The 1947 - Present Chevrolet & GMC Truck Message Board Network







Register or Log In To remove these advertisements.

Go Back   The 1947 - Present Chevrolet & GMC Truck Message Board Network > 47 - Current classic GM Trucks > The 1973 - 1987 Chevrolet & GMC Squarebody Pickups Message Board

Web 67-72chevytrucks.com


Reply
 
Thread Tools Display Modes
Old 11-17-2014, 07:55 PM   #1
torpedo
Registered User
 
torpedo's Avatar
 
Join Date: Nov 2014
Location: Louisburg, Ks
Posts: 17
Exhaust

I have a 1978 K-20 with a 454, it has true duals coming straight off the headers (one side has a muffler and the other one rusted off and I just haven't fixed it yet) that end a little in front of the rear axle. My brother and a friend's dad told me that 2 12" glasspacks would sound really nice, it's already pretty loud already and another friend said they'd probably actually make it quieter even though they're glasspacks. I was planning on just getting the 2 12" glasspacks but I was just wanting to see if anyone else knew if anything else would sound better
torpedo is offline   Reply With Quote
Old 11-17-2014, 08:41 PM   #2
MidwestMan
Registered User
 
MidwestMan's Avatar
 
Join Date: Jul 2014
Location: Kansas
Posts: 53
Re: Exhaust

Flowmasters, I have glass packs now and hate them with a passion.
MidwestMan is offline   Reply With Quote
Old 11-17-2014, 09:25 PM   #3
torpedo
Registered User
 
torpedo's Avatar
 
Join Date: Nov 2014
Location: Louisburg, Ks
Posts: 17
Re: Exhaust

Quote:
Originally Posted by MidwestMan View Post
Flowmasters, I have glass packs now and hate them with a passion.
What don't you like about glasspacks?
torpedo is offline   Reply With Quote
Old 11-17-2014, 09:41 PM   #4
Corts60
Just here to tinker
 
Corts60's Avatar
 
Join Date: Jun 2008
Location: Holland, MI
Posts: 3,697
Re: Exhaust

If you want that flow master sound but only want to spend under $100, get some Thrush welded mufflers from Napa. $30 each. They sound fantastic I think and they are all welded construction.
Corts60 is offline   Reply With Quote
Old 11-17-2014, 10:06 PM   #5
MidwestMan
Registered User
 
MidwestMan's Avatar
 
Join Date: Jul 2014
Location: Kansas
Posts: 53
Re: Exhaust

Quote:
Originally Posted by torpedo View Post
What don't you like about glasspacks?
The sound in general, the popping and that horrible farm truck twang. Had true duals with 40 series flows dumped before the rear end on my 98 silverado. Loud enough for me, nice growl, no popping.
MidwestMan is offline   Reply With Quote
Old 11-17-2014, 10:10 PM   #6
torpedo
Registered User
 
torpedo's Avatar
 
Join Date: Nov 2014
Location: Louisburg, Ks
Posts: 17
Re: Exhaust

Quote:
Originally Posted by MidwestMan View Post
The sound in general, the popping and that horrible farm truck twang. Had true duals with 40 series flows dumped before the rear end on my 98 silverado. Loud enough for me, nice growl, no popping.
She is a farm truck when she's not taking me to school or work but from some of the videos on youtube the 40 series sounds better, I think I need to see some more though to make a decision
torpedo is offline   Reply With Quote
Old 11-18-2014, 12:44 AM   #7
mattybilt79
Registered User
 
Join Date: Nov 2014
Location: Arizona mostly
Posts: 114
Wink Re: Exhaust

My truck has dual glass packs on it and I really can't stand them at idle. Sounds like I have an exhaust leak but I don't and fairly quiet. Do like how they sound going down the road cause they are obnoxiously loud. My current 454 came with Doug thorley tri y headers already on it. Little pricey at like 650 for them new, I paid 750 for the whole motor! Wife's Tahoe has a flowy on it, thought it was neat to set off alarms in parking garages at first but have grown out of that.
mattybilt79 is offline   Reply With Quote
Old 11-17-2014, 08:41 PM   #8
natedogg
Registered User
 
Join Date: Dec 2013
Location: West, TN
Posts: 312
Re: Exhaust

I have headers with strait pipes and dual flowmasters on my 85 with a 305. Its not loud, but sounds nice and throaty. I had a 2004 Silverado with 5.3 and a previous owner put glass packs on it and it was loud and popped when I let off the gas and slowed down. Took it to exhaust shop and replaced it with a single flowmaster and it sounded a lot better. Hope this helps.
natedogg is offline   Reply With Quote
Old 11-17-2014, 09:15 PM   #9
torpedo
Registered User
 
torpedo's Avatar
 
Join Date: Nov 2014
Location: Louisburg, Ks
Posts: 17
Re: Exhaust

What would be some good headers to get? The muffler shop told me my exhaust needed completely redone but they wanted $500 to do it so my dad said screw that, if I do need new headers what would be the ones to go with?
torpedo is offline   Reply With Quote
Old 11-17-2014, 09:18 PM   #10
torpedo
Registered User
 
torpedo's Avatar
 
Join Date: Nov 2014
Location: Louisburg, Ks
Posts: 17
Re: Exhaust

Quote:
Originally Posted by natedogg View Post
I have headers with strait pipes and dual flowmasters on my 85 with a 305. Its not loud, but sounds nice and throaty. I had a 2004 Silverado with 5.3 and a previous owner put glass packs on it and it was loud and popped when I let off the gas and slowed down. Took it to exhaust shop and replaced it with a single flowmaster and it sounded a lot better. Hope this helps.

What would be some good headers to get? The muffler shop told me my exhaust needed completely redone but they wanted $500 to do it so my dad said screw that, if I do need new headers what would be the ones to go with?
torpedo is offline   Reply With Quote
Old 11-17-2014, 08:46 PM   #11
83swb
Registered User
 
Join Date: Sep 2012
Location: CT
Posts: 133
Re: Exhaust

Any muffler will reduce noise, hence "muffler", especially considering your only running one.
It's all about personal taste, in my opinion you should spend some time on youtube searching around for the sound your looking for. You have more than a few options.
83swb is offline   Reply With Quote
Old 11-17-2014, 08:49 PM   #12
torpedo
Registered User
 
torpedo's Avatar
 
Join Date: Nov 2014
Location: Louisburg, Ks
Posts: 17
Re: Exhaust

I've seen some people say flowmasters are the way to go and some people swear by glasspacks
torpedo is offline   Reply With Quote
Old 11-17-2014, 08:55 PM   #13
mongoose
Registered User
 
mongoose's Avatar
 
Join Date: Feb 2009
Location: slurrey, bc.
Posts: 1,134
Re: Exhaust

anything sound better than a glasspack.. then again most things sound better than a flowmaster.. its your truck.. make it sound how you want it to.
__________________
-'73 c/10 - Low with Go - will be complete... probably never.
-'90 2wd Blazer - well... soon enough anyways.
-'84 SWB - the daily gas guzzler.
mongoose is offline   Reply With Quote
Old 11-18-2014, 01:25 AM   #14
Gregski
Post Whore
 
Gregski's Avatar
 
Join Date: Aug 2014
Location: Sacramento, CA
Posts: 10,868
Re: Exhaust

Quote:
Originally Posted by torpedo View Post
I was just wanting to see if anyone else knew if anything else would sound better
Depends is a good answer until you tell us what you mean by better. For example to a mechanic to tune your car, stock is "better" as he knows what it should or shouldn't sound like. However better to my wife would mean "quieter" however better than stock to me would mean deeper rumble, in which case I would go for Flowmaster 40s. If you want a bit higher pitch sound than the glass packs, are "better".

Not being a smart ass, just trying to help.
Gregski is offline   Reply With Quote
Old 11-18-2014, 10:48 PM   #15
torpedo
Registered User
 
torpedo's Avatar
 
Join Date: Nov 2014
Location: Louisburg, Ks
Posts: 17
Re: Exhaust

Quote:
Originally Posted by Gregski View Post
Depends is a good answer until you tell us what you mean by better.
I'd kinda like for it to have a nice rumble at an idle, also I just want it to sound smoother. One straight pipe and one with a muffler sounds kinda weird as you can imagine. I was thinking about cutting the muffler off and seeing how that sounds until I decide on the new ones. I like the glasspacks that I've seen on youtube but I'd like to see some thrush welds and I can't find any videos of them
torpedo is offline   Reply With Quote
Old 11-18-2014, 04:24 AM   #16
Your41Plague12
Registered User
 
Your41Plague12's Avatar
 
Join Date: Dec 2010
Location: Pittsburgh, PA
Posts: 1,009
Re: Exhaust

Thrush Welded, all day. Cheaper than a Flowmaster, better sound (to me; "better" is subjective), and no annoying drone inside the cab like every Flowmaster causes.
__________________
Steve
Member of the Foot Pedal Club
'83 Chevy K20: 6" Rough Country, 3" Performance Accessories BL,
Bushwacker Cutouts, 38x15.50 Mickey Thompson Baja Claws,
350 HP 350 crate engine from Jegs, Turbo 400
Your41Plague12 is offline   Reply With Quote
Old 11-18-2014, 12:59 PM   #17
cadillac_al
Registered User
 
Join Date: Oct 2013
Location: Maine
Posts: 2,376
Re: Exhaust

Quote:
Originally Posted by Your41Plague12 View Post
Thrush Welded, all day. Cheaper than a Flowmaster, better sound (to me; "better" is subjective), and no annoying drone inside the cab like every Flowmaster causes.
Those will be my next mufflers. They sound better than Flowmasters. Up here glasspacks are illegal because they last too long. I'm old so I like the machine gun sound of glasspacks. On my street driven GMC I have gone through 2 sets of mufflers in 4 years. My plow truck did street duty for 12 years and plow duty for the last 10 on the same glasspacks. I may be forced to register my street truck as an antique and run glasspacks just so I don't have to replace them so often. I'll give the Thrush welded's a try first though.
__________________
76 Chevy K20
76 GMC K15
77 Chevy C10
77 Chevy K10
cadillac_al is offline   Reply With Quote
Old 11-18-2014, 07:05 AM   #18
walls
Registered User
 
Join Date: Aug 2011
Location: Green Lane PA
Posts: 55
Re: Exhaust

My opinion is if your car/truck is 65 or older, it should have glasspacks. Steelpacks if it's got a flathead or it's a post war style car.
Flowmasters and turbo mufflers fit better to me on a muscle car/truck. I put these trucks in that category.
On a side note, I believe the loudness of the exhaust should be in direct relation to the performance level of the engine.
Meaning, if your engine is stock, put a muffler on that has a nice rumble.
If you've got a built motor with a crazy cam, put some on that'll piss off the neighbors.
walls is offline   Reply With Quote
Old 11-18-2014, 11:13 AM   #19
77K10Silverado
Registered User
 
77K10Silverado's Avatar
 
Join Date: Jul 2014
Location: Winston-Salem, NC
Posts: 561
Re: Exhaust

Well said walls!
77K10Silverado is offline   Reply With Quote
Old 11-18-2014, 02:57 PM   #20
Orion88
Registered User
 
Orion88's Avatar
 
Join Date: Feb 2014
Location: Bloomington, IN
Posts: 164
Re: Exhaust

What about Dynomax Race Bullets? I think the Muscle Truck from Roadkill runs 3" dual exhaust to 12" Dynomax Race Bullets and that truck arguably has the best sounding exhaust on the planet for a street truck. Then again they are running a hyped up LS under the hood, which have their own signature sound on their own. Is anyone running these mufflers on their truck with an original style motor?
__________________
You gotta have fun while you're little!!
Orion88 is offline   Reply With Quote
Old 11-18-2014, 09:33 PM   #21
donut
Registered User
 
donut's Avatar
 
Join Date: Aug 2009
Location: S.C.
Posts: 1,593
Re: Exhaust

Sound is subjective, IMO, hang a good sounding muffler on a stock vehicle you may as well get a neon sign that says "poser". Just my opinion, don't flame me for it.
Being a little older and spending 1-8hrs behind the wheel....
I'm old enough now that not having a full exhaust is a temporary thing.

I actually like the glasspacks coupled with a full exhaust (was about all you could get back in the day,). Like mentioned, they do last forever. Flip side to that is the pipe doesn't. I also lived in Maine and grew to like the sound of a cheap turbo muffler. Yes, I'd have to replace them yearly, but if the pipe wasn't OEM, it had to be replaced about every 2 years anyway.

My dually currently has glasspacks and duals. Actually what O'Reillys said was replacement for the truck. They were on it, so they stay for now. My old K-20 had cheap turbo's, driver and a plow truck.
__________________
'86 C-30 dually, 454/tbh400
'73 K-20 350/350/205 (sold )

I'm kinda like duct tape- no real purpose, but handy to have around.
donut is offline   Reply With Quote
Old 11-18-2014, 10:23 PM   #22
motornut
78K & 79C Jimmys
 
motornut's Avatar
 
Join Date: Nov 2009
Location: Ottawa Ont CANADA
Posts: 7,901
Re: Exhaust

Well i'm running 2.25 true duals on my C/K Jimmys.
the K 78 has Cherry bombs with a 350,got a whole lot nicer with the tails replaced with turndowns.
the C 79 has Flowmasters 40s with a 305,(plus H pipe) dosn't sound stock.

If I didn't want a loud exhaust I'd go to Speedy! lol
kidding they built the 79s exhaust for about 6-700$.
but the C 78 burb had dynomaxs on it......couldn't talk till i had tails put on.
I've done the headers to 2.5 pipe, didn't seem as loud as 2.25 pipe,more rat tat tat
__________________
John
1978 GMCJimmy4X4-350/203
1979 GMCJimmy4X2-305/350
motornut is offline   Reply With Quote
Old 11-18-2014, 10:01 PM   #23
Oregoon
Roadside Rebuilder
 
Oregoon's Avatar
 
Join Date: Oct 2008
Location: Southeast Portland, OR
Posts: 421
Re: Exhaust

Totally subjective. I prefer a six to an eight--always have--and I like a split-header running into straight pipes with no crossover or balance tube, and no mufflers at all.

But I only like that on a rod or a custom.

For anything remotely daily-driver, give me a nice quiet exhaust system so I can listen to that lovely gear-whine my six makes!
Oregoon is offline   Reply With Quote
Old 12-08-2014, 05:26 PM   #24
trappermat
Registered User
 
Join Date: Sep 2013
Location: water, sd
Posts: 21
Re: Exhaust

Straight pipes anyone?
trappermat is offline   Reply With Quote
Reply

Bookmarks

Tags
1978, 454, exhaust, k20

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -4. The time now is 08:46 PM.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.
Copyright 1997-2022 67-72chevytrucks.com