Just curious, DIY - do you still have the factory Dual Mass Flywheel? i would suspect a wide-open exhaust system would prevent the engine from slowing itself down as quickly when compared to a more restrictive system (like you're seeing), but that such and effect would be more pronounced with the DMF, and maybe less so with a Single Mass replacement.

i ask as i'll be doing a trans swap soon and plan to install a 3" downpipe at the time. i was planning on an all new 4" straight pipe (no cat, no muffler) exhaust system as well, but now you've got me thinking if really want to do that. maybe i'll put a muffler in the setup, or just go straight 3.5 pipe (no cat).

 

My truck is an auto.

My $.02 is that the straight pipe sounds good but it is a little loud for my taste as a daily driver goes. The truck is loud enough inside the cab anyway, but with a side exit exhaust right behind the cab like mine was, it was LOUD when I would get on it. Towing the camper in the summer time.... better have A/C cause if you run with the windows down you have to shout to carry on a conversation. I like the turbo whine, but the drone I could do without. I think a small straight through muffler would allow for a nice balance of both.

 

that's pretty much what i was thinking - straight through muffler. My current plan is: the 3" DP, into a section of 3.5" straight pipe, then 4" into and out of the muffler, then out the passenger side in front of the rear wheel. still need to do the geometry, but it should work - basically swapping my cat for a straight through muffler.

right now, i've got the stock crush tube DP, into the stock 3.5" pipe, into the factory cat, into 3.5" straight pipe with a 60 degree bend out the side in front of the rear tire (no muffler).

Its definitely loud (but passed inspection in PA, to my surprise). I don't mind the noise too much, except that i can barely talk on the phone in the truck at all, even with the windows up. ...and as i'll be going from auto to manual, its only going to louder.

 

I wouldnt go 3.5. Go at least 4''. You can make the straight pipe a little quieter by running it all the way out the back instead of doing a side dump.

 

I just put a Diamond Eye 3" down pipe in my truck. I couldn't get it to line up with the cat to save my life so I left it unattached to the stock system. Like you said Nate the turbo whistle is awesome but the drone is ridiculous.

Red

 

Huh? What'd y'all say? Sorry my awesome straight pipe isn't allowing me to fully hear y'all.

 

 

I can't hear any of y'all either. I got a straight pipe and a 6" smoke stack about 2 1/2 feet from my head. LOL

 

Nate, I have the Diamond Eye 4in exhaust with the SS muffler and a 5in tip. I have been meaning to get a video and post it here for you, just been busy. I should be able to get it this weekend.

 

That would be great Chris. I think I would really like that kind of setup.

 

that's the exact system i'm considering - though i assume yours come out the back (behind the wheel) rather than out the side? i think i'll stick with out-the-side as i have grown to like the look and its an easier (and cheaper) set-up to build for the DIY-er.

is your muffler a striaght-through style?

 

I put a Diamond Eye 4" w/ their muffler on a friend of mines extended cab OBS a few months ago. Their muffler is a straight through style, but it was too quiet with the muffler, so we straight piped it that same night. The 5" would make it a little deeper, and drone might be a bit worse. That 4" straight pipe out the back doesn't drone much, if it does at all. Really quiet in the cab, especially compared to having the freaking cannon right beside my head.

 

i got a 5 inch diamond eye with a 6 inch mbrp tip the drone aint bad but the turbo whistle is awsome

 

I've got the Diamond Eve 4" turbo-back system with the 3" DP, cat delete ("off road" as they call it) and flow-through muffler. It runs exactly where the stock system ran, and comes out in the stock location , though I was able to angle it a little and put a "slash cut" on the end of the pipe - I think it looks better that way.

Here's the thing though - I've had this exact system on two trucks now (I mean the EXACT system, I switched it over from my ECLB to my CC), and it sounds different on my CC than it sounded on my EC. In my EC, you could hear the turbo whistle a lot more prominently than you can hear it in my CC. The only thing different is about 1 foot of extra pipe on the CC than the EC. I don't think that would make that big of a difference, so it's got to be the difference in the two engines, though they are the same engine. The EC ran a lot smoother and had 100K less miles. Maybe that was the difference. You can still hear the whistle on the CC though, and there is not much drone. This is a perfect system for me. I am not incredibly fond of Bill's 4" straight pipe - it is too loud for me. I like the way this system sounds, though I liked the way it sounded on my EC better than it now sounds on my CC.

I have been meaning to get a video posted up for several months now. Sorry Nate! It's been in the back of my head all the time...I just haven't gotten to it. I'll try to get it up here soon so you guys can hear it, though there's not really much to hear. Overall, I've been happy with the system, though I am curious to see what it sounds like without the muffler. Maybe I'll unhook it one day and see.

 

I dont like the whole exhaust out in front of the rear tire. It gets soot all over the back side of your truck/bumper.

But thats just me! lol for an extra 2' of pipe ill shove mine out the rear!