i seen some 2.5 in by 2.5 in flowmaster 10 series mufflers for sale pretty cheap. I know that flowmaaster isnt really supported on this board but anyone know what they sound like true dualed with an x pipe and high flow cats? im looking for something pretty loud, but if i cant get the sound i want the borla pro xs mufflers have a really deep sound i like. i also like dynomax bullets as well. oh 1 question i have a 99 f150 and since im replacing all 4 cats with two high flows do i have to mount the o2 sensors 1 in front and 1 behind each cat. im trying to keep away from a cel. i dont have a custom tune yet and probably wont get one in the future due to i have a edge evo and i heard they wasnt converting those anymore to gryphons

 

^ It will sound like a loud flowmaster. I really don't know how else to describe it. They all sound about the same. The 10's have less of a deep flowmaster tone IMO.

Leave your primary o2 sensors alone! The secondaries need to be at the end of your high flow cats.

 

so if i remover the four cats and replace them with two high flows i leave the primary o2 sensors infront of the cats closer to the exhaust manifolds and the secondary o2 sensors should be after the high flow cats then?

 

Now you got it!

 

Here was my setup with 2 Flowsound single chamber mufflers. They are essentially a copy of the Flowmaster 10 series. Ebay X-pipe, high flow cats, the rest is in the description. This setup droned pretty good at like 1800 RPM's FYI. I only had this setup on my truck for a week, I had the exhaust completely redone b/c this setup was leaking at the header collector point. It sounded nice, but I like my current Magnaflow true dual setup a lot more.

http://www.youtube.com/watch?v=-_5SFHb09i4

 

I currently have an 05 F150 with a 3 in 10 series dumped under my bed. It sound ok. It has a good rumble at idle, but seems too raspy for me under full throttle. I should have kept the super 40 dumped

 

NacsMXer: very nice truck, I like all the mods and its a very spotless truck!

 

I would suggest bullets or magnapacks if your going to do a true dual system. If you want to spend more and sound the best, go with Borla Xr1s or S-types

 

I think the flowmaster 10 series is LOUD...

 

my truck has no cats, and a MIL eliminator o2 that keeps it from throwing a code, has no issues whatsoever, although mine is a single exit with one 40 series flowmaster. Sounds absolutely perfect, although it is single exit.