Glass pack muffler Question

[cudabob496]

Putting these on one of my cars.  When you look down the muffler, you see little metal caves ( or scoops, or scallops) cut out of the inner piping side wall,
that direct sound into the fiberglass. But the sticker on the mufflers tells you to install mufflers with the little cave openings on the inner
side wall pointing to the rear of the car.   I've searched the net, and people are putting these mufflers on both ways.  Since there are about
100 of the little caves per muffler, it can make a big difference in flow, and noise cancellation.  Any thoughts as to whick is correct?>

http://www.ebay.com/itm/Two-2-Summit-Racing-630820-Muffler-Glasspack-3-Inlet-3-Outlet-Steel-Natural-/390938975674?pt=Motors_Car_Truck_Parts_Accessories&hash=item5b05c75dba&vxp=mtr

http://www.bing.com/images/search?q=glasspack+bullet+muffler&go=Submit&qs=n&form=QBIR&pq=glasspack+bullet+muffler&sc=0-14&sp=-1&sk=#view=detail&id=A1B5E0F8A9D9117EEA6D9B95045E8A6B2F95D6ED&selectedIndex=34

[Strawdawg]

That style is very restrictive.  Reversing them makes the problem even worse

[cudabob496]

That style is very restrictive.  Reversing them makes the problem even worse

Ya, i've got clearance issues on this 99 trans am, and have made my own X-pipe system. Being
a 5.7 liter LS1, and it being a 3 inch system, I'm hoping there is not too much restriction.

[downtime!]

Glass packs had their time and place, but muffler technology has changed. Look into a small case spiral flow muffler, like the Moroso units. They offer excellent flow, and low restriction. The sound is moderately "aggressive".

http://www.jegs.com/p/Moroso/Moroso-Spiral-Flow-Mufflers/744819/10002/-1?CAPCID=30632589191&cadevice=c&gclid=CNmz_tyxpcECFVFgMgodFGkAbQ&CA_6C15C=230006180000013578

[cudabob496]

Glass packs had their time and place, but muffler technology has changed. Look into a small case spiral flow muffler, like the Moroso units. They offer excellent flow, and low restriction. The sound is moderately "aggressive".

http://www.jegs.com/p/Moroso/Moroso-Spiral-Flow-Mufflers/744819/10002/-1?CAPCID=30632589191&cadevice=c&gclid=CNmz_tyxpcECFVFgMgodFGkAbQ&CA_6C15C=230006180000013578

thanks. contrary to the picture I provided of an interior of a glasspack, the small scoops inside these 3 inch Summit ones are arranged in a spiral, like the rifling of a gun barrel.  Must be some kinda flow advantage or something?

[Topcat]

Magnaflow's make straight thru mufflers. 2.5" and other sizes.

P/N:  10426, 10435, 10436,

http://www.magnaflow.com/02product/shopdisplayproducts_universal.asp

[DocMel]

I had set of Flows on my 440.  I went to glass packs, (header mounts), and I will not go back.  They sound good, and are maybe just a little louder than the Flows, if louder at all, but have better sound:  Seat of pants, I believe a little better in exh flow.  No resonance at any speed, but I still plan to get a cross over installed

[HP2]

I've got a set of Thrush Red Hot glass packs that I'm thinking I may add to the exhaust after the rear axle. I have some Summit welded two chambers (Flowmaster copies) that if you angle them slightly, you can see almost straight through them. I have sneaking suspicion they are going to be a bit loud, so I think the extra resonance dampening of the glass packs will help with highway drone.

[duodec]

I can't speak to the performance aspect since mine was still stock 318-2V when it had glass packs but... they were Walker Continentals and the sound was absolutely beautiful.  Not too loud, not rough and raspy, but it made that little engine sound like much more, and all so very mellow.  I've got an NOS set that I'm going to at least try on the car when its to that stage of rebuild. 

[cudabob496]

wow, I have a performance Y-pipe, headers, and single 3 inch exhaust, supposedly capable
of supporting 350 hp on this Trans Am.  But this 3 inch X pipe system with the glasspacks really upped the mid range
torque!  What a difference!!  I bought the Summit 3 inch X pipe system for it, for about $110, then
modified it to fit my car (instead of buying the $1500 pre-fabbed systems available).  I highly recommend an X pipe system!!  TTI says their system on a big
block is worth 15 hp over their H-pipe system.

can you say winter project?

http://www.summitracing.com/parts/sum-642130/overview/

Harbor Freight has these welders for $99!

http://www.bing.com/videos/search?q=how+use+a+flux+wire+welder&FORM=VIRE1#view=detail&mid=8E8CBC85C790CB94610C8E8CBC85C790CB94610C

[johannes]

..... I've searched the net, and people are putting these mufflers on both ways.  Since there are about
100 of the little caves per muffler, it can make a big difference in flow, and noise cancellation.  Any thoughts as to whick is correct?>

.... call SUMMIT RACING Tec support
Did you buy these ?? if so, please describe the sound maybe even post a "sound check" on youtube ?

[cudabob496]

.... call SUMMIT RACING Tec support
Did you buy these ?? if so, please describe the sound maybe even post a "sound check" on youtube ?

they sound really good.  But I use earplugs anyway, because it is loud, since I dump at the rear axel.
Installing them with the scoops facing forward would really reduce flow efficiency.  So I'm gonna stick
with how I have installed them, which is what the sticker on them said also, scoops facing towards rear of car,
so exhaust flows smoothly over them.  I'm sure there are guys running them backwards, and hurting their performace,
but don't know it.  If you run glasspacks, stick a flashlight up there and see!

[cudabob496]

.... call SUMMIT RACING Tec support
Did you buy these ?? if so, please describe the sound maybe even post a "sound check" on youtube ?

found this on Utube. There are many videos of Summit glasspacks, thought I don't know which ones are 12 inch long casings or 18 inch.
this sounds close to mine, though I have turn downs, so not as much noise goes out back.
https://www.youtube.com/watch?v=s6pomHilfBU

[Denison636]

https://vimeo.com/117073094
2-1/5" with headers

[The Cuda Guy]

https://vimeo.com/117073094
2-1/5" with headers

I love this set up!  Did you go with an H-pipe or X-pipe with this set up?

Don