Performance Muffler Question

[Walkercraig01]

Ah didn't know that

 

[DPGDirk]

Sounds like the magnaflow Y-pipe and that Jones muffler that Jough is using would open things up a bit. I'm getting a bit older and quiet is OK with me.

I'm wondering if there's any other reasonably priced mods I could combine with that (along with a BB tune) to make around 50HP or if I'm gonna be looking at camshaft, intake swap, etc...?

Just want to pep up my daily driver a bit but keep it reliable and economical if I keep my foot out of it.

Any help is appreciated! I haven't done anything to increase performance since the carburetor days, so I'm way out of my element here!

Thanks!

 

[JennaBear]

Cam and LTs would be good.

Sent from my fone.

 

[jough]

My freeway cruising mpg (67mph with cruise control on) took a 1.0 to 1.5 mpg decline right after the new muffler install.
Today, after about 300 miles on the new muffler, mpg is still down about 1 mpg. in town is same or slightly better. I am expecting a 1-2 mpg increase at freeway cruising speed with the freer flowing muffler. Are my expectations unreasonable?

The sound is growing on me. I could still take granny to church without raising any eyebrows as long as I kept my foot out of it.
With the stock muffler, during acceleration all I could hear was the Airaid Jr. This Jones 2590 is just loud enough to cover the intake noise.

 

[DPGDirk]

I like the sound of that. (No pun intended...maybe)

Jenna, what do you think about running the magnaflow Y-pipe and that Jones muffler, but not replacing the stock exhaust manifolds with headers? How much difference do the LT's really make over the stock manifolds?

Just thinking these exhaust mods and a mild cam along with your tune might make a nice difference without having to mess with headers.

Also, are there some good options for a full exhaust system out there? LT's all the way back replaced? In the jeep world, I usually have a good local shop fab up my exhaust, but you can't gain much in performance from a I-6 with exhaust mods. I'd rather have a nice pre-made system with mandrel bends, since none of the muffler shops around here have a mandrel bender.

My Yukon is 4WD too, and it appears that not all headers/exhaust systems fit real well.

It's an '03 Yukon with the L59 5.3....

Thanks everyone for any info!

 

[JennaBear]

I don't know much about the Jones muffler. Are they chambered? I typically stay away from chambered mufflers (ie. Flowmaster) as they tend to hurt HP and MPGs.

LTs and the Magnaflow Y pipe would definitely net you some gains. If you are looking to save some pennies, I would pass on the muffler, and just go with LTs and Y pipe. If you are still looking for some new accoustics, then pull the trigger on a new muffler (I would recommend a Magnaflow for best bang for your buck).

 

[DPGDirk]

Looks like the Jones mufflers are not chambered. Jough's posts led me to look at them. Outflowed the MF muffler by appx 100cfm.

I'm confused by all the info I'm seeing on the Y-Pipes too. Don't know whether to go with a cat-less Y or with that magnaflow version and which bolts up to headers or stock exhaust or both.

Jenna, I see on your sight that BB is coming to Ft. Worth in Sept/October?
Any date set yet?

 

[jough]

The Jones muffler is a Magnaflow copy, so it is not chambered. It has a perforated straight thru tube.

 

[JennaBear]

Looks like the Jones mufflers are not chambered. Jough's posts led me to look at them. Outflowed the MF muffler by appx 100cfm.

I'm confused by all the info I'm seeing on the Y-Pipes too. Don't know whether to go with a cat-less Y or with that magnaflow version and which bolts up to headers or stock exhaust or both.

Jenna, I see on your sight that BB is coming to Ft. Worth in Sept/October?
Any date set yet?

I believe the guys are locking in the dates this week.

 

[DPGDirk]

I believe the guys are locking in the dates this week.

Very cool. I hope it is not the weekend of the 10th.

I would come down for this event...

P.S. Any plans to come to the Wichita or KC areas in Kansas/MO?