This is my first post on the forum. I live in a state (SC), that doesn't require state inspections, so i am planning on deleting the catalytic converters, because mine were stolen off of the car, and replacing the exhaust with an x pipe running to the back connected to a set of flowmaster mufflers all stainless steel. Has anyone deleted the catalytic converters with any good results, or will this do more harm than good, does an XKR (2001) need catalytic converters to run fine? I'm new to the forum, so if this has been discussed before, I apologize. And I hope to gain some horse power by deleting the catalytic converters. Thanks for your input.

 

It won't hurt the car and you will gain a small amount of hp, but it will probably cause a check engine light (CEL).

If you delete your rear HO2s I think it will always cause a CEL. Of you keep your rear HO2S without the cats it might cause a CEL depending on their condition (it will cause a CEL if you use new ones).

In any case a hard reset on the computer will make a CEL more likely so don't do it unless you have to.

 

It is illegal of course but can be done. You have to retain the post cat O2 sensors to avoid error codes but as I understand this can be done with spacers to fool them.

There are a few members that have track pipes on their cars that have made it work. For track use only of course.

 

I don't believe the situation he described is illegal under Federal law. It is illegal to intentionally disable an emissions control device but I don't think a failed part (or in this case a stolen part) has to be repaired if the car is over 10 years old.

 

You will get a check engine light for catalytic efficiency. Later you will find to replace these guys is expensive. Without a tune, there will always be a cel. The tune is expensive as well.

 

use some antifoul screw in tips at your rear 02 sensor locations and your CEL will likely be gone forever. You can get them in the HELP section of any auto parts store. They may also be called 02 extenders...But unsure

 

My 96 has stainless bypass pipes and I never had a fault code...but it does have the connections for either 1 or 2 sensors per side

Sounded and went rather well!

 

depends upon the state. in my state after twenty or so years, they no longer test the car or look for the check engine light, safety only, however the registrant is required to maintain the emissions equipment as it was installed when the vehicle was originally certified and said equipment must be in working order. some states also apply this rule to vehicles registered outside of their borders and driven in their territory.

without the proper read from the oxygen sensor i can see you running rich most of the time according to the map. a proper cat delete would require ECU mods which might cost more than simply replacing the missing converters.

 

Clearly no one read my post as have them fitted and no fault codes.

As to performance gains dyno'd at Nobles as running at 323 to the rear wheels, that however is with a carbon dynamic intake, straight through balanced exhaust and running royal purple fully synthetic
Currently selling on eBay for £150 (cost me £400) and of such a high quality stainless that it will outlast the car fitted to....but will only my fit 4lt XK8's (R's have a different cat connection)

Completely possible as DIY with car on ramps and a few extension sockets...and lots of cursing due to grazed knuckles

 

Fitting them on a car used at all on the public highway is illegal in the UK (and EU), though. That may reduce the number of people wanting them.

 

Do you by chance know the length of the pipes or cats... any dimensions would be helpful...( ig, length, angle of the part of the pipe where it bolts up)

 

If you use an extended spark plug de-fouler screwed into the hole the downstream O2 sensor with the downstream O2 sensor screwed in it will keep from the computer from knowing the cat is gone or even bad