What are Glasspacks

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Robert

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Nov 15, 1997, 3:00:00 AM11/15/97
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Maine Goodfellow wrote:
>
> What are they and what do they do?


Sometimes called "Cherry bombs" as well (manufacturer of this model
painted them red). Essentially they are roughly 18" long, 6" in
diameter (no tape measure, going by memory), not much in them. They
have a little bit of fiberglass packing on the inside and a free flowing
design (no baffles). They are LOUD. Did I mention...they are LOUD! My
friend had a 396 in his '66 Chevelle SS equipped with glass packs. You
could hear it 4 blocks away easily. This design isn't worth much these
days. Most engines require some back pressure to develop full HP.
There are so many companies on the market now that can improve HP while
keeping the noise level to a tolerable level. Glass packs would easily
get you a ticket for disturbing the peace! One major thing that sucked
about them is cops could hear you from a long distance. It was very
easy for them to find us. My friend got three tickets in a very short
period (before selling the car). They seem to draw cops from every
direction.

Robert

nos...@mdi.ca

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Nov 15, 1997, 3:00:00 AM11/15/97
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In <64irrk$s4j$1...@news.cy-net.net>, on 11/14/97
at 07:02 PM, "Maine Goodfellow" <mer...@txcyber.com> said:

>What are they and what do they do?

AFAIK they are a kind of stright through muffler using fiberglass to damp
the sound... AFAIK, they are VERY inefficient...

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LX Windsor

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Nov 16, 1997, 3:00:00 AM11/16/97
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Barry L. Van Hook wrote:

> Before there were turbo and turbo-style mufflers, performance mufflers
> were
> limited to two types: steel-packs (the famous Smitty's) and
> glasspacks.
> Glasspacks were the muffler of choice in the 1950's. They varied in
> length
> from about 22" up to 30" or so, and were about 4-5" in diameter.
> Construction
> was a round tube with a single inlet and outlet. Running the length
> of the
> muffler was a perforated central tube or baffle; fiberglass was packed
> into
> the space between the baffle and the shell.
> sniped for space...

> Barry #36
>
> Barry L. Van Hook (van...@asu.edu)
> Management Department, College of Business
> Arizona State University, Tempe, AZ 85287-4006
> Phone (602) 965-1217 FAX (602) 965-8314

According to todays tests, glass packs are a lot more inefficiant than
the newest chamber and turbo style mufflers.

--
89 5.0 LX HB K&N Competition Engineering Flow Master Mac
73 Charger 340Wedge New Process 4spd Chrysler 8.75/w 4.10 SureGrip
65 Thunderbird Town Landau FE390
63 Dodge Dart 413 Max Wedge 8bbl short ram

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nos...@mdi.ca

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Nov 16, 1997, 3:00:00 AM11/16/97
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In <vanhook.57...@asu.edu>, on 11/15/97
at 11:56 PM, van...@asu.edu (Barry L. Van Hook) said:

>As far as performance was concerned, who knows??? There were no dynos on
>every street corner back then. They were low restriction mufflers, so you
>know what that means for torque/horsepower at varying levels of rpm. I
>believe that JC Whitney still sells a variety of glasspacks.

Well, most because it causes little eddies of airflow inside the tube,
causing reversion and slowing down the exhaust, due to the uneven surface of
the tube that the exhaust must flow through. And I do not think it comes
close to any of today's high performance mufflers... Flowmaster, Borla,
whatever, you name it, it will be very likely to be capable of blowing the
glasspack away with ease...

0to60

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Nov 17, 1997, 3:00:00 AM11/17/97
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nos...@mdi.ca wrote:
> Well, most because it causes little eddies of airflow inside the tube,
> causing reversion and slowing down the exhaust, due to the uneven surface of
> the tube that the exhaust must flow through. And I do not think it comes
> close to any of today's high performance mufflers... Flowmaster, Borla,
> whatever, you name it, it will be very likely to be capable of blowing the
> glasspack away with ease...

I too have heard this. However, do the cherry bomb's eddies of airflow
add up to more restriction than the multiple chambers of the
Flowmaster? I doubt it. Without flow testing, we'll never know. But
I'm hard pressed to believe that today's high performance mufflers can
outflow what is essentially a straight tube.

Fred Kissel

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Nov 17, 1997, 3:00:00 AM11/17/97
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I'm with you on this. Any muff that you can see straight though is
going to flow better than one you can't. It's that whole distance
between two points thing, that and gasses changing direction.

Fred Kissel

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Nov 17, 1997, 3:00:00 AM11/17/97
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Thats funny, I've heard that Flowmasters were some of the poorest
flowing muffs around.

Noflow Masters?

>Well, most because it causes little eddies of airflow inside the tube,
>causing reversion and slowing down the exhaust, due to the uneven surface of
>the tube that the exhaust must flow through. And I do not think it comes
>close to any of today's high performance mufflers... Flowmaster, Borla,
>whatever, you name it, it will be very likely to be capable of blowing the
>glasspack away with ease...
>

nos...@mdi.ca

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Nov 17, 1997, 3:00:00 AM11/17/97
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In <34707be2...@news2.ibm.net>, on 11/17/97
at 05:17 PM, fred-...@usa.net (Fred Kissel) said:

>Thats funny, I've heard that Flowmasters were some of the poorest flowing
>muffs around.

Where did you hear that, and what was is compared to? a stright tube?

>Noflow Masters?

Well, you go ahead and try to tell them that, my hunch is that they will
bury you under a mountain of lab results that shows that the flowmaster are
at least pretty good...

Robert

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Nov 17, 1997, 3:00:00 AM11/17/97
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nos...@mdi.ca wrote:
>
> In <34707be2...@news2.ibm.net>, on 11/17/97
> at 05:17 PM, fred-...@usa.net (Fred Kissel) said:
>
> >Thats funny, I've heard that Flowmasters were some of the poorest flowing
> >muffs around.
>
> Where did you hear that, and what was is compared to? a stright tube?
>
> >Noflow Masters?
>
> Well, you go ahead and try to tell them that, my hunch is that they will
> bury you under a mountain of lab results that shows that the flowmaster are
> at least pretty good...


Flowmaster are a bad design. They don't know squat about the
placement of baffles to inhibit resonance at 2K-3K rpms. The stock
muffler actually gets QUIETER at this level (excellent noise cancelling
design). This is typically highway speed. You are finished rumbling
around town, now you want to go somewhere. So you head out on the hwy,
this is when Flowmaster get their loudest. Their design reminds me of
glasspack technology. People bought them because it was the only thing
on the market. The Flowmaster engineer (aka bubba the welder) should be
taken out and shot for the 2 chamber design. Worst money I EVER spend
on my previous Mustang. Yea they flow but they also SUCK!!! Check out
the Borlas...Sound better, flow as good, and don't resonate.

Robert-FL

QuickGT

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Nov 19, 1997, 3:00:00 AM11/19/97
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>From: fred-...@usa.net (Fred Kissel)

>Any muff that you can see straight though is
>going to flow better than one you can't.

>From: van...@asu.edu (Barry L. Van Hook)

>They were low restriction mufflers, so you
>know what that means for torque/horsepower at varying levels >of rpm.

>From: Robert <rc...@globe-net.net>

>Glass packs would easily
>get you a ticket for disturbing the peace!

>They seem to draw cops from every
>direction.

As I have stated before, I ran glasspacks with turndowns and off road H-pipe
(all 2 1/2") for almost a year. Never got a ticket, never had any problem
with the cops. I believe that the glasspacks may flow better, like an open
exhaust, i.e. racing. Why run an open exhaust? More flow means an increase
in high rpm horsepower and that is where you will see benefits. Torque
however will go down the shitter which I found out when I put my 2 cham
Flowmasters back on. For the power range of a street car, and the need for
low end torque, a "turbo" muffler is the way to go.


Quick GT '89 Mustang GT 300+hp

"If you got it, a truck brought it."

Dabieb

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Nov 19, 1997, 3:00:00 AM11/19/97
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NOT GLASSPACKS!!!!!!!! NO! DONT DO IT!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

QuickGT <qui...@aol.com> wrote in article
<19971119011...@ladder01.news.aol.com>...

dbug*

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Nov 19, 1997, 3:00:00 AM11/19/97
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On Mon, 17 Nov 1997 23:53:50 -0500, Robert <rc...@globe-net.net>
wrote:


I agree. The rumble resonance from the mufflers in the RPM range
where 95% of my driving is done is unacceptable with not only the
Flowmasters but, also the Dynomax. They flow well and are not loud
enough to get you a ticket if driven responsible but, I can't stand
the resonance which seems to get into the roof and pound me from all
directions. I just replaced the one on my truck with a 2 1/2x29"
glasspack. The fuel mileage went back up along with the bottom end
torque. That probably represents an increase in backpressure. Since
the fuel efficiency and torque went up, the engine must like whatever
benefit it got from a little back pressure. Fact of the matter is
that the Flowmaster was probably over scavenging which experienced
engine builders will tell you can be just as bad as not enough. The
scavenging should be tuned with the engine configuration. Anyway, the
rumble is gone and the deep engine sound is just barely noticeable in
the cab. I don't have to pull over for asperin every 2 hrs when on
the road.

0to60

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Nov 19, 1997, 3:00:00 AM11/19/97
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LX Windsor wrote:
> According to todays tests, glass packs are a lot more inefficiant than
> the newest chamber and turbo style mufflers.

We know this. However, these test are being performed by "turbo" style
muffler manufactuers.

But who cares? Face it, a muffler is more of a sound thing than a
performance thing. The best cat-back system around will only get you a
few hp on these modern pony cars. Get the muffler that sounds the best
to you.

LX Windsor

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Nov 20, 1997, 3:00:00 AM11/20/97
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nos...@mdi.ca wrote:

> Well, most because it causes little eddies of airflow inside the tube,
>
> causing reversion and slowing down the exhaust, due to the uneven
> surface of
> the tube that the exhaust must flow through. And I do not think it
> comes
> close to any of today's high performance mufflers... Flowmaster,
> Borla,
> whatever, you name it, it will be very likely to be capable of blowing
> the
> glasspack away with ease...
>

> ===Proud Member of Team OS/2, Team OS/2 at Taiwan, ICENews Beta
> Tester===
> ===================And Bovine Team Warped Key
> Crucher====================
> NUTS' Home Base
> US Mirror http://www.cybermail.net/~davidwei
> Taiwanese Mirror http://www.taconet.com.tw/~davidwei
> 光碟月刊 OS/2 技術編輯 <<>> Hope_Net CD-ROM Monthly, OS/2 Editor

Who's Eddie ??

LX Windsor

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Nov 20, 1997, 3:00:00 AM11/20/97
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Fred Kissel wrote:

> Thats funny, I've heard that Flowmasters were some of the poorest
> flowing muffs around.
>

> Noflow Masters?

Sounds like you've been listening to Flow masters competitors too
hard...

LX Windsor

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Nov 20, 1997, 3:00:00 AM11/20/97
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Robert wrote:

> Flowmaster are a bad design. They don't know squat about the
> placement of baffles to inhibit resonance at 2K-3K rpms.

Hmmm. Flow master invented the chamber style muffler. The have the
lasrgest, and most up to date tecnical testing lab of any company,
including Borla.

> The stock
> muffler actually gets QUIETER at this level (excellent noise
> cancelling
> design). This is typically highway speed. You are finished rumbling
> around town, now you want to go somewhere. So you head out on the hwy,
>
> this is when Flowmaster get their loudest.

My 2 chamber Flow masters are the quietst at highway speeds. The only
time they make less noise is at an idle. Mine peak at 1200 to 1500 rpms.

> Their design reminds me of
> glasspack technology. People bought them because it was the only
> thing
> on the market.

How? They are not even remotely similar.

> The Flowmaster engineer (aka bubba the welder) should be
> taken out and shot for the 2 chamber design. Worst money I EVER spend
>
> on my previous Mustang. Yea they flow but they also SUCK!!!

Suck? Suck how? Sounds like possibly you tried to collect on a warranty
or something and they said no. Bubba must know what he's doing, because
the proof is in the numbers.

> Check out
> the Borlas...Sound better, flow as good, and don't resonate.

Sound better?? Different maybe, definatly quieter, but Flow master is
the top seeling muffler, more people like it, ANY half assed hot rodder
can tel the sound of a Flow master from any other muffler, and EVERY
little deekwad muffler company that has a piece of sheetmetal to sell
compares themselves to Flow master.

>

> Robert-FL

LX Windsor

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Nov 20, 1997, 3:00:00 AM11/20/97
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0to60 wrote:

> I too have heard this. However, do the cherry bomb's eddies of
> airflow
> add up to more restriction than the multiple chambers of the
> Flowmaster? I doubt it. Without flow testing, we'll never know. But
>
> I'm hard pressed to believe that today's high performance mufflers can
>
> outflow what is essentially a straight tube.

That testing has already been done. Read 5.0 and MMFF. Yes, it does
apparently add up to more restriction than the chamber baffels.

nos...@mdi.ca

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Nov 20, 1997, 3:00:00 AM11/20/97
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In <34751483...@mindspring.com>, on 11/20/97
at 10:56 PM, LX Windsor <maxwedg...@mindspring.com> said:

>> I too have heard this. However, do the cherry bomb's eddies of
>> airflow
>> add up to more restriction than the multiple chambers of the
>> Flowmaster? I doubt it. Without flow testing, we'll never know. But
>>
>> I'm hard pressed to believe that today's high performance mufflers can
>>
>> outflow what is essentially a straight tube.

> That testing has already been done. Read 5.0 and MMFF. Yes, it does
>apparently add up to more restriction than the chamber baffels.

Eddie current of air causes reversion, which is much like a wall of air that
slows the exhaust gas... thus the restrictions... you don't have to hit a
solid metal wall to cause restriction, ya know... :)

LX Windsor

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Nov 21, 1997, 3:00:00 AM11/21/97
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nos...@mdi.ca wrote:

> Other than Glasspak mufflers, I don't have much against them... :)
>
> from what I saw in a lot of the testings, Borla often out flow just
> about
> everything in the test... Best selling or not (Win 95 is the best
> selling OS
> out there, would you put it head to head against other industrial
> strength
> OS that costs the same or less? I don't think so...) it is not a part
> of the
> performance benchmark, and performance benchmark have never inculde
> the
> sales count...


>
> ===Proud Member of Team OS/2, Team OS/2 at Taiwan, ICENews Beta
> Tester===
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> Crucher====================
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> US Mirror http://www.cybermail.net/~davidwei
> Taiwanese Mirror http://www.taconet.com.tw/~davidwei
> 光碟月刊 OS/2 技術編輯 <<>> Hope_Net CD-ROM Monthly, OS/2 Editor

Now you of all people should know that the Win 95 comparason is
totally different. Maybe it would be close if A) all new cars came with
Flow masters and Borla had to worry about getting people to change to
them. And/or you had to worry whether every other part on the car would
work properly if you switched from Flow to Borla. Yes I'm sure in some
cases the Borla flows better, in others maybe the Flow does. My point
was that with all that's out there more people CHOOSE the Flows over
everything else, Borla a close second. I think very little if anything
he said was justified, let alone correct.

LX Windsor

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Nov 21, 1997, 3:00:00 AM11/21/97
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nos...@mdi.ca wrote:

> Eddie current of air causes reversion, which is much like a wall of
> air that
> slows the exhaust gas... thus the restrictions... you don't have to
> hit a
> solid metal wall to cause restriction, ya know... :)
>

> ===Proud Member of Team OS/2, Team OS/2 at Taiwan, ICENews Beta
> Tester===
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> Crucher====================
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Hhhhhh, huh uhhhuh huh huh.... you thaid, gas! Huhu hhuh huh..

nos...@mdi.ca

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Nov 22, 1997, 3:00:00 AM11/22/97
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In <3475117E...@mindspring.com>, on 11/20/97
at 10:43 PM, LX Windsor <maxwedg...@mindspring.com> said:


> Who's Eddie ??

I'm not sure, but it is used to describe the circular motion of current, be
it electrical or air... and having several places that have eddie current in
the exhaust system isn't gonna help the flow of exhaust...

IMHO the best developed muffler will have SMOOTH surfaces inside itself,
which drastically reduces the formation of eddie current...

Boxtop427

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Dec 1, 1997, 3:00:00 AM12/1/97
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wouldn't i love to have the last word on this subject! It is one of my
favorite, and a sure way to agitate racers with too much money and pride tied
into their exhaust and decals. Honest testing will prove the top performance
of glasspacks versus chambered/turbo/what have you mufflers. The only two
tests ive seen that included glasspacks are an old hot rod (late 70's early
80's) and a super ford about ten years ago. Since then of course, flowmasters
and their competitors advertising accounts have become the only relevant
parameter in any magazines editorial policy. After carefully studying the
exhaust options on the market, I'm going with Hooker Max Flows with their 3" in
and out. Standard glasspacks arent available in that size, and the race
variety might not inhibit adequate dB's. The capabilities of the max flo are
due to a STRAIGHT THROUGH design that cant be exceeded by a chambered exhaust.
Anyone that feels otherwise has probably been watching to much tv, and may be
susceptible to buying swamp land.

LX Windsor

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Dec 2, 1997, 3:00:00 AM12/2/97
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Boxtop427 wrote:

The problem is all those holes and louvers cause so much turbulance
that you can FELL the difference between a galss pack and a flow
master. Do what you want, but flow masters and Borlas flow better than
glass packs.

--
89 5.0 LX HB K&N Competition Engineering Flow Master Mac

65 Thunderbird Town Landau FE390
63 Dodge Dart 413 Max Wedge 8bbl short ram

73 Dodge Charger 340 Wedge 4.10 Sure Grip New Process Flow master

FENATIC

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Dec 9, 1997, 3:00:00 AM12/9/97
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"The problem is all those holes and louvers cause so much turbulance
that you can FELL the difference between a galss pack and a flow
master. Do what you want, but flow masters and Borlas flow better than
glass packs."

Might want to call Super Ford and tell them their April 1990 dyno test was
rigged somehow. Pacesetter glasspacks beat all those cool mufflers by at
least 5 hp. It was an injected 5.0 mild motor, but the test seemed fair and,
well, definitive. As for sound quality, all a matter of taste. Why does my
raggedy machine get so many compliments on its sound? Now, if youve seen a
more recent test that included glasspacks, id love to know about it. Thanks.


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