87 STANG

Has anyone ever used these, they are supposed to be a little louder then the regular 40 series but not as loud as the single chambers.

Tims 88GT

They are on my dads f-250 they sound great.

OnyxCobra

I dont think they come in catback kits do they? I didnt see em when i bought mine. If my car was any louder inside i would kill myself... anyone wanna trade their 50 series for mine?

RawGtPower

Get slp loudmouths. Talk about loud exhaust. But i just love the sound.

87 STANG

I have seen them in the jegs website, where do you get the pro chamber american thunders.

Tims 88GT

super 40's used to come in old american thunder cat back kits, but now they use the delta 40's

OnyxCobra

the Pro Chamber is a MAC midpipe, the American Thunder is the catback

mtx11

i called jegs when i ordered my american cat back system and they asked me if i want it loud or LOUD . and the american thunder is the oudest cat back . the other delta series or something like that one use the super 40's but is 329 dollars

Steeda1716

Flows are not the loudest catback...

Ecstasy

slp is the loudest catback, what i was wondering is which midpipe is the best the mac pro champer? they say about it keeping power past the 3,000 rpm range and is it better for deep & loud? i dunno which aftermarket mid-pipe i have now i just know its o/r 2.5". i have flows on there now and my cars loud but i still want it deeper and louder.