o.k. boy's & girl's , i'm starting another header project . i need to know the thread size for the O2 sensor . i have hedman headers # 68478 & Y pipe # 17478 . no O2 bung , so i will have to weld one on . anyone know the size ? i would like to have all parts ready before start this project . thanks .

 

Summit racing sells those, or at least you should be able to find out the size/thread of them. I've put in a few, but either get something more expensive than summit brand or be sure to smother some antisieze on them.

 

thanks for the lead 82z . i checked summit site , seems like they are 18mm x 1.5 . i was not sure if they were metric or SAE . now i know , thanks again .

 

thanks, I needed to know that too, I'm not going to pay $12 for a nut when I can get one at lowes for $.30!!

 

well you won't find one at lowes , largest i could find there was a 12mm . same at several parts stores . i finally found one at a specialty nut & bolt place . cost $2.75 , 10 bux less and no shipping , did take my time & gas . use your phone or you will run around all over town . not a common size . good luck .

 

I found the out about lowes last night(I work there) I figured I would have to go to a specialized hardware store, but it's still way cheaper than $10-$12 for a stupid fitting.