svs

Right on otto! Thanks for taking the time to add a pic.

I didn't realize we had 4 cats. Those rear two look to be pretty big.

F-150forlife

So if we still have two, what will the two hi flow cats do then? How would they help exactly? And in what way?

otto457

It's either one or the other. You either have four cats from the factory (04,05, some 06), two cats from the factory 06+. The 06+ can swap high flows directly in place for more sound volume. The 04-06 can either 1. Delete the rear two cats, keeping the factory front two to make it like a 06+ and increase the volume or 2. Replace all four cats with two high flows.

All these are done for increased volume. They increase volume by having less area or affinity for sound deadening.

F-150forlife

So if I deleted all cats and added two high flows and a magnaflow 10416 muffler would it be a lot louder as well as would there be any horsepower or mpg increase?

otto457

It would be louder. The stock cats flow fairly well, any power gains (which are fairly small with any exhaust mod short of headers) would be seen from the reduced restriction of the muffler and the system, not from the cats themselves.

F-150forlife

Awesome thanks for the info

blue thunder06

i would do exactly the same if i had the four cats, but if you do get your OEM cats removed and put in aftermarket. tell the shop you wanna keep the cats, alot of ppl dont realize it but those cats are worth good money at a scrap metal yard. if you took in four cats to a scrap yard, thats a tank of gas right there

F-150forlife

Depends where you are, in NorCal we dot get crap for scrap metal

JCT1990

Pretty sure Its not the scrap metal itself thats really worth anything its the material inside thats worth $$

F-150forlife

Well where could I take it then to get more money?