I believe all flanges should be the same between the dohc vtec motors. Dude must of chopped up his header and welded it back wrong causing the exhaust shop to match the new flange position. Personally, I would change out the exhaust, but that's me (I dont' like welds ), or you could get your cat (or test pipe or whatever welded to the exhaust) chopped off and re welded correctly.


As for what header I'm running, I'm running a 99-00 Civic Si Greddy header. It's a pretty decent header (from what I heard and the power I was making when I dynoed), but it only has one o2 opening. I used it as is for a few months, but I converted over to obd1 so I could use one o3 sensor.