I just got my truck dyno'ed and it's running slightly leaner than I expected for a "stock" motor. The Air/Fuel was determined by the dyno computer, not by a wideband gauge. Does this seem stock?

Dyno Result:
363 hp/422 tq
12.78 AFR
74F, 32% Humidity, 350 ft above sea level

As far as I can tell, there's been no pulley swaps. The most boost I've seen is 8 lbs based on the stock gauge. Intake is stock. Exhaust is stock. Are the Ford ECU's programmable or do you need a piggy back chip to thrown on custom tunes? I checked the ECU and didn't see any visible add-on chips...maybe I don't know what I'm looking for?

 

theres flash tuners.
www.sctflash.com is one.

 

If I got a flash tuner hooked up, would I be able to tell if it has a stock tune?

 

that ones beyond me honestly. i dont think so. sound like you just picked this truck up, have you gone over it looking for mech / vac problems?

 

Was it just dynoed to check the power, or was it actually tuned? If it was tuned, you should either have a chip on the PCM, or they would have sold you a $400 flash tuner that you keep when done.

Your A/F is way too lean though, you need to have it dropped down a full point to about 11.7. If you are unsure of what the shop did, you might want to try another shop that is known to be reputable. Where are you located?

 

I'm in San Diego.

I got it dyno'ed to see if it really was stock and just to get a baseline for future modifications. I don't see any obvious mechanical problems. It's an 03 with 29k miles on it so I don't think the hoses could have gone bad. Of course I wouldn't know if I'm losing boost anywhere if I had a pulley swap...but that would seem a little silly to do if you still maintain stock intake and exhaust.

I really just want to keep this stock for a couple years. And if the time ever comes for more power, I'll swap out the engine.

 

hp/tq numbers seem relatively normal for an 03. I would say find someone with a wideband or purchase your own to check the true A/F ratio. I am unsure if i would trust the dyno's computation.

 

I planned on getting a wideband but I guess I'll be getting one sooner than planned. I'll dyno it again and see how things really are.