I have a 95 f150 running a 5.0 followed by a 4r70w. I'm wanting to remove the cats and toss them. What issues will this cause with my truck? What else do I need to do in conjunction with this? Thanks

 

A couple of FYI's

1. Removing the cats will really not gain much power.
2. Even though you are exempt from inspections, you are not exempt from the requirement to have them- even US Fish & Game Wardens carry a manual that identifies each vehicle and the required smog equipment, illegal engines changes, etc with pics of how to ID.
3. Any law enforcement officer (including fish & game), EPA inspector, etc. can impound the vehicle and cite it as a gross polluter
4. Once cited, a judge will decide if the vehicle is to be scrapped or returned to the owner- and you do not have any opportunity to speak in court- just required to sit & listen.
5. If the vehicle is returned- guess what, now you have to repair and take the vehicle to a federal referee station for the rest of "its life" for a smog inspection & test.

IMHO, it's not worth the risk versus the little gain.

Here's a link to a "Real Test" that verifies....on a 700+ hp engine......no gain or loss of with or without the cats!

http://www.kennebell.net/KBWebsite/C...aust_tests.pdf

The myth about high flow cats

Clearing Up the Myth About High Flow Catalytic Converters

The oem units are already "Hi Flow cats"....you won't change a thing by swapping.
Under federal regs………up to $2,500 for modifying any emission control device….and lets face it, for the few hp (if any) you will gain by switching to “high Flow Cats”, that $2,500 can buy a lot of real performance!

Straight from the EPA's page and the Federal law trumps state laws, it might pass emissions but ever get a cop with “wanting a reason” for you and you can get hit pretty good.
Quote:
(6) When can I install an aftermarket converter?
Generally, there are only 3 situations when you can install an aftermarket converter.
They are:
(1) if the converter is missing from the vehicle when brought in for exhaust
system repair; or
(2) if a State or local inspection program has determined the existing converter
has been lead poisoned, damaged, or otherwise needs replacement; or
(3) if the vehicle is more than 5 years old or has more than 50,000 miles*
(8 years/80,000 miles for 1995 and newer vehicles) and a legitimate need for
replacement has been established and appropriately documented (e.g., a
plugged converter or unrepairable exhaust leaks).
Any other converter replacement must be with a 'certified' or new original equipment (OE) or equivalent converter.
Aftermarket converters subject to the enforcement policy requirements cannot be used for replacement if:
(1) the existing converter is present and functioning properly; or
(2) the replacement is under recall or warranty; or
(3) the vehicle is returning from overseas use.

http://www.epa.gov/otaq/cert/factshts/catcvrts.pdf

An off road pipe or deleting your Cats is good for up to $25,000.

You will hear people saying they have passed emissions inspections with aftermarket high flow cats……………they were lucky and found a shop that will eventually be fined & shut down…even worse, once that occurs, the state or feds can e-tag every vehicle the shop has passed for the next upcoming inspection and even order you to take the car to a federal referee station.

And with regards to “probable cause”, after market mufflers will give any LEO that and without a warrant or other impound cause, it is “legal” for any LEO to look under the vehicle (since it is outside the vehicle).....CATS missing.....likely say goodby to your vehicle.

IMHO of course....

 

None as long as the O2 sensor remains installed and electrically connected.

Nothing.

 

Beechkid: thank you very much for your greatly detailed reply. I appreciate it.

Conanski: thanks for the info bud. You answered my question perfectly. 👍

 

The links to the Kennebell dyno tests as well as the Catalytic Convertor.org site were pretty good reading, thanks for posting.

I think the most important point that Kennebell makes is that dyno (or other) tests are really only useful if only one change is made at a time, between tests.