cat or no cat

[nieto6.5 td]

do i need a catalyctic converter for a '94 6.5 td. last inspection they didn't hook up the prode in the tailpipe.:confused:

[DmaxMaverick]

Welcome to the Forums!

It all depends on your state's requirements. Some inspections are visual, so if you have a "cat looking" device in your exhaust, it may be a pass. There's not a lot they can tell by probing the pipe on the older trucks. Mostly, probing about soot opacity (black smoke output level). If your truck is properly tuned and healthy, the opacity should be a pass.

If your state requires a cat, and inspects visually, you can modify the cat to make it "inert". This, of course, would be for off highway use only, to retain political correctness.

[nieto6.5 td]

i live in texas

[bbtlr3]

Is there much benefit to removing the CAT? I've heard it both ways some say they are the most restrictive part of the exhaust. And some say they don't restrict very much until they start getting clogged up. Another question I have is, are the CATS on our older diesels any different from those on gassers?

[sailun]

Yes, it makes a huge difference. Imagine your exhaust 80% restricted.

http://www.thedieselpageforums.com/photopost/data/500/medium/Cutdown.JPG

[TurboDiverArt]

Yes, it makes a huge difference. Imagine your exhaust 80% restricted.

http://www.thedieselpageforums.com/photopost/data/500/medium/Cutdown.JPG
I agree. I picked up better drivability and a solid 2-MPG highway. Turbo seemed to spool a little quicker too with the stock exhaust and DP in place.

[bbtlr3]

i live in texas

I looked online and it looks like with the way Texas' rules are written they will be looking under the truck to see if the CAT is where it is where it's supposed to be. But if you know someone that runs a shop and is willing to take the risk.......