Hooker header's and flowmaster
 

How would my exhaust sound with Hooker header's, orp, with out cat's, and flowmaster American thunder cat back? What rwhp can I expect with the hooker header's? I all ready have the flowmaser on. 99 Trans Am m6

i hear the flowmaster w/ no cats has alot of drone other than that iw ill be loud :)

sound ok, flow like crap...........

imo, with long tubes and an off road y pipe that flowmaster catback will sound really good. watch out for the 2k rpm drone, its giogn to sound very loud inside the car but outside will tell the story, just a reason to upgrade the sound system inside :) if you have the cross flow muffler 80 series your flow is going to hurt the performance of those long buts but you will still get a gain with the lt's

honestly whats the big deal about flow?!?! at most tracks you dont need any kind of muffling devices so why not run a cut out, which does flow better than a GMMG or comparable exhaust and for hundreds of dollars less. The set up you are looking at will sound good. there is a reason why flowmaster mufflers are the best selling muffler and catbacks on the market, (mostly cause of mustangs but still), sound and you do get some performance whats not to like? enjoy dude, i dont know forsure how much hp you are looking at only a dyno and track times would tell that story for you. if i were you id enjoy that drone at 2k rpms just to piss soccer mom in her suv off when she is behind you. good luck
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