Supercharged Cat Delete

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FordTechOne

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It has worked for me and many many other people. Especially people that drag race there modern muscle cars. Thats how I learned about it. Had to do it to a old Subaru I use to own and never had a problem with it
It depends on the vehicle and year. Catalyst monitoring requirements and strategies are far more stringent on modern vehicles than those from the 90’s/00’s. One monitoring strategy overfuels a bank of cylinders and then compares the values between the upstream and downstream O2s. If the downstream does not provide the expected values (due to no cat and being spaced out of the exhaust stream) then catalyst efficiency DTCs will set.
 
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Bodhi

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Thanks for all your input and info fellas. I’ve decided to go ahead and get the SW 1 7/8 catless longtubes with the x-pipe dump exhaust. The problem I’m facing now is finding a tune for the new setup. I’ve contacted Whipple who won’t do anything because it’s catless, and JDM wants me to change a few items from the stage 2 in order to run their tune. Livernois says they can tune but will have check engine light (I can live with this if need be). I don’t have access to do dyno tuning or actually have anyone willing to (Chris at SW has been looking, but no dice). I bought the vehicle second hand and the tuner module never came with the truck so I have to start fresh.
There must be a boatload of owners here who’ve gone s/c’d with catless long tubes with the stage 2 Whipple. So my question to you guys is what did you do to get everything running lickity split meaning no codes and run/performance issues. Any and all info and experience is very much appreciated. Thanks B
 

FordTechOne

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Thanks for all your input and info fellas. I’ve decided to go ahead and get the SW 1 7/8 catless longtubes with the x-pipe dump exhaust. The problem I’m facing now is finding a tune for the new setup. I’ve contacted Whipple who won’t do anything because it’s catless, and JDM wants me to change a few items from the stage 2 in order to run their tune. Livernois says they can tune but will have check engine light (I can live with this if need be). I don’t have access to do dyno tuning or actually have anyone willing to (Chris at SW has been looking, but no dice). I bought the vehicle second hand and the tuner module never came with the truck so I have to start fresh.
There must be a boatload of owners here who’ve gone s/c’d with catless long tubes with the stage 2 Whipple. So my question to you guys is what did you do to get everything running lickity split meaning no codes and run/performance issues. Any and all info and experience is very much appreciated. Thanks B
In the past, tuners could turn off the O2 monitors do that the PCM ignored the downstream sensors and would not set a CEL. The EPA recently cracked down on “off-road” tunes, fining companies millions of dollars for violating the clean air act. One tuner (North Carolina I believe) was even sentenced to prison time. I’d be surprised if you’ll come across someone willing to take that risk.
 

MTF

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Like FTO said, finding someone to turn them off is going be hard.
I only know of two persons with a Stage II Whipple and 1 7/8" LTs running cat-less.
Plus, they're both also running a mono blade 155mm TB
But this was done years ago. Both are not daily drivers!!!

If my memory is still correct,
1 3/4" LTs work better and help to keep the TB from hunting (surging) especially when running a SC for the Raptor.

Just food for thought, have you looked into getting junk yard cats off a 6.2L
I believe the cats are the same on any 6.2L, like from a HD Van or HD pickup.
Just don't tell the junkyard you're looking for cats!!! Just the front complete exhaust.
 
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Canuck714

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With all the power it already makes going cat-less is just a pain in the assss. You might loose 20hp and that is WOT..
Call SW and add the cats to your order, will save you so much ******** around
 
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Bodhi

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I hear you Canuck. Its the extra $1000 price tag that hurts and seeing as I've gone through a set of cats already, thought I might as well just go catless. It's been a struggle trying to find a reputable tune, starting to feel like a ***** so I may just have to go with the hi flows.
 

Nex

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Have an exhaust shop install cats after the LTs. Add O2 extenders and bungs as needed. Should be under $1k.
 
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Bodhi

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Thanks Nex. I’ll probably just have SW put the hi flo cats on if that’s the case for peace of mind. Still trying to figure out tuning and how I would go about it because the whipple tune is locked. Do I just install the headers and get a new device and tune and overwrite or I believe I save the whipple tune to a new device and clear the tune brain and install new tune?
Cody, what tune are you going run
 
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