Ive got a 94 fleetwood with a 5.7L I wanna put an exhuast on it like my older caddy. I just went with flowmasters on my other FWD fleetwood and it sounded good but this 94 is RWD so i wanna run new pipes all the way to the exhaust manifold. What are glass packs or glass backs exhaust? I heard that they cause a restriction resulting in less power but they sound really good. Maybe im thinking about cat backs? anyone know about different exhuast types?

 

I’m astounded that after 50 views you have no response. Having come from the f-body world initially, then into the w-body Regal, I’ve been slowly moving into less technical forums. It’s sad really, but I digress…

A Glasspack is a straight through cylinder style “muffler” that has a perforated tube surrounded with packed fiberglass as a sound deadener. Because it’s basically a tube, it’s loud and has very low back pressure. As an aside, Glasspack is a trademark of the Cherry Bomb company. Glasspack has however become a generic name for any tubular fiberglass packed muffler, i.e. the common usage of Kleenex and Q-Tips. You also mention a cat-back exhaust. Cat-back implies that the exhaust pipes are completely replaced from the catalytic converter(s) back. I’m not familiar with the layout of the Fleetwood exhaust, so I’m not sure if it’s true duals, or a single into dual mufflers, or single into single with dual outlet muffler, etc…

I’ve always thought that a Glasspack was a bit much. They’re cool on muscle cars, but for anything else, I’d stick with Flowmaster. I seem to recall that the 95 Fleetwood had an LT1, but the 94 was the TBI 350 right? I’m not sure what it sounds like, but IMO an LT1 with a Flowmaster sounds very nice, albeit loud if you go with a lower end model. I had (I believe) a 50 series Flowmaster on my 1997 Z28 and could ride through the parking lot in 1st gear and set off car alarms.