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Old 04-29-2006, 05:01 PM   #1
nevada70chev
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glasspacks.....

is anyone runnin' glasspacks, what size? do you like 'em? too loud? good/bad and ugly? any pics? i need to replace the mufflers, blown out at the seams, so i'm lookin' for an inexpensive solution since gas is getting expensive i don't drive it that much. thanks.
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Old 04-29-2006, 05:17 PM   #2
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Re: glasspacks.....

I have them and I hate them.... they sound like an old tractor..... ill be putting flowmasters on it soon
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Old 04-29-2006, 05:26 PM   #3
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Re: glasspacks.....

Turbo's are another cheap solution. I think they are mellower than glasspacks.
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Old 04-29-2006, 05:40 PM   #4
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Re: glasspacks.....

I have the cherry bombs on my 84. I dont mine them at all. Kinda nice mellow tone.

The 67 has flows and they are a mufffler that if the truck is driven daily would mabye get to you.
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Old 04-29-2006, 05:53 PM   #5
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Re: glasspacks.....

thanks for the input, does anyone have pics? i will try and get a pic posted of what i want to replace....thanks.
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Old 04-29-2006, 06:44 PM   #6
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Re: glasspacks.....

I have 30" blanks, can't recall which mfr but it's the company that bought out Mitchell (many years ago). They had a nice deep, mellow rumble without being loud at all. After many years, they are getting a bit loud but still not too bad. If the muffler shop was closer, I'd get 'em replaced -- and I'd try to get the same thing. BTW no loud, sharp 'rap', ever. And no offense to anyone, but I don't care for the hollow, 'echo'chamber' sound of Flowmasters.
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Old 04-29-2006, 07:04 PM   #7
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Re: glasspacks.....

I might try glasspacks on our current project, but I think the common short ones are too loud, if you can find some nice long ones and run the exhaust back of the tires or out by rear bumper it might be pretty good, depends on motor and cam size somewhat too and if you have headers, etc, how loud it might be.
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Old 04-29-2006, 07:27 PM   #8
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Re: glasspacks.....

Used to own a 66 Chevy 1/2 ton. 283 2 brl with a 350 cam and 3 speed on the column. Stock exhaust manifolds with duals out past the rear bumper. I loved the glass packs on it. Would sound off when I wanted it to but not too loud in the cab
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Old 04-29-2006, 08:24 PM   #9
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Re: glasspacks.....

Before doing the engine build I had headers and 18" glass packs with a regular dual exhaust. It wasn't too loud. I think the average person who likes the rumble of a V-8 would like it and I got lots of complements.

My new exhaust is a different animal. This one has the engine in the sig with headers, 12" glass packs and a 2 1/2" exhaust. Let's just say it's not for everyone.

I think there are two kinds of glasspacks. One has perferations in the inner tube and the other has louvers. I think my old ones had the perferations but the new ones have the louvers. IIRC, the opening of the louvers are supposed to face the engine in order to muffle the sound. I figured this would only slow the exhaust velocity and rob HP so I turned them facing the back. Trust me when I say that they definitely give meaning to the phrase in my User Title.
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Old 04-29-2006, 08:32 PM   #10
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Re: glasspacks.....

I have them on my 79 Ford f350, I don't drive it much & seams were always splitting on reg muffs & turbos after just a yr or so. 5 years+ & still going strong. they sound OK, the longer ones are more mellow,,brian
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Old 04-29-2006, 10:45 PM   #11
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Re: glasspacks.....

To make glasspacks really loud, get them hot, then dump some water down in them. It breaks up the the inside to make them louder. I read that somwhere, maybe Hot Rod magazine.
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Old 04-29-2006, 10:59 PM   #12
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Re: glasspacks.....

OldYeller, that's excactly what I have on my 68. it can and does get somewhat annoying. but my 3 year old son seems to like it. he just sits there and smiles when riding with me. on the fun side is the kids with thier fart-can piped Hondas. I let 'er rip and they shut up in a hurry.
I am thinking of installing another pair up front and maybe even a balance tube.
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Old 04-29-2006, 11:09 PM   #13
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Re: glasspacks.....

I got some, they are really big in diameter, but i couldn't tell you a size, because my trucks in the shop. They aren't bad, but can get too loud when going up a hill while the truck is on boarderline of a gear change..

Heres the best pic i have


They have a good sound, and not quite as loud as flow masters..
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Old 04-30-2006, 12:10 AM   #14
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Re: glasspacks.....

I have 2 1/4" duals with 18" glasspacks on my truck that dump right behind the cab with turndowns. They are really loud when you get down on it or if you're driving it on the highway.(4.10 gears with 1:1 tranny, the engine really winds up!) They aren't real loud just cruising around, but just give it some gas and you'll be setting off car alarms.
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Old 04-30-2006, 12:17 AM   #15
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Re: glasspacks.....

I have the same setup on my truck.Too loud to hear the stereo in town,and waaayyy too loud on hte hiway IMO.If the pipe was longer,and they turned down at the rearend it wouldn't be bad.

If you place them in the middle of the pipe they sound like crap,pretty mellow old dumptruck sound on the end of the pipe.I'm going to flowmasters turned down at the rearend hopefully tomorrow,have the stuff,hoping for the time.

I would go for a nice pair of turbos,they sound better IMO.
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Old 04-30-2006, 02:22 AM   #16
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Re: glasspacks.....

well, you could modify the exhaust "design" from my truck to meet legality (at least here, mine's just shy of legal, haha)

straight off the headers, a few inches of pipe, short glasspacks, and a couple feet of pipe, then the duals end right before the end of the cab. With this truck pushing probably like 3500rpm doing like 55-65 (who knows how fast, with those old speedometers, and those steep gears) I had to yell at my buddy sitting right next to me, and I couldn't really think very well. To the point, with an exhaust like I got, your truck would be pretty loud. Sure, it sounds almost like a derby car, but hell, it gets the job done, the ears done, and everyone else either covering their ears, running for cover, or drooling over your exhaust.
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Old 04-30-2006, 08:17 AM   #17
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Re: glasspacks.....

I had a 71 GMC that I ran some 36" glasspacks on. I don't think you could fit them on a coil spring truck though. They started at the back of the cab and went up above the rearend at an angle. When they were new they were real quiet like a turbo. Once they had some miles on them they got a real sweet deep sound to them. They are a cheap alternative to flows if you have the room to run them.
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Old 04-30-2006, 12:58 PM   #18
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Re: glasspacks.....

Quote:
Originally Posted by JAKES 68GMC
To make glasspacks really loud, get them hot, then dump some water down in them. It breaks up the the inside to make them louder. I read that somwhere, maybe Hot Rod magazine.
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Old 04-30-2006, 01:02 PM   #19
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Re: glasspacks.....

Quote:
Originally Posted by nevada70chev
is anyone runnin' glasspacks, what size? do you like 'em? too loud? good/bad and ugly? any pics? i need to replace the mufflers, blown out at the seams, so i'm lookin' for an inexpensive solution since gas is getting expensive i don't drive it that much. thanks.
I ran headers with "Purple Hornies" on the truck for a little while. Pretty loud and as Longhorn Man noted some people like that ragged sound and some people hate it. I use these as my standard engine break-in setup, as bolt right to the collectors and you can string 'em on a bit of wire for a couple of hundred miles. Not a long-term solution IMHO, as they exit under the vehicle and we know that's not a Good Thing.

http://store.summitracing.com/egnsea...ts=false&N=115
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Old 04-30-2006, 01:35 PM   #20
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Thumbs up Re: glasspacks.....

I run the Force Pro Series mufflers. 29.88 ea from SUMMIT. They are 2 chamber like the super 40's. I run my exhaust straight out the rear. I have A fairly large cam. I really like the sound. Come on 29.88 ea from summit!! You cant go wrong.

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Old 05-01-2006, 09:07 PM   #21
nevada70chev
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Re: glasspacks.....

thanks for all input. the pipe from the header into the muffler is good (blown seams on muffler) and the pipe from the back of the muffler is also good. i'm trying to find the best sounding muffler with the correct dimension for an "easy" swap, if that is even possible. thanks again guys. we have a summit in town, maybe i'll go and take a look.
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Old 05-01-2006, 11:34 PM   #22
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Re: glasspacks.....

Quote:
Originally Posted by nevada70chev
we have a summit in town, maybe i'll go and take a look.
You lucky dog,no shipping and handling charges,how nice.

Good luck
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Old 05-02-2006, 07:16 AM   #23
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Re: glasspacks.....

Quote:
Originally Posted by Brainchild
You lucky dog,no shipping and handling charges,how nice.

Good luck
He'll have to pay sales tax though. It wouldn't take much sales tax to offset the 10 dollar handling charge Summit charges per order.

On subject though, I run 18 inch glasspacks on my beater. 15 bucks each at the muffler shop. I do all my own exhaust work, just buy pipe from the muffler shop, but he offered to sell me the packs as cheap as I could order them mailorder for. I'm very happy with them. I like them as well as any Flowmasters I've ever had.
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Old 05-02-2006, 02:00 PM   #24
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Re: glasspacks.....

I put a set of 30" cherry bombs on the flatbed. Sounds great with headers and the 396.
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Old 05-02-2006, 04:09 PM   #25
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Re: glasspacks.....

I used to have 12" glasspacks with headers and a 350 in my C10, along with 3"x24" tips at the end. It was really loud, but sounded too cackly. Not very mellow, and kinda annoying. Glasspacks sound OK if set up right, but don't go with short ones like 18" or 12". I've got Flowmasters on it now and it sounds much better, although it is equally as loud.
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