1/3 the cats
 

why six cats i dont know but i live in NJ and they are killer on emmisions here if i go from the stock six cats to a SLP catted H/X pipe will i still pass emmisions? also i seen in another post that 87 octane is just as good as the 92 octane in the mustangs is this true? cuz thatll save me like $500 a year

unless you are tuned for 93 octane and or have a blower,nitrous or high compression 93 is a waste of moeny.

Yep, just like spike africa said about the octane. For the midpipe, you could always give it a try with the midpipe, if you dont pass then put the stock one back on.

Get the slps and you can put the cats on when inspections come around. The only thing you have to know if they will accept you having 2 instead of 6.

yeah i guess i could just swap it in and out. go with no cats at all. nice sound. im gonna call n see about the 2 instead of 6 thing that was a good idea.