STS Baffles 3" or 4"?
Thread Starter
Drifting
Joined: Jun 2008
Posts: 1,565
Likes: 111
STS Baffles 3" or 4"?
Hey guys, I'm looking to upgrade the side pipes on my '69. I currently have the factory side pipe covers. Has anyone tried the 3" STS baffles in a 3" pipe under the stock covers? If so, how do you like it? I've got a 427 BBC with Edelbrock heads so I'm probably in the 450-475hp range. My other option would be to go to a 4" side pipe and leave the covers off.
Thread Starter
Drifting
Joined: Jun 2008
Posts: 1,565
Likes: 111
Drifting
Joined: May 2005
Posts: 1,968
Likes: 44
From: East TN
From what I've seen others do, you will have to add a 1" spacer to bring the covers out a bit to fit a 3" pipe under the covers and then find inserts for the 3" pipes. Also, the 3" pipes will need tips that match up with the covers. Nice undercarriage 
Maybe some else that has done it will chime in.
I went from stock '69 style to 4" SS Hookers with Max Flow inserts on my '80.
Maybe some else that has done it will chime in.
I went from stock '69 style to 4" SS Hookers with Max Flow inserts on my '80.
Thread Starter
Drifting
Joined: Jun 2008
Posts: 1,565
Likes: 111
From what I've seen others do, you will have to add a 1" spacer to bring the covers out a bit to fit a 3" pipe under the covers and then find inserts for the 3" pipes. Also, the 3" pipes will need tips that match up with the covers. Nice undercarriage
Maybe some else that has done it will chime in.
I went from stock '69 style to 4" SS Hookers with Max Flow inserts on my '80.
Maybe some else that has done it will chime in.
I went from stock '69 style to 4" SS Hookers with Max Flow inserts on my '80.
Thread Starter
Drifting
Joined: Jun 2008
Posts: 1,565
Likes: 111
Just heard back from Sweet Thunder. Another option for me is to run their 3" OD mid-year pipes with 2.5" baffles (#MY4015). These should bolt up to the stock frame mount and the turn down will exit in the proper position.
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Safety Car
Joined: Oct 2000
Posts: 4,080
Likes: 565
From: Allen TX
Neil, are you trying to gain more power/increased sound, or what?
In my '69 BB car I had (454 w/ AFR heads, decent hyd roller cam, and Edel Perf AirGap intake), I installed the Hooker SS sidepipes with their inserts. It killed power above 4500rpm. I don't care what Hooker claims, those things are restrictive as all get out... probably worse than what you have on there now. I mean the engine literally hit a brick wall at 4500rpm...and it was tuned to turn 6300 easy and made power up there.
I yanked the pipes off and ran open for a few days just to make sure the car would run well with side pipes (it did!). Obviously that was too loud for everyone, including me, so I got the JCL STS bafflers (and I cut off the "caps" on them to allow for more airflow) and they were an amazing improvement. Car made 435rwhp/465rwtq with a 5-speed trans (probably 520-530 crank hp).
I don't know how the Sweet Thunder inserts you have now compare to the STS baffles, but I _guarantee_ you they have to be as good as the Hooker stuff... at least for a modded engine like yours.
In my '69 BB car I had (454 w/ AFR heads, decent hyd roller cam, and Edel Perf AirGap intake), I installed the Hooker SS sidepipes with their inserts. It killed power above 4500rpm. I don't care what Hooker claims, those things are restrictive as all get out... probably worse than what you have on there now. I mean the engine literally hit a brick wall at 4500rpm...and it was tuned to turn 6300 easy and made power up there.
I yanked the pipes off and ran open for a few days just to make sure the car would run well with side pipes (it did!). Obviously that was too loud for everyone, including me, so I got the JCL STS bafflers (and I cut off the "caps" on them to allow for more airflow) and they were an amazing improvement. Car made 435rwhp/465rwtq with a 5-speed trans (probably 520-530 crank hp).
I don't know how the Sweet Thunder inserts you have now compare to the STS baffles, but I _guarantee_ you they have to be as good as the Hooker stuff... at least for a modded engine like yours.
Thread Starter
Drifting
Joined: Jun 2008
Posts: 1,565
Likes: 111
Neil, are you trying to gain more power/increased sound, or what?
In my '69 BB car I had (454 w/ AFR heads, decent hyd roller cam, and Edel Perf AirGap intake), I installed the Hooker SS sidepipes with their inserts. It killed power above 4500rpm. I don't care what Hooker claims, those things are restrictive as all get out... probably worse than what you have on there now. I mean the engine literally hit a brick wall at 4500rpm...and it was tuned to turn 6300 easy and made power up there.
I don't know how the Sweet Thunder inserts you have now compare to the STS baffles, but I _guarantee_ you they have to be as good as the Hooker stuff... at least for a modded engine like yours.
In my '69 BB car I had (454 w/ AFR heads, decent hyd roller cam, and Edel Perf AirGap intake), I installed the Hooker SS sidepipes with their inserts. It killed power above 4500rpm. I don't care what Hooker claims, those things are restrictive as all get out... probably worse than what you have on there now. I mean the engine literally hit a brick wall at 4500rpm...and it was tuned to turn 6300 easy and made power up there.
I don't know how the Sweet Thunder inserts you have now compare to the STS baffles, but I _guarantee_ you they have to be as good as the Hooker stuff... at least for a modded engine like yours.
Safety Car
Joined: Oct 2000
Posts: 4,080
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From: Allen TX
Mine lays down around 4,500-5,000rpm too. My current mufflers are '69 factory-style reverse flow mufflers. The 3" headpipes neck down all the way to 1 7/8" at the muffler inlet. I know there's big power if I swap out the muffler. I'm not afraid of a little noise to get it, but I'd really like to keep my stock covers if possible.
Didn't realize the stock setup transitions down to 1 7/8"... yeah, that's not great for performance.
Drifting
Joined: May 2005
Posts: 1,968
Likes: 44
From: East TN
My old setup had Hedman Headers 1 5/8" to 3" collectors, 2 1/4" connector pipe into 2" SweetThunder sidepipe mufflers.
What I have now is 1 7/8" Hookers into 4" collector with 2 1/2" Hooker Max Flow baffles. The engine (385 stroker, about 500 hp) is no longer being choked which you could feel with the old system. I thought about going with the STS baffles, but I believe they have a tinny tone to them and wanted a nice low deep tone that the Max Flows produce.
Hooker has 3 baffles;
Reverse Flow = very restrictive, lowest noise level
Glass Pack = some restriction, mid level performance and noise
Maximum Flow = best performance, highest noise level
Here's the inside of the Max Flow, 2 1/2" straight through.
Last edited by MIKE80; Nov 18, 2014 at 10:00 AM.
Pro
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From: tx