So I got my summit glasspack yesterday and they seem um... hollow. Isn't there supposed to be fiberglass stuffed in there? Or is it just the baffles?

its in the baffles, behind them to be exact... thats what you want.. hollow and straight through... FLOOOOOOOW

Wow, this suckers gonna be loud.

yes it will but, not as bad as a pipe.

You did know it would be loud right?

that mother' is gonna scream when you get on it!

a stroker engine with those "mufflers"?!?!?!? it will be loud and wicked sounding.

you should post a sound clip if you get a chance

Well I expected loud, but I mean dang. There's nothing there Guess we'll find out soon enough.

that's not quite the greatest for straight through.
those baffles are horrible at making things flow well as they not only make the ID of the muffler smaller just because they stick in there but also when the gasses hit the baffles it pushes the exhuast around creating turbulance and so forth.
I'm asleep kinda so can't find the words I'm looking for

i was meaning its a hell of a lot better than the standard baffled mufflers..

yes it will flow..

no bends to slow the exhaust gas travel (quickest way from A to B is a straight line)

maybe not bends
but bends aren't the only way to slow the exhuast down.

those nice louvers do a good job of it also

Sorry, but those louvered core glasspacks don't flow worth a crap. In fact they suck. I agree, a straight-thru muffler is the best flowing, but you want a perforated tube core, not a louvered core. Those louvers sticking down into the tube really obstruct the gas flow.

Look at a Magnaflow. Perforated straight tube from the inlet to the outlet. Flow great. And surprisingly, aren't terribly loud.

I have a magnaflow crossflow model on my IROC. When it was brand new it was actually real quiet. Now that it's broken-in, it's a lot louder. At WOT, it's actually quite loud. But at idle and cruise, it's not bad, quieter than a flowmaster and without that nasty interior drone.