Hi-flow muffler--What's everyone using?

[AndyS]

Funny you say that; I originally had a 40 series cat-back setup from Rusty's (with a turned down tip) on my '94 and it resonated like hell right at the rpm range where the tranny tries to keep the engine (no tach, but it sounds like around 2500rpm). Minimal power gain. Lots of noise gain. Very drone-ish with the OEM manifold.

I then replaced my down pipe from the OEM manifold to the converter with a 2.5" pipe to match the cat-back setup. No real difference in sound, and possibly a light improvement in power.

I then replace my converter with a CatCo 2.75" converter from Summit. Minimal power increase noticed, but deeper, louder sound with more resonance (due to the smaller converter volume; it's only a 14" I believe).

Just recently, I finally replaced my cracked OEM manifold with a Borla header, and without question, the tone changed (MUCH nicer sounding), the resonance is nearly eliminated, there is nociably more midrange power, and my mileage has improved. These last two items might also be due to the cracked manifold, but even just for the sound improvement I'd do it again.

If you're just doing a cat back setup, I'd avoid Rusty's (very cheap, which is why I bought it, but I had to do way too many adjustments to get it dg fit. Plus, the tubing is poor quality.). If you are bent on getting a Flowmaster, go with a delta series; they still sound great outside, and they really reduce interior resonance.

Andy

 

[FJH97XJ]

Had used Flowmaster & now I use DynoMax. Like the DynoMax alot & it's a straight thru type unlike the Flowmaster.

 

[btl_fed_xj]

I run a 40 series Flowmaster that has a dual exhaust set up with a split at the muffler. Sounds beautiful, couldn't ask for a better rumble but it is pretty quiet when I am on the highway. Cost me $225 including all the custom bending muffler and all. Good luck to ya!

Jamie

 

[Ted Z]

i run a 2 chamber Flowmaster..... Sweet... Your right a little loud at higher rpms....But its good to know it's workin hard

Loud Jeeps Save Lives

 

[Faux4X4]

I will put in another vote for Spintech, I have one and it sounds sweet. Just make sure you really like the sound of your jeep cus thats all you are going to hear.

 

[yellowxj]

Like my spintech too. Have it turned out the side with no cat. Sounds like a xross between a glass pack and flowmaster to me. Flows great. Doesnt resonate much inside. It doesnt sound like everyone elses glasspack/flowmaster/borla/dynomax.

 

[Weasel]

Dynomax ultraflow. I have had people tell me it sounds better then their Flowmasters. I've never really compared the two though. It's a tough muffler...my cat has been dented up pretty good but the muffler is still looking brand new.

 

[XJFREK]

I put the flowmaster 3 chamber on about a year before Rusty came out with his cat-back kit. I wanted to go 2.5 in all the way back but the local shop said the stock pipe was stainless and would last forever. So when Rusty's kit came out I just ordered the pipe and had that put on. That's been about 2 years ago. 3 for the muffler. So far, everything is holding up through the Indiana winters, although the chrome tip that came with the pipe looks like hell. I enjoy the rumble, I don't find it any more annoying than the tire or wind noise produced by my jeep. And it's a very distinctive tone. I would not want to go any louder though.

 

[Judd W. VA]

Hey MudDawg.....

Can't believe someone alive is aware of those Corvair Turbocharger mufflers!! Those were the first performance mufflers i used back in the 70's on my GTO!! You are correct, they were really good mufflers with 2.5" in and out and were pretty small and the sound was really good on a V8. Lasted a while too-

On my '98 got the Rusty's catback with the Flowmaster 50 Series and is plenty loud enough. The 40 is way too loud for this straight-6 engine. Sounds too much like a UPS truck. I sure hope my cat-back doesn't rust out prematurely. Generally Flowmaster mufflers last a long time and this cat-back pipe is the aluminized type.

 

[erikrs301]

Thrush Glass pack, can't go wrong for $17

 

[Bones]

I have been through the Dynomax and Flow master set ups. The Dynomax had a great sound and all but didn't last worth a sh*t. The Flowmaster again had a good tone at the rear of the Jeep but I got tired of the resonance in the cab at cruising speed. So when the Flowmaster rusted out in about a year I went to a Full Boar "Quiet Boar" muffler. Still flows well and is as strong as the Flowmaster was but MUCH quieter in the cab. It lasted about 2 years. Next up is a cat and muffler replacement next month. I will be going back with the Full Boar. It's by far the best I've run to date.

I like the concept of the Borla cat back. I run a Borla header but for me the muffler and pipe are a bit expensive for something I'm going to pound on rocks.

Yep, It was too loud and I'm to D*mn old ...

Bones

 

[XJeacdabnow]

FLOWMASTER!!! Sweet sound and head turning loudness!!!! ALways a plus in a big truck!!

 

[BillR]

Thanks for all the help folks! I decided to go with Magnaflow, and had it installed today. It sounds nice without being too loud.

 

[Big Bear]

I love my Spin Tech. I sounds great and the new desighn is the thinnest most indestructable muffler on the market.

 

[CaptTrev]

1 vote for Borla cat back (stainless steel all the way)
and im running a carsound cat sonv. (also stainless steel)

LOVE the sound
low. deep. grumbly, but not crazy loud if u drive normally.
both items from truckperformance.com

 

[BLUTO]

exhaust choices

I'm also looking for a new XJ exhaust........
I'm running a Flowmaster 50 series on my 93 GMC 4x4 w/350 and no cat. It is 2 yrs old and doesn't appear to be rusting out any time soon. The resonance isn't a problem either, taking the cat off really made it sound tough! I did have a 40 series on a 99 Dodge 4x4 and it had terrible trsonance on the freeway.
As far as rusting goes....If your rig is a daily driver, you should have no trouble with a Flowmaster rusting through prematurely. It is when they sit for a few weeks at a time, that corrosion begins to become a problem. I don't drive my GMC everyday now and I've noticed a change of hue in the color of my muffler. I still give it another year at least.
Any muffler that uses fiberglass packing is going to burn/blow out and deteriate on you too.
Flowmaster now makes a 409 SS version of their 50 series, the MSRP is only about $15 more than the aluminized one (approx $130).
I talked to Rusty the other day, and he was unaware of the SS unit (it is right on Flowmaster's home page). Find a dealer thru Flowmaster and have a SS catback bent up for you. I may go that route if the guage isn't too thin.
Also, one of the reasons that Flowmasters are so tough on the trail is because the baffles are welded to both sides of the muffler...creating a "corrugated" like strenght.

BLUTO