Lambda Sensor Boss, What size?

[billy187]

I have just changed the elbow on my car to one of those tomie 3" elbows but noticed there was no boss for the lambda sensor to screw into, anyone know what size i need and where i can get one from quickly?

 

[Sunny-D]

I had trouble finding one for a janspeed elbow, in the end i brought a plug like this and had it drilled and tapped.
http://cgi.ebay.co.uk/M18-X-1-5-Lam...arts_Vehicles_CarParts_SM?hash=item4a9b1679d4