2002 7.3 Powerstroke boost?

The friendliest place on the web for anyone with an RV or an interest in RVing!
If you have answers, please help by responding to the unanswered posts.


Well-known member
Dec 4, 2010
Buckeye, AZ
I just bought an F350 crew cab dually and it has a Superchips sticker on the fender but the dealer I got it from said they got no info on it when it was traded in. Pulling my trailer wide open throttle uphill in drive for about 1/2 mile, boost pressure stabled out around 26psi and EGT was around 1150-1200. My question is, is that close to stock boost numbers? I think they might have set it back to stock before trading it in and just didn't want to bother with removing the decals?????????

My uncle has the same truck with a superchip installed and on performance mode he can hit 30-31psi. But I'm not sure since all trucks could run a little different and we have different gauges.

Is my truck stock or chipped?
A simple scan by the dealer should be able to determine if the truck has stock or aftermarket tuning.  I would normally expect a dealer to perform such a scan as part basic best practices prior to allowing a vehicle to be sold. :)
I guess "used car lot" would have been the best term for me to use, it wasn't really a Ford dealer. I'm taking it in tomorrow anyways to have some work done so I'll just have them add a diagnostic scan to the list.
Good idea to have them scan.  Do not allow them to modify (only scan) until they confirm the chip is the stock issue.  Sometimes a third party programmer will will code any changes so that dealer modifications create problems.  If they cannot obtain a normal scan reading chances are good that a third party chip or modification has been installed.  The other way to tell is to locate the chip and take a physical look at it.  Most third party chips have a logo applied to the chip itself, (unless it is a stock chip that has been modified and re-installed).
I have a 2002 7.3. I do have the " Superchips" mod in my unit. It is NOT a chip. It is a reprogrammer that plugs into the diagnostic port of your engine computer. It is also sensitive to the serial number of the "magic" box reprogramer used to set up the desired performance. If you are satified with the performance just leave it alone. If you think there are problems it will need to go to a dealer and be reprogramed with the factory program. The programmer has 4 choices, mild, medium, maximum and stock.  My personal preference has and is the medium setting. I originally used it to boost performance while towing a trailer. The trailer is now gone but I am satisfied with the performance so I just left it as is in the medium mode and use it as a daily driver.  It has been in use for 7+ years now with no problems. You might try contacting Superchips and see if they can offer any help or suggestions to you. In the past, they were very helpful.
Good luck and safe travels!
Adding to what Doug said above, if you did not get the SuperChips unit from the previous owner, you will not be able to change anything.  And once Ford plugs in and does anything to the computer, it will probably wipe out the chip info.  The previous owner may have done that anyway since that's the only way to reuse or sell the unit.  He likely set your programming back to stock and kept the unit.
My Ford has a superchip sticker on the window, but nothing was installed. The previous owner put the sticker on first, and never did the install....
Typically a stoke 7.3 will max out at around 7 psi of boost, that's it!!  Mine when set to 350hp using a HyperTech programmer will indeed push 30psi when the outside air temp is low.

Be VERY aware that towing with the horsepower turned way up is going to cause some extreme stress on your engine.  The stock horsepower for a 7.3 automatic is 250hp and the standard transmission is 275hp. Typically you will experience a fault code indicating a fuel injector over pressure situation when towing if you put your foot into it.  Do this too many times and something is going to fail.

The other thing that concerns me is your exhaust temps.  If the probe is located after the turbo then those temps are way too high.  If the probe is located in front of the turbo you're borderline.  FYI, if the probe is located before the turbo you might want to have it moved to after the turbo.  Should the probe fail and depart it's location in front of the turbo it will exit the exhaust AFTER it goes through your turbo charger, not good.

International Harvester designed the 7.3 very well but it was not designed to produce high horse power under heavy loads.  Chips or reprogramming can indeed increase your fuel mileage significantly but trying to out-think the engineers when it comes to horsepower and load capabilities can result in a less than desired outcome.

Have your mechanic plug into the system and read any fault codes and figure out what your horsepower really is.  Let us know what they find out.
I'll have to assume you miss typed with the 7 psi of boost. So did you mean 17 or 27?

And I just picked it up from the dealer and they said it's stock.

And I'll have to get back with you on the exhaust probe location I'm at work and drove a different vehicle but I know it's high on the firewall on the drivers side, I'd have to look again to tell which side of the turbo that is (only had the truck a couple weeks). 

And everyone I know with a diesel says 1100-1200 for exhaust temp is normal while pulling 12,000 pounds wide open throttle up hill for half a mile. While cruising 65 with that load the temps were hanging around 600-700.
No misprint, 7psi on a 1999 7.3 six speed stick is about max.  Any idea what the stock horsepower on an '02 is?

I guess I've been driving Class 8 trucks for too many years but an exhaust temp ANYWHERE near 1,000 degrees on a big engine is a good reason to get your foot out of it and fast.  Even my little Cat 3126 250hp never gets above 850.  Now the Ford will pass through 1k exhaust temp if it's lugged down when loaded but only when it's lugged and I try never to put that poor little engine in that position.

One suggestion that I swear by on the 7.3 is to switch the air filter over to K&N filtration then religiously keep it maintained.  When I switched mine over I got an honest 10% increase in fuel mileage under load.  It took my mechanic months to convince me to change over and after she did I was pretty impressed with the results, your mileage may vary....

Given that your exhaust temps are running that high I would suspect that the probe is before the turbo.  There's different schools of though on this, some say that having the probe in front of the turbo provides a more accurate reading of the exhaust temperature and that the failure rate of the probes is miniscule.  I on the other hand figure that if it's gonna fail ever, it WILL fail while I'm driving it down the road so I'd just as soon have the temp probe after the turbo myself.  Modern engines are so computer controlled that the EGT is really only there any more just to give you something to stare at and take up space in the dash.

Latest posts

Forum statistics

Latest member
Top Bottom