fredtoast

I'm getting a custom exhaust, and I'm trying to decide on what I should use to keep it quiet. The glasspack mufflers are a lot cheaper than resonators so I was wondering what are the advantages of a resonator. I know resonators don't have any packing in them, and they deaden the sound in a different way than mufflers. Do they make the exhaust a lot quieter than glasspacks? Are resonators significantly lighter than glasspacks? Do they give the exhaust a different tone?

Honda Hick

I just threw a $15 glasspack on mine. It didn't really make it quiter but it got rid of the much of the ricer, high pitched sound. Its deeper now.

GregR

Not sure about the sound, but a resonator would have a different tuning effect on the engine than a glasspack would (assuming they're in the same location). Normally, a resonator is placed quite far upstream - slightly after the cat - and it's used to terminate the collector pipe length (which has an effect on engine tuning). I don't think glasspack's are placed that far up though, but I could be wrong. If they are, then a glasspack would make the collector length somewhat longer than a resonator, which if I recall correctly tends to provide a little more low-end torque. Minor effects, though.

emr88

Fredtoast, we must be on the same path, because I've been thinking about this too. The Dynomax Thrush Glasspack http://www.dynomax.com/documents/thrushglass.pdf
Appears to made similar to the Magnaflow Roundbody muffler/resonator in that both have perforated straight thru construction. However what is the internal diameter of the glasspack versus the resonator? Judging from looks, the Magnaflow appears to be constructed better, but does it really flow that much better to justify the cost over the Dynomax? If
My guess is that the Magnaflow has better, longer lasting packing material and it's constructed better but the flow rates are probably comparable *if internal diameters are similar* as both use perforated cores. Louvered cores are much more restrictive.

Try to contact the manufacturers, maybe they will provide flow rates?




[Modified by emr88, 8:09 AM 3/15/2003]

fredtoast

Thanks for the info. Yes I am talking about using a glasspack right after the cat in place of a resonator or maybe even in place of the cat. Any more opinions?


[Modified by fredtoast, 8:33 AM 3/17/2003]

Bailhatch

I helped a friend do an exhaust on his prelude w/ h22 swap. We had a pacesetter exhaust so we cut off the rear muffler (which of course was rattling) and welded on a cheap uni-muff. it was loud so we put a 24" $20 glass pack just after the cat. it sounded great for being built out of the WORST aftermarket exhaust ever. Hey it had mandrel bent pipes and was 2.5". cheap setup that works and costs little. glasspacks tend to 'burn in' as the fibers inside break off and get shot out. so they get a little louder as they age, but they are CHEAP.

BROOD

A flow through Magnaflow resonator would be a better choice over a traditional glass pack muffler. The design of the glass packs (punched louvers) is very restrictive compared to the preforated core design of a Magnaflow resonator.

Basically you have a comparison between old muscle car exhaust technology (louvers core) and modern exhaust technology (perforated core), which one do you think flows better???

emr88

But not all glasspacks have louvered cores, like the Dynomax Thrush example I posted above. It looks similar in design to the Magnaflow. Unless the internal core diameter is a lot smaller than the Magnaflow, it should flow comparably right?



[Modified by emr88, 9:23 AM 3/17/2003]

BROOD

Your right, you want a perforated core style. Steer clear of the louvered cores.