1nasty86

iTrader: (63)

ok. so i have heard a well build 4 body needs more than a 3' single exhaust. i was looking at the mufflex catback but would 3.5' be too much for a h/c/i 5.3 with a 100-150 shot? mufflex is the only company i know that makes exhaust for a f-body that is available in 3.5 and 4'. but if the magnaflow 3' exhaust wouldnt choke my motor im going to go with it because it is alot less. and i believe the 4' would be way too big for a 5.3 or 5.7. maybe for a 402 or larger build. i know you need backpressure so would a set of 1 3/4 stainless works headers with a 3' y pipe into a 3.5 single mufflex exhaust work for my motor?

LS1BLKSS

iTrader: (36)

god damn thats a hugeeeeeeee pipe 3'! most people will go 3" lol just messin with you 3" will be fine

1nasty86

iTrader: (63)

im just wanting to go the best route possible. i seen a vid on a 383 that made 460rwhp and he was told his 3' maganflow exhaust was too small.

mastercoryd

iTrader: (3)

get a 3.5" to 4" cutout with a flowmaster merge and then run a 3" magnaflow catback

1nasty86

iTrader: (63)

so the 3.5 mufflex would be too big?

LS1crazy01

iTrader: (14)

If I had to pick one of those I would say the 3.5 inch but if it where me I would go with 3inch true duals with an X pipe and what ever mufflers you wanted and call it a day.

1nasty86

iTrader: (63)

i was thinking the 3.5 also.. im just concerned about backpressure..

LS1crazy01

iTrader: (14)

Then stick with the 3" if your that worried. I mean that will be enough for you. I've seen plenty of people pushing 3" over the 400hp all day long. How much power do you intend on having??

1nasty86

iTrader: (63)

right at 400 on motor then spraying a 100-150

Engine_HP

iTrader: (1)

^^^ this

mastercoryd

iTrader: (3)

you dont need to worry about back pressure on these cars dude, but 3" is fine just use the cutout to get your horse or true duals like the other guy side is good option, just hard to fit sometimes

domestic disturbance

iTrader: (35)

3" should def be fine... I made 400rwhp 405 torque on motor and 505hp and 545tq on spray in a cam only bolt on ls1 with 3" exhaust, cutout, stock catback!!!!

mastercoryd

iTrader: (3)

see, the catback doesnt matter aslong as u have a cutout and even though his numbers are great if he had done a bigger cutout he may have even gained more horse power but its all about your goals a nice magnaflow or hooker catback and a cutout should do fine, if u have a large cam and heads and really looking to squeeze those numbers out u might want to upgrade to a 3.5 or 4" cutout or dual cut outs but i dont see a need for a 4" exhaust all the way back

01ssreda4

iTrader: (96)

you dont "need" backpressure for anything. Its a myth created by idiots Go with the biggest exhaust you can fit. Bigger wont hurt you, smaller may.........

Engine_HP

iTrader: (1)

how much did u gain from closed to open cutout ? just curious...