Ford 7.3 Powerstroke Diesel

[RALFF]

I have a 99 Ford F-350 dually with 7.3 diesel and I just bought a used performance chip for the engine computer. The truck now runs the best it has since I bought it last year but a friend has told me that when I pull my gooseneck trailer with a load on it I may run into a problem with the exhaust gas temperature getting too high and damaging the engine. He says that I need to upgrade to a 4 inch exhaust system. Is this a legitimate concern?

Thanks, joe

[Rocky_J]

Which chip? Is your exhaust system stock?

I know several guys with Ford diesels and all of them have upgraded to aftermarket or custom exhaust systems. Cooler temps and better fuel economy. I know two guys getting 17-18mpg around town, 12-13 pulling heavy equipment. I'd recommend the exhaust system with or without the chip.

[IMERC]

anything ya ever wanted to know and then some....

www.thedieselstop.com/forums

[rebocardo]

> Is this a legitimate concern?

Yes, but, a gauge would solve most of the concerns or worries or tell you if you really needed a  new exhaust.

Go to summitracing.com and search for

"pyrometer"

If you have an automatic I would add a temp. gauge for the transmission and upgrade it to a separate fan cooled radiator before I worried about the exhaust.

[Dave Shepard]

The powerstroke really likes to have a better exhaust. The down pipe that goes between the engine and firewall on some years is squished almost flat. I know several people that have changed out just the downpipe with noticable improvement. The only downside of the aftermarket exhaust is it makes them sound like a 9.0 liter IH school bus. :


Dave

[Dale Hatfield]

The chip you added depending on the make. Adds more fuel and changes timing. which can help and hurt when towing. not nowing the setting or the chip make. I cant say how bad it will affect towing.
Check out the makers web  site and see what all the chip does for your truck.How much HP is added by adding more fuel as well as boost will increase so does EGT.
I can tell you that with an automatic that towing heavy loads , higher than stock power is hard on tranny. Keeping the auto locked out of overdrive will help EGT.
If its just a small chip its prolly only about 60 hp added which is mild but a guage would be nice to watch. I would buy a dual guage EGT and Boost 2 needles on one guage is about 200 bucks.I would have a diesel shop install the guage as ya have to drill the manifold  which could put small drill chips into turbo if done wrong.
When adding power its nice to add more air in and out . So new filter system and bigger exhaust  is whats in order. I got by with a stock exhaust for long time - the muffler.
I have 2 built cummins rams and the stronger of the 2 will tow whatever i pile behind it with plenty of power left however the EGT wont allow for full power towing = full meltdown but it is an extreme case of added power.

[Dave Shepard]

Dale, you'll just have to bite the bullet and get a set of twins. ;) I can tow up to about 350HP/900ft/lbs without going over 1300 on the pyro, any more and it'll bury the needle at over 1500.


Dave

[TexasTimbers]

Joe, I run a 99 F350 7.3 powerstroke as well. I installed a chip too. I am not an expert just giving you my experience with them. I forget the brand it was one of the more expensive ones. I have the box and the handheld readout thingy that comes with it.

It has 3 levels of HP boost to it. Going on memory here but this is close. It offers 65HP, 95HP, or 125HP extra. My mechanic friend told never to set it above the 65HP setting since I tow with it. He also said he didn't think I needed to upgrade my pipes at that level, but after towing heavy loads not to ever just shut the engine off after a hard tow, but to let it idle for about 5 minutes so the turbo blower could cool it down.

I'm somewhere over 280,000 miles and  have never had a problem so I guess he was right. I rarely shut the engine off right away like he said, so I want to assume I have maybe avoided a problem that way. It's best to have gauges for sure. Takes the guesswork out.

I can't imagine how wicked the thing would run at the 125HP setting. Just the 65 is freaky. I mean a truck that heavy and that long (mine is the longbed crewcab) should not run that fast! In fact, IMO if I ran the 125 setting even not towing I think it might be too much to ask of some of the parts on that truck like the transimission, the turbo, the u-joints etc.

[Dave Shepard]

I recommend a boost and pyro gauge to anyone running a diesel engine. They aren't really needed on a stock truck, but can be a very handy diagnostic tool for stockers and tuners alike. I ran a K&N oilable filter in my Dodge, and it sucked all the oil out ruining the MAP¹ sensor. I'll be putting a BHAF² soon. Being able to monitor boost and temp are very important when you are nearing the safe limits of towing. The reason you need to idle any turbo charged diesel is to lower the EGT³ to prevent the oil from cooking in the turbo. On my Cummins, the EGT pre-turbo needs to be under about 350°F. Having a gauge saves on guessing. Max towing EGT is 1300°F. My chip adds 225 HP and the injectors another 40 HP, I can't use all of it towing, or it will cook the engine in short order.


Dave


¹Manifold Air Pressure
²Big Honking Air Filter
³Exhaust Gas Temperature

[SwingOak]

A lot of the chip makers recommend installing an exhaust temperature gauge with any change made to the programming, or fuel system on the truck. A bigger exhaust will help the engine breathe better, and will almost certainly boost performance.

This guy seems to know what he's talking about: http://www.kennedydiesel.com/