1slow67

Don't get the short glasspacks. I have 1 on my 67 and it sounds decent at idle, but once you start going it sounds like a Honda to me. I'm going with Magnaflow once I redo my exhaust.

andrewmp6

After so long the fiberglass will burn out of them.Spintech is the only normal muffler that's even close to the sound.

4reboy

I have Blue Streak glasspacks on my car, but it came like that when I bought it. Sounds good to me, but I don't really know anything else.

Does anybody elses car leave black deposits on the ground during warm up? I know our cars run rich at startup because of the choke, but the parking garage I park in is full of exhaust marks in many different spaces lol. I wonder if it's because of my old rusty pipes, the glasspacks, my idle mixture, or just the concrete floor accepts stains way to easily lol

1slow67

That is just carbon buildup in the pipes that gets pushed out when you start the engine. Mine used to do it every time I started it.

Carlos Pineiro

Glasspack lengths and core diameters vary. Sound and performance balance is a personal choice.

Flow can be restricted even in straight through mufflers, as Norm pointed out, but as they say, size does matter.

CP

tx65coupe

Any straight through muffler like Magnaflow, Dynomax Ultraflo, or even a glasspack will flow better than a chambered muffler like Flowmaster. Actually, Flowmaster is one of the worst for performance.

tx65coupe

I have those and think they sound great! They also have a lifetime warranty.

http://www.youtube.com/watch?v=LXk_MVV7V0g

Norm Peterson

Hooker also made an oval can muffler with center/offset stubs that runs straight between them internally. Supposedly it's one of the better flowing mufflers, and I've got a pair of them on the '79 Malibu.

I hope they still make it.


Norm

JMD

I have Smithy's in my 55 Lincoln, Mitch has them in his 64 Falcon, and they just flat *** sound good.

They are not too damn loud, and the longer ones not sharp like other glasspacks CAN be.

tx65coupe

I know what you mean. When I first got my 65 running back in high school, it still had the 200 I6. We put a short glass pack on it and it sounded decent at idle and low speeds, but as the RPMs increased, it sounded kinda bad. It was because it of the I6. It actually sounded very much like my friend's early 70's VW Bug that had super beetle exhaust on it.

I swapped the glasspack out for a single in dual out transverse muffler for a Firebird, I think it was a Dynomax or similar turbo style muffler. It sounded good for a 6 cylinder after that.

On a V8 the short glasspacks are too raspy.