Im going to be removing my catylitic converters and im wandering if ift will inprove my mileage or make my fuel mileage worse? If it will make it worse then ill not take them off.

 

To start w/, it is a violation of Ferderal law & most state's law. It will increase mpg & H/P a smidge, but you should keep the O2 system to keep the EEC happy.

 

Doesn't really do anything for milage unless there stoped up, and u might notice the truck revs quicker with them off. And make sure u keep the 02 sensor in the exhaust close to the manifold and I do believe 96 trucks have two 02 sensors and will run a light no mater what. If you do not run the 02 sensor your truck will run very very rich possibly hurting instead of helping. Been there done that

 

you also need to watch out for the egr valve as it will cause the check engine light to come on and if you're wanting the sound i suggest going with a cat back system instead of removing the cats as then you will still be with in the law and get the sound

 

No o2 input to EEC = Failsafe Mode (BAD,Bad,bad...)

 

You will not be able to sell the truck W/O cats.

It will not pass the safety.

Also as already has been stated, the fines for removing the emission control / pollution equipment are usually high.

 

The only way to get away W/O cats is to install a full cat back system and then you will be in with fed and state laws.. to be safe i would suggest to check out the laws in you're area first before removing the cats to see if a cat back system is legal

 

Oklahoma has no vehicle safety or emission laws. http://www.dmv.org/ok-oklahoma/smog-check.php

 

then you should be able to get away with a cat back system

 

No effects, no difference with clean cats or no cats.