I finally bit the bullet and had a 4" system installed today. After last month's trip with the camper on the truck and towing the Jeep on a trailer, I desperately needed to bring the EGTs down.

I won't know how much I accomplished temperature-wise, but it looks like I picked up 2-4 PSI (traffic was too bad to really "play"). The only thing I regret is having the big Dynomax muffler installed...it's too quiet. Oh well, guess I'll swap in a glasspack or something similar somewhere down the road - I really miss the nice sound the 3" glasspack gave me.

Any other tips on bringing the EGTs down? I'm sure the exhaust will help, but I also know more will have to be done to use the available power - it really sucks being limited to 1/3 pedal because the pyro is sitting at 1200*.

 

geesh, what MILD pump tweaks do you have? with no load and all my mods below i hit 1200 floord getting on the highway with no smoke and about 24psi

 

One turn in on the power screw, 90* on the diaphram, 1/4 turn CW on the starwheel...and one turn CCW on the smoke screw so I don't fog the neighbors too bad.

Unloaded I don't see 1200* at all. It was when I was pulling heavy up some long, fairly steep hills that I had problems with EGTs.

 

oh that makes sence then, ill get some good reading this weekened as i am towing up hwy 80 to do some 4x4jiMMy

 

What muffler did you use?

 

The big Dynomax - it's almost the same size as the stock muffler. The guy at the shop is running one on his '01 Dodge CTD and said it had a nice tone. Either the 24-valve engines are louder, or his taste is greatly different than mine.

Oh, well...the neighbors will probably appreciate the new system more, since they won't hear it as much when I get home from work around midnight. I'll give 'em a few months of peace and quiet before I change anything (unless the idiots don't keep their $#!$!@#$! dog quiet...then I may just straight-pipe it).

Jimmy - Let me know what you see for temps, and what kind of weight you're pulling.

When just pulling the Jeep on the trailer (~12k pounds total), or just have the camper on the truck (~7700 lbs total), I haven't had any problems. It's was just when I had the camper on and pulling the Jeep on the trailer (~14k pounds) that it was an issue, and then only on the longer/steeper climbs. On one section (7 to 8% uphill grade, ~ 7 miles long with little or no break) I was in 2nd gear, 25-30 MPH, using very little throttle because the EGTs would skyrocket with any more fuel. I had a lot of really happy people behind me - no place to pull off, and passing zones were few and far between.

 

I have a Dynomax muffler on my truck and I love it, some times I wish it was a little more quiet.
I got it from JEGs, $73.99 part number 289-17225, 4" in and 4" out.
I would guess that you need to go to a 16 CM housing on your turbo or go to a better turbo. This would keep your EGTs down.
I can pull 14K GVW at 70 MPH at 4600 elevation, for a long time, I just have to worry more about coolant temp than Pyro temp.

 

Muffler????? JOO_DON_EEED_NO_STEEEKEEN_MUFFLER!!! Hey really, i got rid of mine when i went to the 4" exhaust. My turbo is the muffler and there's no sweeter sound. Not as loud as i thought it would be either. More turbo whoosh than harley whoosh. Absolutely beautiful, especially at night when theres no other cars around, or at the airport parking garage.And i live in Tampa congested area, neighbors dont mind it either (Or they're fraid to speek of it)
-Jim-

 

Jim
I agree, I currently dont run a muffler.
But I love my truck, I love my wife. I love to drive my truck. I love my wife. The only thing louder than my truck- my wife, and she wont go any where with me in my truck. so muffle her it is. (the truck -not my wife)

 

I ran mine straight piped at first but it was a little too loud for my neighbors... MY magnaflow was too quiet for about a week then it broke in and was almost as loud as straight... just took the edge off a little but still sounds great. In fact people still comment that my truck is loud. lol

 

I love my wife too, but if she says muffle it, i will. Bout 2" of duct tape should do the job.
-Jim-

 

I'm running a 16cm housing - guess I need to put that in the sig.... A turbo would probably make a big difference, but the $$$ just isn't there right now...gotta buy tires and wheels for the truck first, and I ripped a tire on the Jeep last weekend so I need a new set for it, too...at $170 each.

Hopefully the Dynomax will "break in" and give a nice tone after a few weeks.

 

If you want a high flow glasspack, try one of these.

Pretty cheap from Summit Racing.

 

I actually had a choice between that and the muffler I went with, but was concerned the bullet muffler would be too loud based on the comments of the shop owner.

There is a 2nd Gen in my neighborhood that sounds great. Guess I should have taken a better look or talked to the guy before having my system installed....