Can I run a single cat at the end of the y pipe or will it bang the floor? Would it even clear the floor?

 

I dont think it would bang the floor, but it would be really restrictive.

 

So you think it would be worse then running dual cats on the Y ?

 

yep.

The flow rate of each cylinder bank is only that of 4 cylinders the flow rate after the Y is double. So a cat would have to handle the flow rate from 8 cylinders.

 

I would run two even though it is more money it will be worth it.

 

Hi: I Check the specs on magnaflow's website the single highflow cat will work with up to a 6.2 liter engine. If you plan on running this setup in a camaro it won't be legal because your moving the location of the cats. If you plan on running this in a mazda convertion car it maybe legal if the car only had one cat from the factory and you can mount it in the stock location. You would not be able to run the rear O2 sensors in this case just delete them and it would be OK as long as your not in Cali. Hope This helps.