I Need Some General Header/Exhaust info
 

so my headers will probably be here next week and im trying to make sure i have everything towards the install. i figured i would band clamp some glasspacks onto the collectors until i run my full exhaust. are mufflers measured in I.D. or O.D? its a 3inch collector so what size inlet should i use on the muffler? i want to make sure i get the right band clamps.

my other concern is a tune. will i be able to drive it home from where ill be working on it without a tune? or is that a no-no?
im just trying to be prepared. its better to be safe than sorry

for the overall (full exhaust) setup i cant decide whether to neck it down to 2 1/2inch with reducers before the muffler. i figure the headers will make it louder,atleast on the top end,so with the right muffler could i achieve a growl and volume level similar to my 2OTL?

i just figured somebody might know something i didnt-haha . im mainly worried about driving it without a tune.i can trial and error the rest i suppose. if i keep the rpms down when driving without the tune should i be alright?

you dont have to get a tune when just installing headers. you can if you want to get the most power out of them but ive been running mine for a year without a tune. just get 3 inch diameter mufflers and they should clamp into the headers. i used 3 inch mosoro spiral flows on mine for a couple weeks until i got my duals run.

if you already got a 2otl exhaust why dont you just buy an offroad y and reuse the catback?

my 2otl is about 10yrs old now. it came on the car when i bought it so i just wanted to replace it since its pretty rusty. i just figured i might as well run true duals. thanks for letting me know im alright without a tune for awhile.i wasnt sure