?

I can't remember the last time I was in stock...

 

I use stock on every drive.

• It's quieter in resedential neighborhoods where there are steep hills.
• I can hear the whistle better when in town.

If the truck is "weaker" in stock this year with the differences you listed, there is more than one possible explanation:

• The DP stock tune could be weaker in your truck than the tune on your PCM. The DP stock is a copy of the original tune, with adjustments to the shifts to make it healthier for the transmission. This alone could make a HP difference, but I don't know enough to say. Unless you are the original owner, it's also possible the PCM was reflashed at some point in its life, so it wouldn't be original stock.
• Something may be a bit "off" with the truck since your last emission test. HPOP, EBP, MAP sensor, injectors, etc....
• A dyno day was conducted near me not long ago, and the numbers coming out of that machine sounded absurd to me and a few other members. If the dyno was correct, I could assume I'm getting near 400 HP with the configuration in my sig. I don't think so on so many levels. If that machine can be that far off, what's 50 HP in calibration difference? Maybe the machine is calibrated now, but it wasn't a year ago. Maybe it was 25 HP high last year and 25HP low this year. 210 HP in stock at your elevation is not completely out of reason. 230-235 is even more reasonable for both dynos.

$0.02

 

I can tell you from tuning my Grand National the different types (manufacturers) of dyno's can easily make a difference in your RWHP...was it a Mustang dyno by any chance?? Their known as the "heartbreaker" dyno's because they give very humble numbers Also, was the emissions center really doing a full pull in 3rd gear to test for max HP? Maybe last year they gave it a true pull!

 

Not rude at all. Strictly speaking, I don't care, either, unless it's a data point that tells me something else about how the truck is working. My original thought was that DP's stock might be different than Ford's, though that doesn't look to be the case, other than changes for the BTS, etc.

It is possible the old stock wasn't really stock, as the original owner used a HTIII programmer, which I didn't get. I think the program was removed, though, as the overhead mileage display was dead on for the 60K miles prior to adding the chip.

I don't know the emissions testing protocol, but I thought of one other change since last year that might have had an effect: I used AE to recalibrate my speedometer, as the tires I had on was causing it to read about 3mph slow at 75mph. If they are using the speedo, they will have less fuel at the same indicated speed than last year, and that would translate into less power and less smoke.

Of, course, dyno accuracy can't be discounted. The testing here is such a joke that a dyno could be off by a lot and have no effect on pass/fail rates.

Mark

 

To the best of my knowledge when you have a "stock" tune, it just sets it in a copy of the ford PCM. Perhaps your actual PCM and the "copy" on your chip are different. Your PCM might be an updated version. Over the years Ford did up the HP on the 7.3,

 

Jody definitely used to make changes to stock. I have been out of the loop for a while, but I would be shocked to find out that he is NOT changing his stock tune. That being said, my stock tune seems like it has more power and much better shifting than the original 2003 programming.

 

My stock tune behaves the same way. And I have to do the yearly emissions dance as well. It always passes with flying colors.

 

Chris, do you have yours tested in stock tune, or another one? IIRC, the opacity limit is 30%, and mine is always around 5% or less in stock. Had I thought about it, I'd have had them test my DD tune.

Mark

 

I always had my emissions test done at Schwinzell's Diesel in Fort Collins and I never saw a HP number on the sheet.