Will Emissions pass mot without cat?

2nd cat only properly gets hot enough on a motorway cruise when the lean burn mode kicks in, or if you absolutely flog it at low speeds. The primary cat gets fresh hot exhaust from the head, which is where the exhaust is hottest and the cat works best.
 
You mean 2nd cat alone isn't enough?
If you want the 4 2 1 manifold and a performance exhaust you're going to have to fit a racing cat as soon after the manifold as possible to keep the emissions legal. Doing this usually means a custom built system as the o2 sensors need refitting also. Lots swap exhaust systems back just for the mot but I couldn't be bothered doing that to be honest.
 
Mid mounted cats are fine as long as a) they are of decent quality & density e.g. 200cpi and b) the car is properly mapped.
 
That's a shame, my mate recommended taking off the cat, bashing the hell out of the honeycomb so it fell out then refitting hoping it would get thru emissions and save cost of me cat.
 
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