I am looking at getting a new Magnaflow muffler for my '99 cavalier z24. I have determined that it will be 2" inlet/outlet, but there are many options to choose from given this criteria. I am wanting to know how the various designs and case sizes affect sound and flow. I am looking for the quietest design from Magnaflow that still allows decent flow. Here are the options:

12224 Oval, absorption-type muffler, 14" case length, 5"x8" height x width

11224 Oval, absorption-type muffler, 14" case length, 4"x9" height x width

11124 Oval, absorption-type muffler, 14" case length, 3.5"x7" height x width

13650 Round, absorption-type muffler, 18" case length, 6" diameter

13214 Oval, 3-chamber XL muffler, 14" case length, 4"x9" height x width

Let me know what you think. Thanks!

magnaflow vs Stock LSJ cobalt ss Muffler...

all the flow as the magnaflow with none of the noise... its been dyno proven.

Truth! Either cobalt SS or dynomax super turbo, same thing, all the quietness of stock, all the flow of open exhaust.

The cobalt lsj muffler flows so well my o2 won't stay heated at low rpms anymore haha. Easy fix but proof positive of better flow.

Zs Z wrote:The cobalt lsj muffler flows so well my o2 won't stay heated at low rpms anymore haha. Easy fix but proof positive of better flow.

hmm did you figure this out with a dtc or a runability concern... i had a o2 code for a while but i figured it was a wiring issue since my extension wire needs to be replaced due it being heat soaked from being ran near the header...

I got DTC for insufficient signal bank 1 sensor 1. Tried replacing the o2 and still the same. In a data log everything is fine as long as my foot is on the gas keeping it hot, let off and the sensor gets really erratic. I can also smell it running rich at idle or stops and it can run rough from time to time.

i'll keep that in mind after my motor rebuild... thanks

i have a thrush welded muffler chambered. sounds like a subaru at low rpms.


whitey