True Dual exhaust

MARYLAND SMIB · #1 (**permalink**) 09-20-2005, 09:04 AM

I looked through the forums and I didn't see anything posted specifically on this.
I have posted a question on cats some time ago. So my question here is has anyone done this? And how have you liked it? And is it loud?

I want to run a Magnaflow muff P/N 11386/12586/12468 not sure which one, hopefully the quietest one. I want to run 2.5 inch pipe out the back no tips just very conservative.
Also has anyone witnessed any better fuel mileage from doing this. Also for smog test, and from my first hand experience Maryland just plugs a small box into the under dash outlet and then down loads any codes?
any positive results would be appreciated.
Thanks

BrianA · #2 (**permalink**) 09-20-2005, 09:50 AM

Not sure about the specific set-up you are asking about?

Are you talking OEM pipe to a single-in/dual-out muffler?
If so, lots of folks have done that. I did it on my 2000 and my 2005.
As far as volume, it all depends on the muffler. My 2000 had a MelloTone and it was fairly quiet but loud enough to have a little "rumble" - it was clear from listening it wasn't factory exhaust.
My 2005 has a Flowmaster and it is a LOT louder than my 2000 was. Really almost too loud fro my likes.
I didn't notice any change in gas mileage on either.

Now, if you are asking about fabing a new system from the cats all the way back to a dual-in / dual-out muffler, I can't help you any.

Honestly, I wouldn't spend the money on that even if I had it to spend. I don't expect you'd see any increase in performance, and you MIGHT see a decrease.

Exhaust gas flow is a science, but (IMHO) I believe you can screw up by letting the exhaust gas flow TOO freely. It is NOT - based on lots of reading on my part - a matter of backpressure. It IS a matter of exhaust gas velocity. If you get the pipes too big the exhaust gas velocity drops and it starts to effect things like scavenging and pulses.

I'd suggest a SI/DO muffler and pipes out the back.
FWIW, I smashed the chrome tips on the 2000 model hauling a dozen kids through the woods going to play paintball. I took the Sawzall to the tips and likeed the clean look of no visible exhaust pipes (they stopped just before the bumper).

best of luck and let us know what you decide.

4.2manster · #3 (**permalink**) 09-20-2005, 11:14 PM

hmmm.....

theres quite a few people running true duals, and you could see a decrease in low-end power. Nay, you will.

I have stock exhaust, with a flowmaster 2.5" 40, and MAC headers. After installing the headers i have virtually no bottom end.

I plan on switching to a 3" muffler, and maybe hi-flow cats, at that point my bottom end will be non-existant.

Use the search button, you'll find a bunch of stuff. There was a guy here by the name of Sigma, and he had true duals. He seemed to like it very much, and by no means is he naive. He knows his *****, and he's got a L!!!

MARYLAND SMIB · #4 (**permalink**) 09-21-2005, 08:00 AM

Well good posts I just wanted to fish around, I think what I'm going to do is work off my excisting pipe from the muffler back and just go bigger(3") and re hang it. And not spend a bunch of money on it. I'll keep my options open. Thanks all!

4.2manster · #5 (**permalink**) 09-21-2005, 03:54 PM

if you are going to do that i strongly suggets getting a flowmaster y-pipe, or merge pipe.

it takes the 2.5" pipes from the cats and combines them into a 3" outlet, so you can get a 3" muffler.

The stock y-pipe sucks, it's 2.5" in and 2.5" out. That means 2 pipes, of 2.5" diameter, basically get crammed into 1 pipe, and is VERY restrictive

MARYLAND SMIB · #6 (**permalink**) 09-22-2005, 09:23 AM

Thanks I'll highly consider that move. Sounds about the best. When I do this I'll post how it came out. Might a few before I do it.

4.2manster · #7 (**permalink**) 09-22-2005, 10:12 AM

i've had the aforementioned y-pipe for a few months now, i think the last place i put it was under my bed.....

haven't gotten around to ordering up the 3" muffler.....i'm just too lazy

MARYLAND SMIB · #8 (**permalink**) 09-26-2005, 07:38 AM

Quote:

Originally Posted by 4.2manster

i've had the aforementioned y-pipe for a few months now, i think the last place i put it was under my bed.....

haven't gotten around to ordering up the 3" muffler.....i'm just too lazy

Actually I'm all for doing it today, but just being able to truly justify the cost with the wife? I'll check into it and I hope it will be a good fix and decent sound.

MARYLAND SMIB · #9 (**permalink**) 10-05-2005, 08:04 AM

Well on Friday I'm going down to get my truck re-done, this time using 3" pipe and a 50 series Flowmaster with a low profile exit, no shiney tips! I just want a sturdy system and something that is going to be respectible? Well I hope it will be all I wanted??? Keep you all posted.

MARYLAND SMIB · #10 (**permalink**) 10-11-2005, 08:01 AM

Quote:

Originally Posted by MARYLAND SMIB

Well on Friday I'm going down to get my truck re-done, this time using 3" pipe and a 50 series Flowmaster with a low profile exit, no shiney tips! I just want a sturdy system and something that is going to be respectible? Well I hope it will be all I wanted??? Keep you all posted.

Well I did it, I am using the 3" pipe now with a 50 series F/master and it is a lot louder, but deeper, and it feels much freer. The cost well I should be shot for that, but I've done it and one more thing finally done. But I noticed a difference right away although I haven't offically cracked down on it, but I fee the difference, less restiction, less petal use than before. Hope that is a good thing!