First Dodge"loveit!"

I have been wanting a durango for about 5 yrs and I did just that.It's a 1999 5.9l slt plus with 70000 miles on it.One owner and It is as clean as it was when it was new!!! I will post some pics soon.Anyway I have been doing reading on preformance upgrades and cat backs,I decided to just change my muffler to start off.I talked to my local shop and I went with just removing the large beast of a muffler the factory had and put in a slightly larger dia pipe,no muffler. It is not as loud as i thought it would be,when I get in the gas hard there is no doubt im there. :naughty: As i was coming home I looked at my mpg read out and the last week it has been holding around 13 mpg 15 hwy,easy driving.Well when I looked at the read out it already moved up to 16mpg on the same 45 mph road that I take everyday.Now if you ask me that is quite a good jump in mpg.I had no idea that the stock quiet muffler would hurt my mpg so much.Nice to meet you all and I will be a regular visitor so see ya round..

I believe in straightpiping too.

Im still trying to learn and understand all this exhaust stuff. Is what you did was just remove the muffler completely and run a new pipe from the cat? Im pretty amazed that you got that much gain in the mpg from just doing that and how much better mileage you are getting then my 5.2 98 SLT which is about 10 or 11 around town being easy and about 13 on the hwy on average with you having the 5.9. If this is the mothod you chose is this better then going with say a 50 series flow with a single exit? and can you run dual pipes from a single exit? I feel kinda stupid asking these dumb questions but hey, im never going to learn anything unless I ask. Thanks.

If you're good with a welder or know someone who is, you sure can run dual pipes from a single exit. I'd never do that though. 2 pipes look cool but if there's only one exit on the muffler anyways, you might as well just have one pipe for all it's doing.

Probably the best thing to do is just run real dual exhaust. One pipe from each head, and the pipes never meet, not even in a crossover. This would mean putting on dual catalytic converters too, if you like running them. I don't.

In this case, what this guy did here is run a straight pipe instead of a muffler like a Flowmaster, and for sure it's going to be less flow restrictive since the muffler would have baffles and everything, and the straight pipe doesn't. The cat that he left on has that catalyst in it, which looks like a honeycomb, and that muffles the sound and takes away from flow a little bit.

I see, I see. Well I think I may go with just a single exit single pipe flow or something similar to one. I like the sound the 50 series puts out although im sure hearing it on flowmasters site is nothing like hearing it in person. Now you said that real true dual exhaust would require two mufflers obviously but that you would need two cats, if I liked running them, so can you actually go no cat at all? If so what affect would this have? I also heard that freeing up the air flow too much on durangos with exhaust actually affects the performance in a negative way, and that the best thing to do is get as much engine air flow via intake and throttle body spacers and such prior to exhaust to try to stop any torque loss that ive read can occur by adding exhaust that frees it up too much first. I read so much stuff in so many places so who knows if this is coming out right. Good luck understanding it, if you can. Thanks!

You don't need cats at all. Unless your state says that you need them. Maybe you have smog tests to pass? You're from California right? You better leave them on.

My idea of a perfect exhaust system is one that is dual, with no cats, but with dual glasspack mufflers like a Thrush or Cherry Bomb. A glasspack is basically just a straight pipe with some baffles in it to act as a little bit of a muffler. It's all you should need.

If I were you and living in California, I'd run real dual exhaust with dual cats, and Thrush mufflers. But that's just me.

Well here in about a month when I go to talk with the muffler man ill see what he can do for what ill have to spend. Hopefully he can set me up fairly nice for not too high of price.

Well here in about a month when I go to talk with the muffler man ill see what he can do for what ill have to spend. Hopefully he can set me up fairly nice for not too high of price.


I LOVED THE SOUND OF MY STRIGHT PIPE BUT I felt it was a bit too much after a few days so I installed a dynomax ultra ss.The sound is perfect for me.My mpg was much improved with the stright pipe and I will run a new tank this week and post next sat on my mpg with it.So I have org manifolds,cat then dynomax then tail pipe.Single exhaust is ok with me but They sell mufflers with one inlet and dual outlet if that is what your after.ALL this set me back 200 bills including the stright pipe work.I paid 120 for the muffler itself"on sale". Good luck on your syster and im off to wash my ride now :smokin:

Wow not bad for what you paid for it. I would love to have a muffler with dual exit to run dual pipes back but would I get the same affect doing that vs a single pipe?

There wouldn't be a difference. There would only be a difference if there were dual pipes down the whole exhaust path. Putting 2 at the back isn't gonna do anything detrimental or beneficial.

My truck has a single in/dual out muffler. I could have had real dual but I figured it wouldn't be worth it since it's just a V6 anyway. I just wanted the look of dual pipes, the truck can never sound good with a six anyhow.

Well then when I get exhaust put on my D im going to go possibly 50 Series Flow or something similar single in/dual out side pipes with some nice chrome tips. Sound good? And do you know what muffler type, because I dont think the 50 series does it but I dont know much about mufflers as it is, will have a nice rumble at idle and low rpms but will really liven up when I punch it? Thanks.

I recommend a single in/dual out Thrush glasspack. I'd recommend it to anyone, that's how much I believe in it. That's what I run, and I wouldn't run anything else. If you get a Flowmaster, you'll just get an annoying drone and you'll be paying for a name. Anyone will tell you that Flowmaster is "so good" and everything, but I don't see how it is. It's just a name. It just goes to show how people will still fall for advertising and everything, just because someone else has it, that's what they want. I'd never buy that crap.

Chrome tips are sweet...

Yea I hear you on that whole brand name issue lol. Ive only really heard flowmasters on trucks that I know of but when I go to talk with the guy I will find out what else he has that will sound just as good. and yea.... CHROME TIPS ARE SWEET!!!

And ill ask him about the Trush Glasspack.