HI FLOW MUFF or STRAIGHT PIPE

[JThacker]

I just got my 2004. 4 CTD 600 and plan on freeing up the exhaust a little. I plan to keep the cat and either replace the muffler with a hi flow one or piece of straight pipe. I would like to know if anyone has done either of these and the results concerning power, throttle response, time to turbo spool up, mpg and sound, thanks in advance.

 

[fj40dave]

Me too... . but I'm thinking of just the straight pipe (Muffler Elimination Kit my wife bought for me for my birthday today).



Inquiring minds GOTTA know!



What is the sound difference?

 

[JThacker]

Where did you get the kit and how much and how does it install, simply unbolt muff and replace with pipe?

 

[Coonrod]

I had the cat and muffler cut off of mine. and replaced with straight pipe. As far as the sound goes, it is loud. I think it sounds good. Although it does have a loud drown when low in the RPM's.



GENO'S garage sells the muffler elimination kit. I think it is around $100



The muffler shop charged me $60 for everything. Mine is welded in



Throttle responce and power seems to be up, but it could just be the sound

MPG went up about 1/2 to 1 mile per gallon-depending on how you drive



I have also just installed a AFE intake and torque tube. It gave me about and 1/2 mile per gallon better also, and the EGT's are down. And with it, you can really hear the turbo sing.

 

[ROCKJEEP]

I stright piped mine the second week I had my truck. I put a hi flow muffler on the third week i owned it. It wasn't the clasic cummins stright pipe sound. Was a raspy rice rocket sound and the drone was so bad my head hurt. got the fred swanson 4" exhaust and it is awsome. from the seat dyno it also felt like i lost power with the stright pipie. The best part with the new exhaust in free flow and no drone. EGT down also. Y might want to see a truck with a stright pipe in person first before you go all out.

Kory

 

[Yo Hoot]

Lose the muffler

 

[TFerring]

Straight pipe is the way to go... . I will tell you it has a drone at highway speed with a load, but it sounds pretty damn cool!!!

 

[Dean Upson]

I drove a six-shooter that was straight piped. It sounded great, not bad in the cab but really loud outside. I think I would get tired of the noise in a hurry. I prefer the muffled sound better overall.



Dean