TerryConverse

Hello,
Try Street and Performance, (Arkansas) they have a set with 1 3/4" primary and 3" collector. I believe you will need a custom collector between the headers and Sweet Thunder "original sound" chambered side exhaust.

I am updating my 67, still looking for 1 7/8" inch primarys for the LS427.
Good Luck,
Terry

tyoneal

===================================
Terry:

With your 427 what size side pipe are you running? I to have a LS 427.

TY

JBLT1

On my current build I'm using Stainless Works headers and Sweet Thunder sidepipes. My last build used Street and Performance tight tuck headers and Sweet Thunder sidepipes.
http://www.sweet-thunder.com/corvett...pes_63_67.html

TerryConverse

Hello Ty,
I am in the middle of my 540 BB to LS427 conversion, started with paint, so not much of the mechanical stuff is done yet. The car, roadster, is being painted now in Corvette Rally Red, Tuxedo Black 427 hood. I am planning on using the Street and Performance headers with 1 3/4 primary and the 3 inch collector. I decided against needing the 1 7/8 primaries. 3" custom head-pipes to Sweet Thunder 3" chambered mufflers. The video on the Z065 vette was not too loud for me. (is that your car?) I will drag race my vette regularly but primarily it will become a street car. Blueprint Engines LS427 retro package at 625 HP, roll bar, TKO600, original frame, Tom's GM 12-bolt Corvette 3.70 rear end. Slicks at the drags on Torque Thrust II, Factory Style 8" finned knock-offs 15" for street, I have had these for 30 years, cool if you like the original look but still need a wider rim.
Best Regards,
Terry

JBLT1

Terry, The ZO65 was my car, Had to weld in 22" glasspacks on the end of those 3" Sweet Thunder pipes just to quiet it down to the sound in the video. My current build is also a blueprint 427, Using Stainless works headers and 2.5" aluminized sweet thunders. They say the aluminized have a less sharp sound. That car with just the 3" stainless sweet thunders sounded great for about 10 minutes, then it just got enoying, couldn't even hear the radio.
John

TerryConverse

John,
Thank you for connecting the dots for me, it is great to meet you. You did an extraordinary job on Z065. I am really glad to know about the 3" side exhausts noise. My BB 540 was way loud with glass packs down the side. Soon there was no glass left.
I am going to have to figure something out on the LS427 noise, starting with the sweet thunder you suggested + perhaps a baffle in the head-pipe area, like used in boat headers?
Let's be sure to stay in touch on this.
Best Regards,
Terry
tconverse67@msn.com

JBLT1

Sure Terry, anything I can do to help let me know. I think I made every mistake you can on the first build but the end result was well worth all the re-designs. I was told by the sweet thunder guys that the aluminized are much more mellow than the stainless steel. I'm going down to 2.5" to tone it down even more, since my Blueprint 427 dynoed at 632hp, I think I can live with any resulting power loss.
John
jblt1@aol.com

PS; Those baffles don't work(at least the cone shaped ones), tried them.

Joe Inama

I had side mounts on a D & D GS with an LS1. I used Street and Performance LS3 headers and bought Hooker side mufflers, 4 inch elbow and a little tubing bends and your done. Take a look.

SLWRNU

Just my .02 but I bought augers that the sprint car guys use and installed them just before the exits on each sidepipe. Still aggressive sound but much more mellow. Even the wifey doesn't complain while cruising.

93Polo

Did you modify the valve covers in the last pic yourself or buy covers? They look great

JBLT1

Yeah, we built them from real 60s SB valve covers. Working on new set up to completely hide coils for this build.

0BluePrint Engines

Hey Terry and John,
This is Andrew from BluePrint Engines, it is awesome that you both have one of our BluePrint LS427's going into your cars. Please keep us updated on your projects and we would love to feature them on our website through the build process, if you have any questions on the engine please let me know and I would be glad to help.
Thanks,
Andrew Obermeier
Product Specialist
andrew@blueprintengines.com

JBLT1

Hi Andrew, Can't wait to fire this badboy up. The only thing I would wish for with this package would be the option to get a C6 corvette gas pedal instead of the camaro one that comes with it. I know from my last build that an 07 vette pedal fits perfect in these midyear vettes. I will be glad to keep you up to date on the build however.
John

looks like it belongs

JBLT1

Thanks for the tip, will have to check those out.

00fxd

I have the STS baffles in my 4" Hooker side tubes, My 6.0L is in stock form so it is under 400hp but I think they are the answer.

mikey

I've got the hooker max flo in my side pipes.. had sts baffles before the LS swap. I'm happy. Makes some noise though.. might have a dyno video in a week or two to post.

FastEddy

Hooker max flo's They are way LOUD.....

TerryConverse

Hey Fast Eddy,
Looks and sounds great, but a bit too loud for my next engine adventure. Good thing the cops wern't close. That must have been a blast.

I did find a set of Car Chemistry 3" x 3 disk baffles I think I will try in the 3" head-pipes before the Sweet Thunder 3" chambered mufflers.

I am new to Corvette Forum, how did you attach that video to your reply?
Regards,
Terry

FastEddy

Hey terry....I had the highest flowing sweet thunders on the car before the hookers... wasn't much quieter except maybe, maybe, at idle or low speeds - those things are loud too. Pretty much the same exact design inside.

I'm dying to hear someone who has the screw/auger type inserts, to see what they sound like. I need as little restriction as possible - need all the help I can get with only 355ci.

Just copy and pasted the address from the address bar from youtube, directly in with this text. if you want to do it from a file on your computer, scroll down to "manage attachments" while you are posting, but most videos are too large to put directly on here, and some pictures even end up too big.

mikey

Eddy,
sounds are going to be different between different motors, but IIRC the augers were not really any louder than the max flows i have now.. the STS baffles were on an old tired 350 carb motor and now it is the LS2. I think the intake on the LS2 adds considerable loudness as well.
I hope to have some dyno results soon and new video, once i get this new intake running.
The max flows are much quieter than the open pipes I ran for a couple months when the LS2 first went in the car!
Sometimes I feel like it's border line too loud, and think about trying reverse flows, but then I go on a hot rod cruise and it's obviously the right exhaust!
as far as power, hooker claims max flows increase power over open headers, probably due to efficiency with some amount of back pressure i'm sure.