My father and I both have the same truck...Well, his is a 2007 sport...mine is a 2007 Laramie. We both installed a Magnaflow Catback..mine is dual out the back. His exhaust is single out the side. I have a AFE CAI...he has a K&N. Only difference in the cold air intake is his goes directly to the throttle body...mine only goes to the resonator. (AFE IS CURRENTLY WORKING ON A EXTENSION TO GET RID OF THE RESONATOR). Only difference is my Dads truck is Superchipped.

Why is his truck SO much louder? He has about 10,000 more km than me on his exhaust. Could it be I havent burnt out my glaspacks yet?

I have notices that I have 2 Catalytic converters..My stock header pipes come out...stay into 2...run into a Cat on each side...then a Y pipe to my muffler and back into dual out the back. From what my Father says...he only has one cat...his stock head manifold connects into one Cat...straight to his muffler and out the side...single exhaust. His truck is WAY louder than mine...idling is louder...on the throttle is way louder.

What can I do to change this?
Are the two catalytic converts only there to muffle the sound because its the "Laramie" and his is "Sport"?

Is it cuz my CAI goes only to my resonator?
Will getting the extension to the throttle body, available soon they say, make it louder?

We're in a little competition and I want my truck louder than his. I will soon be installing headers..I have heard Longtube headers are louder and give more power...is this true? Or are the shortys better?
Also...Hi-flow cats...wil this make a difference? I have also heard the stock cats on the dodges are already hi-flow...is this true?

Fill me in PLZ!!!! I want my truck to be loud...and especially...louder than the old mans!!! muahahaha! lol. Any info will be appreciated guys.

 

his is single out the side and yours is dual out the back? you've got way more pipe and therefore much more space for soundwaves to lose energy, his is louder because he's not losing as much sound energy to the pipe

 

Didnt I just post explaining this a couple of days ago?

 

uh oh..............

true that shorty pipes are louder though

 

The pipes are part of it but the AFE with the resonator is much quieter than without it (I have the same setup and fabbed a pipe to remove the resonator out of an MIT tube and it is quite a bit louder).

 

He is definatly getting more intake noise then you, the resonator "Hemi Hat" is there to do just that, quiet the intake..
I found the superchips on 91 tune made my engine sound more refined and quiet ,,

 

LOL.. Hammer DID explain this a few days ago. Im not going to be a Dick and mention the search on you, but...

Basically what was mentioned was even though you might have a straight pipe exhaust, if it is extended all the way to the rear of the truck, the sound will still bounce around in the tubing, and dampen the noise. You could take your truck, idle it, take a Db reading; then take the exhaust cut it off, and kick it out the side, and your second reading would be louder. All because there is less matyerial to soak up the noise.

Kind of like the walls in a motel. The MORE wall, less sound you hear through them. SO... The MORE exhaust pipe you have, the less you will hear through them...

 

True as well, the Hemi Hat makes the exhaust quieter. I went back to the stock airbox and hat setup from a CAI and the exhaust did quiet down a bit.

 

Hey guys...sorry about posting before searching. I didnt think of it, at all. My exhaust is only a cat back...same as his. But unlike his, mine has 2 CAT converters...out from my headpipes..they stay into 2, go into a cat on each side of the truck, then a crazy Y pipe and into my muffler than back into 2. My dads goes from his headpipe...the headpipe manifold meets connects all 8 cylinders into the one the one cat, then muffler then out the side. AFE is making a peice to get rid of the resonator combined with a throttle body spacer...i will be jumping on that asap.

Im thinking of getting shorty headers, hopefully without having to get different heads because im unsure if they are alumninum.

Are the cats HI-FLOW on the stock 2007? If not i will also be purchasing 2 hi-flow cats.

Now...sorry if im bugging you guys with the questions...but im looking for answers on specific subjects. I have a cat-back dual out the back therefore if I wanted to go true dual exhaust I bassicly spent 1000$ for nothing on my catback...If I get a high performance Y PIPE...will this also help?

Im going to look into a way to keep the exhaust on, maybe cutting one of the pipes and making it true dual without tottaly scrapping the exhaust...I have heard going true dual will not give me enough back pressure and i will actually lose power..unless i get certain modifications....is this true or will true dual give me more power?

 

Again, these are commonly asked questions and there are probably a dozen threads on this in just the last couple of months. So if you want to really soak up some ideas, do a search.

Now I am not really a big fan of a "true dual" setup, especially in a heavy truck. IMO you need someplace to balance the exhaust, this could be at a "Y", "X" or "H" setup. Yes, the stock "Y" is restrictive as hell and so is the Hemi Hat.

I redid the entire exhaust with long tube headers, cut out the cats and felt I lost some low end torque. Might just be my miscalibrated butt dyno, but I felt STRONG mid and high rpm gains, but felt I lost a little down low. Put the cats back on and felt that the low end was at least as good as stock.

The stock cats are not classified as "high flow", but the concept of the Hemi heads is all about breathing and I'm told the stock cats are among the best flowing stockers on the market today. Lot of technology available for such, these are not your father's 1970s era cats...