Dual exhaust, does it matter if . . .

[88grandmarquis]

This is sparked by the reading of a different post. Does it matter if the cats are removed from an '86 EFI 302 (original cats) in effect of the O2 sensor? I was reading about the newer trucks and that they may have issues with the computers. Would the old EFI 302 be effected as much?

Three weeks after I have my cat back duals put on, I found out that there is a shop nearby that will remove the cats and put true duals on for the same price as what the cat backs cost me. Needless to say, I'm mad.

[Phinxter]

Why do you want to remove them? You probably won't see much if any of a performance increase without them, unless they are clogged. To try to answer your question I bet the truck problem you are referring to had to do with O2 sensors after the cat, and what this does is monitor cat effieciency, I'm willing to bet an '86 Ford didn't have them, this is more of a modern setup. The O2(s) before the cat is all you probably have, and as long as you have it (or them) in place it should work just fine.

[Cool1996]

You will notice a HUGE difference in performance as i did when mine went bye bye and flowmasters came along. if there is no o2 sensor after the cats then you are good or if it is older than 1995

[jessfactor]

Originally Posted by Cool1996

You will notice a HUGE difference in performance as i did when mine went bye bye and flowmasters came along. if there is no o2 sensor after the cats then you are good or if it is older than 1995

like Phinxter said, unless they are clogged, there wont be a huge difference.

cool1996: how did you notice a HUGE difference if you are not even old enough to drive the truck (i'm going from the info in your gallery). to see a HUGE difference you have to drive it alot, then make a modification, then see the difference.

[Cool1996]

i have my permit and i drive all the time. about 750 miles a month

[jessfactor]

Originally Posted by Cool1996

i have my permit and i drive all the time. about 750 miles a month

the difference you saw was probably from the new pipes and flowmasters. i think the performance would have been close to the same if you left the cats on. the stock exhaust and pipes is what causes the restriction, not the cats. removing the cats is only good for a nicer sound and poluting the air.

[Cool1996]

i had the flowmasters and it was the same performance as stock. it sounded bad too. i took the cats off after the flowmasters were on and thats when i had a difference. i think they were partially clogged