Sidepipe GlassPack Vs. Reverse flow
Instructor
Joined: Jan 2008
Posts: 241
Likes: 42
From: Skaelskoer, Denmark
The sound level will of course depend on your choise of engine, but I think glasspacks are much louder than reverse flow.
I have a modified 427 bowtie L88 with hooker sidepipes. I tried glasspacks (3" ID), and it was laud as thunder (http://www.youtube.com/watch?v=c_9xpvaURUM). Then I installed reverse flows and the loudness dissapeared, and it sounded more "metallic". But the muffler was way too restrictive for the engine - it couldn´t get enough flow - so now I re-installed the glasspacks and welded in some race cones. The race cones took just an edge off the sound level, so I´m still looking for new setups.
If to choose glasspacks you could go for the one with smaller inner diameter which will lower the sound level too.
But anyway - if you do have an almost stock smallblock, the glasspacks migth be perfect and give a cool rumbble....
I have a modified 427 bowtie L88 with hooker sidepipes. I tried glasspacks (3" ID), and it was laud as thunder (http://www.youtube.com/watch?v=c_9xpvaURUM). Then I installed reverse flows and the loudness dissapeared, and it sounded more "metallic". But the muffler was way too restrictive for the engine - it couldn´t get enough flow - so now I re-installed the glasspacks and welded in some race cones. The race cones took just an edge off the sound level, so I´m still looking for new setups.
If to choose glasspacks you could go for the one with smaller inner diameter which will lower the sound level too.
But anyway - if you do have an almost stock smallblock, the glasspacks migth be perfect and give a cool rumbble....
Drifting
Joined: May 2007
Posts: 1,491
Likes: 2
From: North Royaton Ohio
Why would you want it quiet?
FWIW, I love my Spiral Turbo Baffles
http://www.spiralturbobaffles.com/
FWIW, I love my Spiral Turbo Baffles
http://www.spiralturbobaffles.com/
Thread Starter
Racer
Joined: Sep 2005
Posts: 359
Likes: 0
From: Shoemakersville Pa
Why would you want it quiet?
FWIW, I love my Spiral Turbo Baffles
http://www.spiralturbobaffles.com/
FWIW, I love my Spiral Turbo Baffles
http://www.spiralturbobaffles.com/
Le Mans Master
Joined: Apr 2000
Posts: 5,202
Likes: 10
From: cincinnati ohio
St. Jude Donor '09
Im not saying I want it quiet. I just want to be able to have a conversation with the passenger without yelling. I've tried the hooker max flows (to loud) STS baffles (sounded to tinny) sweet thunders (to loud). It seems theirs no middle of the road for my 427 w/460+HP. So Im going to try the reverse flows.
Years ago when I tried them for the first time on a very mild smallblock I dropped them in the side tubes, slipped the side tubes over the collectors (which was a pretty tight fit). For whatever reason I decided to fire the motor before I cranked down the clamps. I was surprised how quiet they were and ever so slightly I blipped the throttle....and blew both side tubes off! Hows that for back pressure?
Driving impressions were not good either, seat of the pants power was way down.
It your moneys, makes your choice
Thread Starter
Racer
Joined: Sep 2005
Posts: 359
Likes: 0
From: Shoemakersville Pa
Let me relate this little tale before you plop down your cash for the reverse flows. .
Years ago when I tried them for the first time on a very mild smallblock I dropped them in the side tubes, slipped the side tubes over the collectors (which was a pretty tight fit). For whatever reason I decided to fire the motor before I cranked down the clamps. I was surprised how quiet they were and ever so slightly I blipped the throttle....and blew both side tubes off! Hows that for back pressure?
Driving impressions were not good either, seat of the pants power was way down.
It your moneys, makes your choice
Years ago when I tried them for the first time on a very mild smallblock I dropped them in the side tubes, slipped the side tubes over the collectors (which was a pretty tight fit). For whatever reason I decided to fire the motor before I cranked down the clamps. I was surprised how quiet they were and ever so slightly I blipped the throttle....and blew both side tubes off! Hows that for back pressure?
Driving impressions were not good either, seat of the pants power was way down.
It your moneys, makes your choice
Yellow 72. Now I believe you, put reverse flows in yesterday (had to prove it to myself, its one of those stuborn dutch things if your not from Pa. you would'nt understand). Now its to quiet and the backpressure is exactly as you explained. Took it for a ride and it would'nt go. I had all the bolts tightened down and the pressure actually pushed the tubes back 3/8 of an inch I could tell that because I saw where the never-seize line was from installation.
Racer
Joined: Jan 2010
Posts: 367
Likes: 1
From: Christchurch Canterbury
Yellow 72. Now I believe you, put reverse flows in yesterday (had to prove it to myself, its one of those stuborn dutch things if your not from Pa. you would'nt understand). Now its to quiet and the backpressure is exactly as you explained. Took it for a ride and it would'nt go. I had all the bolts tightened down and the pressure actually pushed the tubes back 3/8 of an inch I could tell that because I saw where the never-seize line was from installation.
I have a side pipes with reverse flow side pipes. I have just installed 427 bb engine, and to be honest I am some what disapointed with its performance !
Looks like these reverse flow pipes may be the issue!
Cheers
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Melting Slicks
Joined: May 2005
Posts: 2,209
Likes: 12
From: Montgomery Alabama
Cruise-In VII Veteran
St. Jude Donor '06
I love the STS baffles in my Hooker side pipes.
They are a bit raspy (tinny) at idle, but SCREAM! when I give it WOT. I can talk at a normal level while cruising.
I also shaved about 30# of weight off the car from the heavily restricted Hooker glass pack inserts (the center was barely over 1" in diameter).
They are a bit raspy (tinny) at idle, but SCREAM! when I give it WOT. I can talk at a normal level while cruising.
I also shaved about 30# of weight off the car from the heavily restricted Hooker glass pack inserts (the center was barely over 1" in diameter).
Team Owner
Joined: May 2001
Posts: 87,409
Likes: 1,595
From: Western NY
Back in the late 70s, I had the Hooker sidepipes on my Pontiac T/A. I first had the glass-pack inserts in, and yes, they were LOUD. You could hear me coming from 2 blocks away. Later on, I tried the reverse-flow inserts. I agree with all of the above comments, in that they were more restrictive, but I could at least hear myself think.....
Racer
Joined: Jan 2010
Posts: 367
Likes: 1
From: Christchurch Canterbury
Pulled the trigger and ordered some maxi flow hookers from summit.
#21046HKR
I tried to order some sweet thunder inserts, but never got any reply....
( I often find US companys that are not interested in international orders)
I did get a prompt responce from STS, but there price and freight options made the hookers about half the price.....
So out come the reverse flow baffles and hopefully I will not attract too much interest from the cops ...... and hope to find that "missing" hp!!
#21046HKR
I tried to order some sweet thunder inserts, but never got any reply....
( I often find US companys that are not interested in international orders)
I did get a prompt responce from STS, but there price and freight options made the hookers about half the price.....
So out come the reverse flow baffles and hopefully I will not attract too much interest from the cops ...... and hope to find that "missing" hp!!
Drifting
Joined: Jan 2012
Posts: 1,908
Likes: 129
From: Fredericksburg Virginia
Those MaxFlow Hookers look pretty cool...I REALLY need to do something about my rusted-out inserts, but haven't been able to pull the trigger on STS Baffles. Wish they weren't so expensive.
Does anyone else have the MaxiFlow inserts? Pretty safe to say they're less restrictive than the Glasspacks, right?
Does anyone else have the MaxiFlow inserts? Pretty safe to say they're less restrictive than the Glasspacks, right?
Pro
Joined: Jul 2010
Posts: 691
Likes: 25
From: Boynton Beach Florida
The Max Flows were the first inserts I tried and they flow great but the volume with a coupe car was too loud and very DEEP tone. Obviously a lot of the sound and volume will vary depending on your engine compression, cam and overall horsepower.
I put the glass pack inserts in and they brought the volume down but I could tell the flow was sacrificed too so I had a custom set of inserts made but I'm working on the car now so I haven't had a chance to install them and shoot a video. The link in my signature will take you to a video with the Max flow inserts at idle with a few revs which sounded great but under load was a different story for me anyway.
I put the glass pack inserts in and they brought the volume down but I could tell the flow was sacrificed too so I had a custom set of inserts made but I'm working on the car now so I haven't had a chance to install them and shoot a video. The link in my signature will take you to a video with the Max flow inserts at idle with a few revs which sounded great but under load was a different story for me anyway.
Racer
Joined: Jan 2010
Posts: 367
Likes: 1
From: Christchurch Canterbury
The Max Flows were the first inserts I tried and they flow great but the volume with a coupe car was too loud and very DEEP tone. Obviously a lot of the sound and volume will vary depending on your engine compression, cam and overall horsepower.
I put the glass pack inserts in and they brought the volume down but I could tell the flow was sacrificed too so I had a custom set of inserts made but I'm working on the car now so I haven't had a chance to install them and shoot a video. The link in my signature will take you to a video with the Max flow inserts at idle with a few revs which sounded great but under load was a different story for me anyway.
I put the glass pack inserts in and they brought the volume down but I could tell the flow was sacrificed too so I had a custom set of inserts made but I'm working on the car now so I haven't had a chance to install them and shoot a video. The link in my signature will take you to a video with the Max flow inserts at idle with a few revs which sounded great but under load was a different story for me anyway.
The 427 BB feels by the seat of the pants like driving a strong 350 sb, not a modified BB. The previous owner of the engine had run 10's in 1/4 with it.
I have dropped the comp from 13:1 to 10.8:1 and replaced the old iron closed chamber heads with Brodix race rite heads, only other change in the LS6 manifold, in place of the single plane deal.
I know I will have lost some hp's, opinion is it still should go ok.......
We shall see shortly i guess
Le Mans Master
Joined: Apr 2007
Posts: 7,353
Likes: 72
From: Graceland in a Not Correctly Restored Stingray
Had 'glasspacks, sold reverse flows without every trying them, and planning on MaxFlows this time around. Sweet Thunder would be my second choice. STS are a bit tinny to my ear. Wondering how cones and MaxFlows would sound...
