I'm looking to make my motor pretty quiet. Right now I'm running some Purple Hornies glasspacks... I love them to death, but my roomates and neighbors don't quite agree :D

In the past I have run turbo mufflers (Hooker Super Comps) and didn't like the way they sounded. I also don't like the typical "Flowmaster" sound, it's just too common. Since I moved to Georgia, it sounds like they're on every single car and truck, lol.

A while back I heard about someone (not here) talking about some kind of sleeper trick - mixing turbo mufflers with glasspacks to make them really quiet but still free-flowing. Does anyone have any input on this? I was thinking of aquiring Jeg's Dual Exhaust kit that comes with the 2.5" mandrel pipe and two turbo mufflers, and then jamming a pair of non-louvered, straight through glasspacks together into the system and adding an H-pipe.

Input?

gsgzlr, what power level is breathing through this system?

This is for the new motor I have been planning to build. All the parts for the motor are already here, I just need to build it. My goal is roughly 425 horsepower. Do you remember that long cam thread I had with UD Harold? That's the motor I'm going to be running.

::bump::

No suggestions? :D

x-pipe or single muffler w/a pair of 2 1/2 inlets and a single 3" tailpipe.

I would guess a muffler with alot of fiberglass, such as a Dynomax Ultraflow would quiet things down a bit. Maybe even use a glasspack afterwards as a resonator. graemlins/thumbsup.gif

An x-pipe, with no other changes to my exhaust, changed my true dual from a roaring monster that was loud you can get away with on the street IMHO into something people can't hear inside the house when I start it in the garage.
This is with 20" mufflers, so if I wanted to start scaring people again I could just go to a somewhat loud muffler.

I think x-pipes quiet things down a ton, but I am unsure I think the sound fits my car. Idle sounds great, but it sounds like a different motor when you step on it.. or, in my case ease into it because the kickdown sends the engine to the rev limit and the car goes nowhere..

Matt

Full tail pipes out the back will also help a bunch. Buy a muffler with the largest case that will fit under the car.

A straight through design like the Dynomax Ultraflows, Borla's, and Magnaflows have the greatest flow, but are not as quiet as a multi-pass style muffler. The trade-ff with a multi-pass muffler is they don't flow as well as a straight though design. I love the sound of my current 20" long Ultraflows and X-pipe with full tails.

I personally could never get used to or like the baffled style mufflers. Had one set of Flowmasters and never again.

What MadMarv said.

Keep the glasspacks and ad an X pipe. H pipe does not quiet.

I have Dynomax Hemi Turbos on my BBC. These flow real well and are quiet. No X or H, just good old fashioned headers and 2-1/2" duals w/ tailpipes. The Hemi Turbos are a big case and do not have the typical muted-glasspack sound of a conventional turbo. I love em.

I second the Dynomax Hemi series. I replaced my flowmasters with these am quite happy. If you do some research you will find that they flow quite well.

My exhaust is also equipped with the 20" case 3" pipe dynomax hemi super turbo which at 565hp showed zero hp/tq difference to a 14" (and very thin) spin tech muffler that was loud.
The only downside to the muffler is I blow them out every few years. You can tell when they die, its not a progressive loudness increase, usually one of the flow redirectors kicks the bed and you have to buy a new muffler (its not a "baffle" muffler, its like a straight through but the gas path is shaped like a z inside instead of straight).
But for the quiet, sound and price, and I don't mind throwing cash at this car when I can (not that it ever works like it could/should), like these mufflers alot.

I run them with an x pipe and 2" (too large) hooker super comp headers and full 3" tailpipes.
Decent muffler IMHO.

If you want loud with the x-pipe sound the small spin techs did sound nice though.

Matt

an H-pipe will quiet,it smoothes the exhaust pulses or combines them and it is quieter to the ear.