A corvette with old-tech glasspacks
Thread Starter
Melting Slicks
Joined: May 2002
Posts: 2,670
Likes: 4
From: Severna Park MD
A corvette with old-tech glasspacks
I had to do a dyno pull this week just because not knowing the result of my latest mod was killing me. I have a custom 3" exhaust with X-Pipe behind LT headers and high-flow cats. The mufflers are plain vanilla Dynomax bullet glass packs. Just old-tech with fiberglass in tubes. I have gotten a lot of comments about the sound of my car, and strange looks when I say its just old style glass packs.
Here are a couple clips from that run. The first is just a warmup sequence and the second is my third pull.
You probably should save the file by right click, save target as.
A warmup just going through the gears
A dyno pull taken to 6200
This exhaust setup is not the cheap way out. Parts and labor for every thing behind the cats was $780.00. Add the price of the headers and cats and I have about $1800 into exhaust upgrades for about a 50 lb ft torque boost. I have single angle cut tips so I get disapproving looks from the traditionalists. Who cares? My car sounds like a traditional hot rod.
Here are a couple clips from that run. The first is just a warmup sequence and the second is my third pull.
You probably should save the file by right click, save target as.
A warmup just going through the gears
A dyno pull taken to 6200
This exhaust setup is not the cheap way out. Parts and labor for every thing behind the cats was $780.00. Add the price of the headers and cats and I have about $1800 into exhaust upgrades for about a 50 lb ft torque boost. I have single angle cut tips so I get disapproving looks from the traditionalists. Who cares? My car sounds like a traditional hot rod.
Thread Starter
Melting Slicks
Joined: May 2002
Posts: 2,670
Likes: 4
From: Severna Park MD
Originally Posted by bogus
It sounds good.
That dyno pull kept going! That's 6200? Damn... sounded like 8k!!!!
The only problem is knowing the actual volume of the sound. The tone sounds GREAT!
That dyno pull kept going! That's 6200? Damn... sounded like 8k!!!!
The only problem is knowing the actual volume of the sound. The tone sounds GREAT!
Maybe it did go beyond 6200 on that pull. He lost his tach signal during the run so I'm not sure how high it went.
Team Owner
Joined: Dec 1999
Posts: 34,873
Likes: 487
From: Lacey WA RVN 68-69
NCM Sinkhole Donor
Glass packs can be really loud and they are of course "old school"
Back around 67, I had a '57 Chevy with a 235 straight six. I found a set of Fenton split manifolds which were sort of like cast iron headers. These were a nice flowing manifold with each piece having it's own exhaust pipe. I ran a dual exhaust with a pair of 14" long 2" core glass packs. Those would wake the dead!
I almost got a ticket from the WA State Patrol once on I -5 for loud exhaust. I was headed southbound in my 57 doing about 85 in a 70 and he was headed north. As soon as I saw him, I took my foot off the gas and he heard those pipes bark across 200 feet of freeway. He turned around and pulled me over and asked to hear the exhaust. With his ticket book in hand, I told him I was going into the Army that weekend (I had signed my enlistment papers that morning!) and I wouldn't be around to pay the fine. So he let me off with a warning to drive slow and not hammer the throttle.
If you want glass packs to be a bit louder without waiting for the fiberglass to burn out, just pour a bit of kerosene down them and light a fire. A couple minutes later and you will have a "well-seasoned" set of mufflers.
Back around 67, I had a '57 Chevy with a 235 straight six. I found a set of Fenton split manifolds which were sort of like cast iron headers. These were a nice flowing manifold with each piece having it's own exhaust pipe. I ran a dual exhaust with a pair of 14" long 2" core glass packs. Those would wake the dead!
I almost got a ticket from the WA State Patrol once on I -5 for loud exhaust. I was headed southbound in my 57 doing about 85 in a 70 and he was headed north. As soon as I saw him, I took my foot off the gas and he heard those pipes bark across 200 feet of freeway. He turned around and pulled me over and asked to hear the exhaust. With his ticket book in hand, I told him I was going into the Army that weekend (I had signed my enlistment papers that morning!) and I wouldn't be around to pay the fine. So he let me off with a warning to drive slow and not hammer the throttle.
If you want glass packs to be a bit louder without waiting for the fiberglass to burn out, just pour a bit of kerosene down them and light a fire. A couple minutes later and you will have a "well-seasoned" set of mufflers.
Large Impressive Member
Joined: Jul 2003
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From: Good health is merely the slowest possible rate at which one can die
St. Jude Donor '04-'05-'06-'07
Sounded pretty good. If you like it, screw anyone else anyway. My next dyno run will be through better headers and a Power Effects exhaust system so it'll be wide open exhaust for all practical purposes.
Thread Starter
Melting Slicks
Joined: May 2002
Posts: 2,670
Likes: 4
From: Severna Park MD
Originally Posted by c4cruiser
Glass packs can be really loud and they are of course "old school"
If you want glass packs to be a bit louder without waiting for the fiberglass to burn out, just pour a bit of kerosene down them and light a fire. A couple minutes later and you will have a "well-seasoned" set of mufflers.
If you want glass packs to be a bit louder without waiting for the fiberglass to burn out, just pour a bit of kerosene down them and light a fire. A couple minutes later and you will have a "well-seasoned" set of mufflers.
Here's the look I get from the purists.
Team Owner
Joined: Dec 1999
Posts: 34,873
Likes: 487
From: Lacey WA RVN 68-69
NCM Sinkhole Donor
No, do it before you install 'em! 
One of the best sounding set of glass packs I had ever bought were just glasspack "blanks" about 28" long I got at Midas. The were the weld-in style and they had a sort of turbine-style disc in the front. Apparently it was supposed to get the exhaust gases spinning as it went thru the muffler and made them a bit quiteter. Had a set on my 66 396 Impala SS with 4-speed and they sounded very nice. Not blatty like some of the early Smithy's.
One of the best sounding set of glass packs I had ever bought were just glasspack "blanks" about 28" long I got at Midas. The were the weld-in style and they had a sort of turbine-style disc in the front. Apparently it was supposed to get the exhaust gases spinning as it went thru the muffler and made them a bit quiteter. Had a set on my 66 396 Impala SS with 4-speed and they sounded very nice. Not blatty like some of the early Smithy's.
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Melting Slicks
Joined: Oct 2000
Posts: 3,426
Likes: 4
From: Heidelberg PA
Cruise-In V Veteran
Old school is good school. Your car sounds Bad a@@ed. As other on this board have mentioned - do it the way you like it it and tell purists to go pound salt.
I get compliments all the time and my car is far from quite - on a quite night you can here me coming at least 2 to 3 city blocks away and I love it.
Corvette kid - If you like to hear your engine rumble - you will be impressed with the power effects.
I get compliments all the time and my car is far from quite - on a quite night you can here me coming at least 2 to 3 city blocks away and I love it.
Corvette kid - If you like to hear your engine rumble - you will be impressed with the power effects.
Thread Starter
Melting Slicks
Joined: May 2002
Posts: 2,670
Likes: 4
From: Severna Park MD
Originally Posted by HeeHaw89
hey - where do you do your dyno pulls? I'm in Baltimore as well and was looking for somewhere to take mine.
thanks
thanks
This was done at Springfield Motorsports in Springfield VA. They are a Mustang rodding shop with a Dynotech. The guy running the dyno has a Camaro along with all his friends so I didn't get any grief from them.
The owner of the shop is printing money with the rich suburban VA kids bringing him Mustangs. They do a lot of outrageous cars, mostly the pushrod 302s.
There are shops in Maryland but I don't know enough to make a recommendation. Somebody here in MD f'ed up a racing Z06 and password locked the tables, and I don't know who it was. So I make the drive to VA.
Melting Slicks
Joined: May 2001
Posts: 3,270
Likes: 26
From: Winchester VA
Cruise-In V Veteran
I would agree that the capture does not do a very good job.
I told Chuck the day we rented out MIR how good that thing sounded going down the track. It is crisp and loud, like hearing each cylinder fire.
You'll have to make it out to Mason Dixon this year.
I told Chuck the day we rented out MIR how good that thing sounded going down the track. It is crisp and loud, like hearing each cylinder fire.
You'll have to make it out to Mason Dixon this year.
Thread Starter
Melting Slicks
Joined: May 2002
Posts: 2,670
Likes: 4
From: Severna Park MD
Originally Posted by RainDelay
I would agree that the capture does not do a very good job.
I told Chuck the day we rented out MIR how good that thing sounded going down the track. It is crisp and loud, like hearing each cylinder fire.
You'll have to make it out to Mason Dixon this year.
I told Chuck the day we rented out MIR how good that thing sounded going down the track. It is crisp and loud, like hearing each cylinder fire.
You'll have to make it out to Mason Dixon this year.
Now if only Mason Dixon reversed the track so it runs downhill instead of uphill we could get some of those E-town times up there.
Thread Starter
Melting Slicks
Joined: May 2002
Posts: 2,670
Likes: 4
From: Severna Park MD
Originally Posted by jerkyboy
That exhaust sounds great!!! What happened to John? Haven't been down to Dynotech in a while
Race Director
Joined: Feb 2003
Posts: 11,672
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From: Lake Wylie SC
Originally Posted by Corvette Kid NC
Sounded pretty good. If you like it, screw anyone else anyway. My next dyno run will be through better headers and a Power Effects exhaust system so it'll be wide open exhaust for all practical purposes.
Large Impressive Member
Joined: Jul 2003
Posts: 65,811
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From: Good health is merely the slowest possible rate at which one can die
St. Jude Donor '04-'05-'06-'07
Originally Posted by Strick
Wow, you're going with the Power Effects!!!!? Preacher has those and they sound good.