Dose the Fuel line go through the CAT ?

Wth? Straight-piping ruins all the fine tuning of the engine because the sensors are sending bad data to ECU. Every car you've ever done this has gotten worse gas mileage and less reliable performance no matter the made up story you tell yourself about why maximizing your vehicle's toxic emissions is a good thing. And it's not the fuel line that prevents removal in a Gen3, it's a coolant line that's integrated into the cat that prevents it.

 

The coolant lines are connected to the exhaust heat recovery exchanger, which is behind both cats.



From left: first cat, second cat, EHRS exchanger (with coolant lines), sub-muffler.

 

umm, ok

 

The Ford excursions in the big diesels the banks and the Cummins and all of them Yes you're right taking off cats and doing all kinds of stuff is legit in that world here in these cars not so much there's so much to fool it's not like plugging in a tech 2 and going on your way. I lived up near one of Gale shops long time ago like in the '80s when he was just getting his start fooling with this stuff and was cool dude cool setup cool garage all that but with these cars especially the hybrids and all that not so much you want to do that you'll be spending your life trying to fool the next something and it just doesn't work that way The electronics people that make aftermarket computers and all they don't even fool with these vehicles because they're so finely tuned. Tree hugging doesn't have a lot to do with it to be honest about it it's just the way the vehicles are made. We have a couple big diesel shops right here in Burlington North Carolina that specialize in all the stuff you're talking about they make big power out of these whatever engines they're working with do all kinds of mods etc etc but for some reason when those things leave out the factory they're almost worse than a Prius as far as running on their own puke goes so guys like Gail Banks and other tuners spend their lives trying to bring these things into the real world if you will That's why I would only buy one aftermarket from somebody that's already dropped all the money to do whatever.

 

So your Excursion is getting more than 1100 miles between fill-ups. That is fantastic!

I always wanted some big diffance doses.

 

Keep in mind, diesel and gas engines are different stories. With the diesel Excursion, your delete was mainly on the EGR and DPF. DPF causes huge back pressure to the engine because it's essentially a soot filter. EGR causes the intake to carbon up very quickly and badly.

With gas engines, deleting cat will have minimal improvement on performance. The cat does not work as a filter on gas engines. If you ever cut open a cat, you will see that inside it is essentially some precious metal nets that don't cause back pressure at all. This is why literally nobody do this with gas engine but the EGR/DPF delete on diesel engines are quite popular.