NDanecker

Someone PM'd me about this exhaust and I responded. After writing this I thought it would make a good post for everyone so....
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The standard kit replaces from the cat back, but you can get a cat replacement pipe like I did for an extra fee. MBRP said the downpipe is already 4" and looks clean. No need to replace it as they'd probably just duplicate it anyway.

Installation is pretty easy. Just don't try to 'slip' off the existing exhaust. It won't work. The stock clamps crush the pipe so much that slipping off the cat/muffler is near to impossible. I cut mine.

Drone......I really don't have any and I tested it through the entire band. I had a straight piped 2003 VW Jetta TDI that was so bad I got headaches! The cummins is different. I think the dual exhaust helps the drone......IMO. I cruise around 75 and its very quiet with the windows up, but you can hear a slight rumble. You can just hear sound of the diesel motor over the exhaust. Haven't towed with it yet though. Like I said if you take it easy its ok. But once you have the throttle past halfway or floored it gets very loud! I'd almost compare it to a open piped Harley! Forget it if some poor slob is next to you and you jam the throttle. Its gotta hurt their ear drums. The good part is you have some control over the sound. Seems like throttle position has more impact then RPM's. Around the neighborhood I take it easy and its fine. But open it near a building or wall with the windows down watch out!

I get many looks when driving down the street from guys...women don't pay attention. It's a different sound....not a rice rocket....not a hemi.....not a mustand with flowmasters......people just hear something that sounds cool that they probably never heard before!

As for HP/Torque.....seat of pants tells me I've lost some low RPM torque. You can feel it. But once you get the RPM's up high around 2k you feel it come on. Better then stock. Feels like the motor wants to rev as before it felt restricted with the stock cat and muffler. Cruising above 80 mph seems easier...less throttle required. Still have no problem turning 315's with 3.73's, hills, etc.

Highway MPG seems to have gone up slightly. City seemed to drop. Might because I rev it a little higher around town to hear the exhaust now. :-)

Hope this helps!!

chuckmcdonald

I added the Silverline version to mine. At first I did not have a drone. Then I got it on the highway. At 75-80 it would run you out of the cab. I added a Magnaflow 20 inch muffler to it and all problems solved. I did not have and loss of power/torque that I could tell and my MPG went up about .5 to .75 according to the overhead. I have not towed with it yet so I dont know how it will sound.

Mark Craig

NJTackle,

We have sent out a lot of the 600 systems and especially if you leave the cat in place the drone is not there. With the cat out you hear it a little. We also have a new resonater that is very effective at killing drone too, in fact some of the folks that have used it sort of complained that it quieted the system too much!

Mark @ DPPI

NDanecker

Hello Mark,

I guess it's hard to say if its drone or just a loud exhaust. Personally I can't hear any drone but that is just me. Everyone's perception can be different here. Either way, it doesn't bother me and I'm happy.

My significant other drove in the truck 4 times with the windows up and didn't notice the difference in exhaust tone, even though it is slightly louder. It was only until I drove with the windows down that she noticed I did something with the exhaust. She said it sounds like 'your truck is louder'! I said, "You mean like a rice burner?". "No!", she said. "Just like its blowing a lot of air, and if it wakes the baby in the morning I'm going to kill you!" I changed the topic and made a note to self: Never ask wife for opinion on BOMBS!

If I had to buy an exhaust again I'd go with the same setup! Very Happy!

NJT


Edited by Admin

amartinson

Good Policy!

Mine is starting to wonder why things keep "falling off".

Exhaust "fell off"

Air Filter "fell off"

A-Pillar cover "fell off"

I need some new excuses.

Stingerpup

Are there two types of 600 systems available for purchase?? Or is there a 600 system that leaves the cat in place, and others are using the 555 system and removing the cat??

BallisticDiesel

I have the Ca So what is the Dual system like for mine? Does it use the stock Cat or do I remove it and put a whole new system on? My exhaust right now goes out 4 inches from the turbo. Does it matter if you leave the cat on? I am a newbie and I want duals. I want it loud but not to the point where I can't stand it. Though I wanna wake the neighbers up @ 0530 when I leave.

Don

wexman

NJ, nice write up. I am a little concerned about the perceived low-end torque loss. You really think you lost some?

BallisticDiesel

Whats the difference in the T-304 and the T-409 SS? Other than the huge price difference and the tips being included?

Donnie

NDanecker

Hello Scott! How's the dually running?

Yea, I believe I've lost some low end grunt. I had a dyno done way back when at XTreme Diesel in Wall when the truck was totally stock. I'll eventually get another dyno done and compare curves. My butt-dyno says there is a drop on low rpm grunt. Runs much better once turbo is spinning and rpm's are high (>1800). I've got the 6-shooter so I've got no plans on racing anyone. I'm happy with just motoring down the highway listening to diesel engine and exhaust, getting great mileage, and living life!

I wonder if MBRP/DPPI has any dyno info??????? Mark????

EDIT: I understand that less exhaust back pressure causes the turbo to take longer to spool up (pressure differential). This may be the loss I'm feeling....more turbo lag. Just one concept. Dyno will tell!!!

Mark Craig

NJTackle,

I am with you on that one, I can't hear a drone on the ones we have installed either, I think it's more often than not just the bang of those 6 cylinders hitting that you can finally hear a little of when before you couldn;t hear anything at all.

Mark @ DPPI

Mark Craig

Stingerpup,

The 600 systems are different. They do not include the down pipe, the factory one is pretty darn good unfortunately for us but good for you the consumers ! The systems connect at the cat exit, use our 4 inch mandrel tube and Spiral Flow muffler etc. The duals work the same way. We do have a cat test pipe for those that use their truck for racing and off road use too.

Mark @ DPPI

Mark Craig

BallisticDiesel,

Get the dual system as we have it ready to go and see what you think of the sound and volume, everybody is different so you need to see what you like etc. If you want the cat test pipe is an option for you. 409 is a good, better than stock material that comes on most of the trucks today. It will grey/brown ouit and in tougher climates get some spots on it. 304 is the best of the best as it has a lot of chromium and nickel in it that makes it pretty much impervious to most anything that is thrown at it from the DOT's out there in the winter. It is extremely hard to bend and has a lot more spring back than 409 and becaue of that there is a lot of scrap when bending it. Between the cost of chromuim and nickel and the scrap rate thats the difference in cost.


Mark @ DPPI

Mark Craig

NJTacklem,

No none that addresses torque loss anyway. What you are probably feeling is actually sound differences not torque differences. The sound that you hear makes your mind think the torque has changed, but in reality it hasn't. It happens to me all the time in the race car when you change engines and or cams, even rear gear ratios etc.

Mark @ DPPI

wexman

Running like a top. 5000 miles so far, and I'm still all grins. I'm just trying to decide on exhaust systems, hence my interest in this thread, and your experience.