Tony

Looking in side a set of glass packs, i assume there is a correct way to install them regarding front and back...direction of flow
They have small cuts in them..
Should the open end of the cuts face the exhaust stream, in a way "scouping" up some of the exhaust flow as it passes by?

I would almost assume so in trying to think how they work, but i really dont know.

Im modifyng my cat bypass pipes to take a set.

Randy V

I've always wondered they call 'em 'glass packs'?

Is there glass packed in there? Fiberglass?

FlyingDog

They're packed with fiberglass. At least they used to be.

Scott Turnbull

My experience is dated, but yes there used to be fiberglass type fill in the muffler and the old ones I use to have did not have a direction of flow. (don’t know about the new stuff)

On a side note: an old hot rodder trick when public ordnances said "mufflers were required" and visual inspections were the only check - was to plug one end of the glass pack, fill it with gasoline, kerosene (some flammable liquid) let it soak in, dump out the excess then throw a match inside and burn the packing out. Instant straight through bwaaaaaaa!

I use to have two sets. One new un-blown out and one blown out. I would run the loud ones until the local cops would stop me and tell me to “fix them.” I would then put the new ones on, drive around nice and quite for a while and swap back to the blown out ones within a week or so depending on how mad they were!

SharkSkin

Tony, you should be able to mount them either way. With the scoops facing the engine, it should be somewhat quieter than if they were mounted in the opposite direction. Look at it as a BWAAAHHH level option.

928ntslow

<was to plug one end of the glass pack, fill it with gasoline, kerosene (some flammable liquid) let it soak in, dump out the excess then throw a match inside and burn the packing out>

Might want to add for the kids at home, that this is done when they are NOT installed on the vehicle

Tony, I recall them having a waaapy sound, giving a snap to the exhaust note. Sounds waves are trapped in the chamber and absorbed by the fiberglass. I believe there is (was) screening inside to hold the fiberglass against the chamber. You should be able to see right through them from either end. Shouldn't make a difference which way they mount, but I would assume as you, they scoop the exhaust stream to send it into the fiberglass to muffle it some. They all eventually burn out anyway. Having them so close to your engine will burn them out quicker.

Are they still Cherry Red??? The smog guys are going to have a good head scratch if they do visuals in NV. Get a can of hi heat silver engine paint and coat 'em. Sounds like you might be pulling a dummy cat switch. Do some welding of what might look like shields and run that dummy smog tube down there too. (he he...snicker* snort*)

H2

Sharkskin has it right. You can mount glasspacks either direction....with slightly differing results. If you install really short glass packs and remove the original muffler, I'd install them with the scoops facing the engine. I did this and the car is still too loud to listen to the stereo. But it sure sounds nice. Taking out the cats makes it even louder but a nice move powerwise I'd think. The Ott X-over is a great way to go. I wish I'd done that now....but you have to do a few things there to keep the sound down but performance will be up. Of course, this is Idaho and I'm not sure if many of the vehicles around ever bother replacing their mufflers when they fall off their rigs and we don't have CO testing, etc.

Harvey

Tony

At 9 bucks a piece its thecheapest apart Ive bought for the car!
I bought the 2 of the 12" ones on this page.
http://www.racerpartswholesale.com/tbolt1.htm


As far as the color, they are red but its nothing a can of zip strip or some time on the wire wheel couldnt take care off.

With the cats on my car it is quieter, obviously, but with the SC now, im missing that little bit of extra punch i had in the seat of the pants with the cat bypass. My hope is that these will cut the noise just a tad but still give me good exhaust flow. Looking straight through them, i think they should work OK.
Since they are pretty short, odds are they will go "scoup" forward. We'll see

ill post pics when its done.

Tony

Well they were here when i got home.

Prettty cool. Heres the plan.
Hack off the latter part of the "test pipe"
Take some Zipstrip and the wire wheel to the glass packs to get rid of the tell tale red paint.
Weld them up in place with a small cross support like on the test pipe.
Keep the air injection pipe in place

The questions as, as i posted earlier...which way to mount them. Openings towards the exhasut stream or away? The "pack area" is only 12" long.







#1 facing the exhasut stream....




#2 away from the exhasut stream.

T_MaX

With the scoops open forward, it will cut down a little more of the sound, but will reduce flow just a hair (you want notice it on the old ***-O-Meter).

I like mine facing forward, but that just me. You could lightly clamp them on, bolt the rest of the system on at give it a try both ways.

I'm going to be doing the same, but welding in a Dr. Gas X-over.

bcdavis

Hmmmmm...

The "away" version seems to show a nice spiral pattern, that may help increase
exhaust flow... Just like rifling in a gun barrel...

Bill Ball

The high temp fiberglass is available at motorcycle shops. Most MC mufflers use it. My Norton Commando got REALLY loud over the years. Took the end caps off and restuffed with the glass to make them bearable again. Some mufflers are not rebuildable.

T_MaX

Bill B., have you tried your new test pipe? I welded those tubs in with the opening facing forward.

Tony, keep in mind, with Bill's there will be a differance as his has three chambers that helps in cutting sound a bit more than a single chamber.

Bill Ball

Curtis:

Actually I didn't remember that you had stuck glass packs inside - I thought the cats were just cleaned out. That's actually good news as I was a bit afraid it was going to be too loud with my RMB. I will strap it on this weekend. THANKS!

FlyingDog

Tony, you should put a protective shield (like cats have) under them in case a suspicious statey goes looking under your car. Or does that only happen in VA?