I just joined the site. Great place so far!

I have a 97 F150 with the 5.4 V-8 in it. I have ran Magnaflow exhaust from behind where the two pipes come together under the cab all the way back. I was tossing around the idea of running true duals on it with some glass packs.

My question was, if I cut the pipe before where the two come together and go through the O2 sensor, what kind of problems would I run into?

Someone told me that it would just throw the check engine light on, but nothing else would go wrong. Someone else told me that it would throw the light on and cause the computer to effect your gas mileage. So who's right??

I figured with true duals, you would get better gas mileage, but I don't know if it would effect anything with the computer or hurt anything like that. I realize the emmisions would be off, but didn't know about the gas mileage or computer doing anything different.

If I could find an O2 simulator to put in it for fairly cheap, that would work too wouldn't it?? Then I could cut the pipe, run true duals like I want, and throw the 02 simulator in there and wouldn't have any problems? Correct?? I would just have to find a simulator.

So which route do I need to go if I want true duals??

Thanks in advance for the help.
BT

 

just get another magnaflow muffler and ur best off i think glass packs are illegal arent they? if u want true duals get an X pipe or an H pipe depending on what kinda sound u want it to have H sounds best but X hast slightly better performance and only reason u would throw a CEL is if u removed or altered ur cats

 

The part I was asking about is on the factory pipe. I cut it back behind where they come together as one pipe and replaced it with the magnaflow system. The O2 sensor is on the factory pipe still where they both run together. I was going to cut it before that and run true duals coming back. My question was if that O2 sensor only reading off of one side would effect my gas mileage and throw a code for the check engine light to come on. Right now it looks like it is reading both pipes on the factory part of the exhaust that I left alone. The sensor is right on the weld where they come together. Hope that clears it up a little more.

 

Aren't the 97's the same as the 2001's that have 4 O2 sensors? My passenger side back O2 sensor was before the y connection, so I cut off the point where the two connected and ran duals from that point, leaving the O2 sensor where it was. I got a Magnaflow system that is a DIDO system meant for the Harley edition F150, which is a factory dual system.

 

That sounds the same as what I have now. I just had an afterthought and wanted to go from "good sounding" to loud. I have it cut behind the Y pipe and running a magnaflow muffler with one pipe in and two out to the tips.

I want to run two pipes straight from the manifold back. Seperate pipes all the way. How can I do this without messing up my fuel economy?

I talked to a guy at a muffler shop today and he said there is an O2 sensor in front of the cat and one at the Y. The one in front of the cat is for fuel, the one behind is to tell if the cats are working. But my question on this was, why can I only find one O2 sensor on each side?? On the driver side, the O2 sensor is in front of the cat, on the passenger, it's at the Y, behind the cat. Can someone explain that one to me? Or tell me where the other two O2 sensors are? I figured there would be one before and after the cats on both sides, or atleast one in front of the cats on each side, then one at the Y. Got me on that one.


If there is an O2 simulator that would fix all this brainracking that I'm doing, someone just give me a link and tell me to stop worrying. LOL.

Thanks in advance.
BT