OK on the 97 f150 i believe there is 4 cats, right? is there any way to cut out the cats for more tone and loudness without affecting the backpressure and MPG?

 

Yes there are 4 cats on the 97. what most people do is get 2 high flow cats to replace there stock 4 cats. i had a muffler shop make me down pipes just to get rid of the 4 cats and have no cats at all cost about 100 bucks for them to do that... i handed them my cats and they bent the pipe just how the cats were bent so they fit right in.

 

did it add some nicer sound to ur exhaust? and make it louder

 

i went from 4 cats dumped with my Y-pipe choped to no cats with dynomax super turbos....the superturbos were pretty quite so i couldnt tell the diff. in the sound but in my Sig theres a video of my Pacesetter shortys with just the down pipes dumped...open headers. i saw a lil gain in gas milage but nothing to jump around about but every lil bit helps. there sitting in my basement if you want them 50 bucks i only had them on my truck for abour 2 months before i got longtubes.

 

what about those sensors, how did u get around them...did u just but a heli coil in the pipe and put the sensor back in the new pipe?

 

you can do that i got o2 sim's for the rear o2's but some guys claim on the 97's threw 03's you can just get a rear o2 delete and ur truck will run fine... but i think if you just put them back in the pipe it will be fine...The front o2 bungs are in the stock location.

 

Deleting the rear sensors will throw a code but your tuner can turn them off (if you have a custom tune).

Just get some sensor bungs for the front ones, they're super cheap...any exhaust shop should have them in stock and the ability to weld them into the pipes. It's the threaded bung that the sensor screws into. Put them in the same location as the stock ones and you'll be good to go.

I just gutted (hollowed-out) my pre-cats, because we have a visual inspection in my state. It looked like they were there...some guys will have a shop put a pipe through the front pre-cats, this likely flows a bit better then gutting them.

 

The down pipes i had made the guy at the muffler shop put the front o2 bungs in the same location as the down pipes with the cats.