I recently decided to go with Magnaflow instead of a Gibson cat back. I am thinking about doing the Magnaflow dual in/dual out set up to duals out the back on my 97 F150 4.6L.

I also just had the motor rebuilt and the O2 sensors were left unplugged for a couple months and now once in a while I smell the cats (probably from excess fuel dumped into the cats).

Should I replace the 4 cats and go to 2, replace 2 of the four, or leave them all alone??

Should I go from the cats, to the di/do muffler which supposedly has an internal x pipe or should I just use a si/do muffler??

Is mandrel bent tubing neccessary or can I have a local Meineke do the install??

Finally, can I purchase this stuff through you and if I call the number in your sig...do I get to talk with you??

Thanks so much...you are very helpful to this board and F150 community. Thanks again for your time, Matt

 

I posted in the chips forum, thinking he would respond quicker...is he still around he on the weekends??

 

Hi Matt!

Sure, we can provide all the Magnaflow parts you'll need. Given what's happened to your present cats, I'd say just go ahead and replace them with some nice new high-flo mirror-polished Magnaflow units, one on each side. The factory catalytic converter arrangement has a pair, a primary and a secondary catalytic converter on each side on most of these late-model F-150's, but when you replace them with aftermarket high-flo units, you use just 1 on each side. We can talk about that more in detail when you call, we may find you can continue to use your present units, we'll just have to see when we talk.

The Magnaflow muffler you're talking about does *not* have an internal X-pipe, but it does have an internal H-pipe. The use of an X-pipe is done to not only balance the exhaust phasing of both cylinder banks (which is what an H-pipe does, which used to just be called a "crossover"), but to also accelerate the velocity of the exhaust stream based on pressure drop. This increases scavenging and that brings up torque, and to work correctly it has to be as close to the catalytic converters as possible, so we do not want to have the internal H-pipe in that Magnaflow muffler used as a substitute for a proper X-pipe in a true dual system.

We can go over everything else in detail when you call, and yes, you can speak with me. I spend the majority of my time on the phone, and have to set aside time to respond to all the posts here and our emails personally as well, so it's possible I'll be on another line when you call or working on email for example, and thus not be available at that particular moment. But I'm generally available, even if I have to call you back in a few minutes, etc., it's not hard to reach me, and I'll be happy to deal with you personally, of course.

Nice to see you here again, by the way, it's been awhile, keep in touch!