Ok, so i recently traded in my 07 150 xlt 4.6L for a 2011 fx2 5.0 (which I LOVE ). A while back i bought some Magnaflow exhaust parts to piece together dual exhaust for my 07 truck. However I never got around to get it installed. My question is, is what I have still ok to install on the larger engine?
From everything that I've read in the past, you should use 2.5 in. pipe for the 5.4L and 2.25 in. pipe on the 4.6L. What do you use for the inbetween?

What I have are 2 - 2.25 in. 5'' X 14'' Magnaflow tubular style mufflers, and a 2.25 in. X pipe. I also have 2 Magnaflow high flow cats, but dont plan on installing those, at least not any time soon.

I appreciate any info/advice from you "more knowledgeable guys/girls".

 

Personally I wouldn't go less than 2.5". Doesn't it already come with 2.5" exhaust piping?

 

yeah i think that's what it has now, but when you go from 1 pipe out the back to 2 wouldn't you want to go a little narrower? ... IDK this is just the theory that ive read so much of

 

Didn't really pay any attention to you going with a set of true duals. I still don't think it's enough to make enough of a difference. Put this in perspective. My 2008 Mustang GT came with 2.5" exhaust pipes, an additional 300 rwhp and it was still running 2.5" exhaust pipes without the need for anything larger. I think either way you're not going to have an issue. If it were me, I'd sell them, and do it in 2.5" exhaust pipes.