the guys i bought my s2000 from welded the whole exhaust together -.- im not sure why. so theres no flanges or bolts from header to cat and cat to exhaust and the welds keep breaking .... and im sick of it.

so im buying an invidia test pipe and invidia cat back

however i still need the flange to weld onto my stock header.

my question is what size piping is the stock header. and can someone like measure like how far from the first o2 sensor their flange is. so i know where to weld it to fix good with my test pipe and catback.

i dont want the flange to far back or in so the mufflers are sticking way out or under the car

if someone can help me out here i'd appreciate it alot