Your favorite muffler performance wise.

[exilous]

OK caus what I'm going to be running on my truck is true duels my friend has a bending machine so I can bend whatever I want. And I heard my dad mention something about Tri-y headers a long time ago being real good and stuff so I think I would like those. They say they are for mid range power which is what I would need in my truck. Those ones you just posted aren't tuned though. SO I should stick with the ones from the doug thorley website then?

[eventhorizon66]

I really don't think there is such a thing as an off-the-shelf "tuned" header for a SBC.  And if it is "tuned", for what rpm range and on what engine?  Header tuning can only take place on a dyno for a specific engine and it is very involved.  Let the professional racers worry with that.  Any good off the shelf header will work for a SBC in a street application.

[exilous]

Ok, cause i've seen some that say tuned and some that say they arent, i just assumed tuned headers were matched tube lengths for opposing sides of the engine and stuff.

[Captkaos]

The TH-367Y is a mid-length design with a y-pipe.  Chris is using a set of these on his Jimmy project as it will have a single exhaust and he had some issues with the fit.

I am attibuting my fit issues with the fact that I think they sell the mid/Y setup like on my Blazer for all Blazers and didn't test fit them on 4x2 Jimmy/Blazers like mine is.

Originally Doug Thorley Headers was the Original company ran by Doug Thorley and family.  A few years back he divorced and she retained the rights to "thorley" but couldn't use his name, so...
Dougs headers was created which was ran buy Doug Thorley and they are good headers.  He sold his business to Petronix but I believe he is still involved with the company.
Since then, Jardine performance bought Thorley and somehow obtained the full name again.  Summit Industires (not Summit Racing ) own Jardine and Doug Thorley, still they are good headers.

As far as "tuned" headers, it really depends on how they are using the term.  Generally Tuned are equal length long tube headers with the same length tubes for all pipes.

[exilous]

Ok, so Doug Headers, Thorley Headers, and Doug Thorley Headers, are technically all the same company and all good headers?

[Captkaos]

No, Thorley no longer exist it became Doug Thorley Headers, they are 2 different companies.

Dougs Headers are owned by Petronix
Doug Thorely Headers are owned by Summit Industries

[84chevysilverado]

what do u guys think bout purple hornies on a 305 with long tube headers? are purple hornies any good

[eventhorizon66]

From what I hear, purple hornies or any glass pack, for that matter, sound awesome initially, but deteriorate quickly and begin to sound like crap.  From a performance standpoint, straight-through turbo style mufflers are better.

[exilous]

my buddy had a set of thrush glasspacks and he loved them, they lasted about a year and a half before they started to sound a little fuzzy...by the time 2 years rolled around he was replacing them.

[SUX2BU99]

^ Sounds-about right for glasspacks. I have Dynomax Ultra-flows on mine, which are a turbo-shape (oval case) flow-through design. I've always know turbo style mufflers to be the ones that redirect flow internally with the use of internal tubes and baffles (if you're lucky) so they aren't as direct as a flow-through mufflers. Why a turbo-style is called what it is, I'm not sure. Nothing 'turbo' about it I don't think  lol   What makes glasspacks different from something like the Ultra-flows are glasspacks use louvres that protrude a little into the exhaust stream to 'scoop' the airflow into them. This is more effective than the perforated tube inside the Ultra-flows for sound absorption, but are worse for air flow. That and cheaper glasspacks tend to bottleneck the pipe at the inlet and outlets. And them some glasspacks use two small internal tubes in parallel to route the air through them. This is also a restriction as it's less cross sectional area through the two small pipes vs. one larger pipe. If you want a 'classic' rap-rap-rap sounds, glasspacks are good for that. Through high school in the early 90's these trucks, pretty much bone stock but with 2" duals and glasspacks were the norm around the parking lot

[nogomoto]

I'm cheap. I have an incredible sound for under $200.

I did some lookin around and found an old set of unused longtubes for next to nothing. Did some more lookin and callin and found 2 sticks of 2.5" aluminized pipe for $35 out of an automotive repair shop that had overstock. I talked to several people to get opinions on what mufflers to run and I found that TWO WELDED THRUSH mufflers can be shipped to your door for around $65 and they sound deeper, a lil more quiet and with a smoother tone than the flowmasters that were on it. I got those for free by trading a tranny core that was given to me. I clamped on dumps instead of running the tailpipes that I had just because they were ugly as all get out. The collectors that I got were around $35 with the gaskets and it was less than $100 for all of the install parts, drinks, and food, with a very relaxed day in the garage.

If I wanted the tail pipes back on, I have enough pipe and hangers left over to do it. Thrush is better and much cheaper than Flowmaster IMHO.