just curious to know if i went with a set of longtubes, if 1-would they basically bolt right in and 2-how much power/noise gains could i expect out of them? wanting to do something else to my truck performance wise. also, i was lookign at the Pacesetters. any thoughts?

 

The pre-cats would have to go because LTs are much longer and end where the pre-cats do. You can still keep your rear cats, but its not really worth it imo, if your gonna add LTs, might as well have hi-flows to go along with them. But yes it is possible, the pre-cats wont be able to go back in though.

 

so with pre cats out and LT that is all still good for emissions right? what kind of shop would do all of that, just an exhaust place? so basically to do this the RIGHT way with high flows im looking at a bit of cash huh?

 

Well if emissions is the problem, I dont think you can legally change your manifolds out, or go from 4 original cats to two cats ( original or not ). A customs shop, or a good exhaust shop should be able to do it.

 

And if it snows where you live, be sure and get stainless or have them coated, otherwise the salt and cinders will have them rusting in a little over a year!

 

what will shortys do then? will they fit in with precats still intact?

 

They'll make it a little bit louder, not much. Yeah they'll keep the pre cats because they're the same size as OEM manifolds.

 

i put on a set of shortys on a 2002 f150 4x4 factory exhaust the sound did not change untill high rpm then it sounded a lil rasphy but he said gas mileage improved but im sure with long tubes its gonna be a pain putting cats on then runni them back. u could probly keep the them on one side use ur big cat only and extend ur o2 sensor wires. when i was gonna get high flows quite a few young and old mechanic told me that ford's have the highest flow for factory and arent much different the high flow it just that we have 4 instead of 2

 

on my truck it goes 4.6 then manifolds pre cats then punched out big cats with o2' still in them then true duel straights and 5 inch tips no engine lite came on even after 25000 miles and got smog tested and all they said was that my injectors were dirty and i thought cause of the pipes but then i figured thats why my truck had a miss after i already changed plugs and coils ran some injector cleaner no miss at all did all this a 66000 miles now have 91000 miles 14 mpg in town and 21 mpg highway