as a few of you know, I bought a third powerstroke a few months back. It runs good, but I have noticed high EGTS when pulling 15 to 20k. At 60 mph in OD with my 97 Dually, I run about 950 to 1000 degrees pulling my 15k 5th wheel. In my 95 Dually, I see 1100 to 1200 degrees at the same speeds. Both are autos, same rear end, tow tunes with same programmer, same intake and a 6637, etc.... so I started snooping under the truck.

Someone had removed the flat downpipe in favor of a std 3 inch, but its 3 inch all the way back to the axle, then goes to 3.5, I always thought bigger was better, so I found this exhaust system on fleabay, and thought it was a decent deal since it had free shipping, I thought maybe it could evacuate the gases a little quicker and lower the egts. For 300 bucks, I dont think I can go wrong, but what do I know....LOL

eBay Motors: 94 95 96 97 98 FORD POWERSTOKE 7.3 4" EXHAUST (item 320240571240 end time Aug-13-08 18:50:47 PDT)

 

Turns out that it was a wrong listing...............................Oh well..........

 

I called the guys anyhow to see what they had. I can get the 4 inch catback aluminized for about 265 including shipping. He wanted to know about an intake, which got me thinking about the 6637 filter mod. As we all know, cold air is what builds HP right? So since there is no way to keep the residule heat out of the mtor compartment with some sort of a box with a inlet pipe to scoop in the air, are we still sucking in 140 plus degree temps? I wonder what happens if you could use a airbox with a inlet pipe to get some fresh air in. I am very curious now to get one of those temp sensors that you can mount in your car to monitor the engine compartments ambient tep while driving the speed limit. If it is significantly higher than the ambient outside temp, then I think I may start building a 6637 fresh air kit................

For those of you tired of reading all my posts that are consecutive, I am sorry, but it helps when I debate with myself.

After all, I am schizophrenic, and so am i.

 

Not sure because I had to send it back to be reprogrammed but the Aeroforce Gauge I beleive can monitor intake temp from the sensor at the filter. Plus its just and awsome freakin gauge!! And for the price you can't beat what it can monitor-plus the injector buzz test and cylinder contribution.

 

I have been watching intake air temps (temp at the inner fender where the sensor lays) and at highway speeds for sure the under hood temps are ambient. I have not watched it much in city driving. I will watch it more.

 

How much difference in EGT should I see if going from a 3 nch system all the way back to a 4 inch catback system? Any? From a simple dynamics aspect of it, I can not believe it would be that much since the only thing holding it back would be turbulence friction. Am I wrong on thinking that?????

 

Maybe 50-100 degrees if you already have a down pipe depending on how good the bends are in the system that is on there now

 

TJ your new avatar is pretty sweet.
Sorry
I've heard advertisements for whole systems making as much as a 200* difference, but not sure on how honest that is.

 

I saw a 50 degree drop going from the stack setup my truck had on it (3 inch dp, striaght pipe not cat, hacked up stock exhaust up to a 3 inch square tube in the bed with one 3 inch inlet and two 3 inch outlets into 6 inch stacks. It was one of the worst flowing setups I think you could have. That was changed out for 5 inch after the down pipe with 2 90 degree bends for my side pipe.

The biggest drop in temps will be going from a stock DP to a 3 inch DP

 

I guess a intercooler is now going in..........How much of a difference will that make in a towing application??? My goal is to see a 200 degree decrease during a heavy tow, flat ground. Is this a far fetched dream??? Perhaps I better check to see if the truck has a aftermarket chip in it as well. That might be helpful.............LOL