I have a 1995 F150 with a 302 EFI. I plan on building up the enging a bit and i am going to start with the exhaust. I plan to put a magnaflow muffler on it and i would like to add new headers. I am wondering if i should take off the old Cats and sell them and buy a brand new high flow cat. I am wondering if it is worth it or just a waist of time. I am also wondering if i would have to buy two new cats or just one it has two cats on it right now stock.

 

buy some long tube headers for it and run no cats....

 

If you have smog inspections then you will need a cat. You can get a single cat, the factory uses 2 different types but aftermarket are all in one. We don't have smog inspections but a cop can look under your truck for a cat and give you a ticket for not having one, so I hollowed out mine.

 

I Think hollowing out the originals is the way to go on this. I have done this to my truck with a set of Clifford headers and am very pleased with the results both with the money I saved and the performance!!

 

I am running Pacesetter long tube headers into a custom true dual exhaust with twin si/so flowmaster series 44 mufflers and chrome slash cut tips.....best sounding truck next to the superduty I have with a Turbo back RBP exhaust

 

i would like to keep it legal. i do live in missouri so its not like running no cats or hollowing out the cats is anything new around here but i just cant afford the ticket or to not pass an inspection. another thing i thought of was to pull the old ones of there and sell them because i know they bring good money which would probably give me enough to buy a new one. but then my question is will the new one performe better than the old ones?

 

You will need cats to pass inspection. The only place I see to get money for cats is the scrapyard, and with only one it can't be that much. New high flow cats are supposed to flow better than stock.
By the way, you will need 2 cats if you have dual exhaust, one for each side. I forgot to mention that.

 

Also, if they don't measure the exhaust pollutants then you may be able to get away with hollowing out the cat. If it's only a visual inspection.

 

Wait, you're saying the cat is supposed to have something inside of it?