Cat fooler related Q's

So I have been wondering a bit; On the version of the M54B30 (M54's in general) that we get here locally comes with two pairs of cats on in the exhaust manifold and a pair in the pipes after the manifold. But the manifold on ours only has two lambda probes, one in each 3 cylinder part of the manifold after the first set of cats, and nothing else further down.
Like this:

So if I am not mistaken you only need cat foolers or mini cats (whatever you would like to call them) if you have pre and most cats sensors, like in this one:

So I should be able to get away without cat foolers if I only have on set of lambdas, or am I mistaken?

Thanks for any inputs guys.

If you truly only have one set of O2 sensors, then I say rock on! Don't worry about the foolers and don't worry about cats. Put some headers on!

Yup only one set, as my headers look like those in the first pic I posted, and they only have one set in and there is nothing more in the exhaust as I have removed the exhaust before and I think I would have remembered if there was sensors in it. The other good thing is that there is no emissions testing here,

Originally Posted by Sankekur

The other good thing is that there is no emissions testing here,

exactly why your car doesnt have a set of post cat 02 sensors

Originally Posted by drumbum624

exactly why your car doesnt have a set of post cat 02 sensors

Well it does have post cat sensors, thing is it just doesn't have pre cat sensors, I am would assume it need that layout of before and after sensors to do cat efficiency tests, but yes cat efficiency does not need to be check cause emissions are not important.