Diesel EGT Question problem

[sigepmock]

Need some help here. Just installed the Banks cat back exhaust on my 05 Dmax and the EGT's went up!!???!!
Cruising on the freeway went from below 800 to right at 1000 and when I get on it I can get the EGT up to 1400 :eek: . Never saw anything over 1200 with the stock exhaust.
Here's a partial pic of the exhaust:
http://www.hotboatpics.com/pics/data/500/5495rear_shocks-med.JPG
The Banks kit looks nice, no obvious restrictions, nice clean bends, looks like it should flow better than stock.
Shouldn't the EGT's have dropped with better exhaust flow? Could the muffler be causing a restriction causing higher EGT's?
Or am I missing something.....I'm kinda new to this Oilburning thing. :confused:
I'm going to pull the muffler and run it straight and see if the egt's drop as a test. I'm just stumped so far???
Thanks,
Chris

[riverbound]

Your EGT's should go down with the exhaust. Are you running a cat or is it just a muffler.
Mine is 4" from the turbo back with a straight through muffler.

[sigepmock]

Cat back only. I've been told you can't go Turbo back on the LLY's with out using Finger stick or you'll throw codes.

[PHX ATC]

Is your cat plugged?
Is your muffler on the right direction? Sounds like I'm slamming you, but I'm not...I almost put mine on backwards...there is a directional flow on some of them, so you might check.
EGT gauge grounded properly? It sounds like it's okay, but might warrant a check.
Do you have a chip on your Duramax? If so, what setting? It might be sending too much fuel, thereby too much power (temp goes up) that the stock exhaust in front of the cat can handle. In other words, the most restrictive portion of you exhaust (head to cat) might not let it flow as much as it should with your other mods (if any). Do you have an aftermarket air filter? If not, maybe that would be your next upgrade.

[djunkie]

Have you changed anything with the ECM? Be very careful. If your pyro is reading correctly you can melt your turbo by getting it that hot.

[sigepmock]

1500 miles on the truck, mufflers on the correct way "Inlet" in, "Outlet" out. I have the Predator programmer set at 65hp. K&N drop in filter only.
Funny thing is with everything the exact same except with stock exhaust. I saw the lower numbers. Changed the exhaust and BLAMO high EGT's. I just can't figure out how this muffler could be worse than stock.
Well looks like I'm gonna pull it and see what happens.
Thanks,
Chris

[PHX ATC]

Granted, I have Dodge Cummins, but my 01 is straight piped and saw no change in the EGT's (it is 3.5" piping). My wife's 04 I put the MBRP and saw a 200 degree reduction. It has from the downpipe back, with muffie and huge tip. Essentially they are the same engine, except her's has a better fuel management system and is quieter.
Maybe the muffie was mislabeled as to the inlet/outlet? Did you mess with any of the stock sensors when you put the exhaust in? Accidentally bumped them? Any sensors in the cat?
If the EGT gauge is electronic, try undoing both the batteries for 30 minutes or so, then rehooking them back up and see if the gauge shows any different readings. Maybe unhook the Predator and run it that way and get a reading and see what it compares to with it hooked up.
Where is your EGT probe located: in the manifold, the downpipe, or regular exhaust piping, before turbo, after turbo? You didn't change the location of that did you? I'm sure you didn't, but maybe you did as before turbo they will read 200 degrees or so hotter than after turbo and give you a better reading as to what is going on in the engine (before turbo location).
Trying to help as I know it sucks when something is amiss.
Toby

[sigepmock]

Problem Solved!!!!!. Damn tuner was the problem. Didn't notice it before the lift. The added load of the 35's and the programmer sent the egt through the roof. Removed muffler completely and still high EGT's, returned the tuning to stock 1200 max and lower through out RPM range. Spent an hour on the phone with Diablo Sport, they have a revised program for the newer DMax LLY's to fix the problem but it won't be out till next month....maybe.
Diablo Sport Predator is in the box on the way back for a full refund. Edge is on order. I should have listened. :hammerhea :hammerhea Sorry Keith and Jordy.
Chris

[PHX ATC]

Glad it's fixed.
I've Edge products on both of our diesels. You can't go wrong.