Thanks for the link Ray it looks interesting. Just in the process of registering so I can see the pictures. If it's too much hassle I'll keep swapping between the termi's & standard depending on track noise levels.
The reason for looking into this is that my Termi is showing signs of overheating after only 4500 miles & I was assuming that it was caused by using the db killers on quiet trackdays also db killers should be called hp killers as a restricted 125 could pass me with them in.
The main reason for the de-cat was because I wasn't sure what the results of having a rich mixture was likely to be. I know a weak mixture destroys cats which is the reason for lambda sensor but didn't want a rich mixture to block the cat.