which catalytic converter to buy

[88Vic]

The stock downpipes are actually 2.25". It goes down to 2" at the H pipe flanges. You need 2.5" flanges at the top end of the downpipe to fit up to the headers, but thats nothing an exhaust shop cant manage with minimal work.

So the factory HO manifold collector size is 2.5"? That should still work, a shop can make new downpipes that reduce 2.5 to 2.25 to 2. I'll reduce it after the first bend, so it doesn't kink too much. I'm not planning any mods aside from lower gears, but still, crush bent 2" is ridiculously small, 2.25" is too, but a 2.5" crush bend will still leave 2" or so, fine for the lopo.

[knucklehead0202]

For the record, stock fox mustang h-pipes were 2.25", and really didn't seem to neck down from the collector, but it is a ball-and-socket type collector, so an exhaust shop may not just have one lying about. If you can snag a mustang H at the junkyard, it might be worth it just to hack off the collectors and part of the down pipe. One thing to consider is that your 02 sensors are on the exhaust manifold on a box, and on the downpipes for a mustang. I bought 02 sensor extenders but my exhaust guy beat me to the punch and just relocated the sensor bungs to work. If you're starting clean-sheet, I guess it really doesn't matter.

[gadget73]

The ball and socket setup is bigger on the HO headers, whatever the measurement happens to be. Its the next size up from the stock crap on the Lincoln.

yeah, forgot about the sensors. Mark VII sensors should be longer than the originals if yours aren't long enough to reach the new bunghole.

[knucklehead0202]

Lol, bunghole....

[sly]

you will give me TP... TP for my bunghole! /Cornholio

[knucklehead0202]

Are you threatening me!? You will give me tp! Hahahah, yeah, I was there....

[DerekTheGreat]

"There is but one bunghole..."