Question about cat's

[thekevin]

Will the lack of cat's on a 98 454 cause the engine light to come on. Also what would the factory configuration of the exhaust have been in it. It's a 98 2500 4x4, right now it has 3" duals all the way out.

 

[DRAGGIN95]

Yes if the cat's were just removed and nothing else done then that could cause the service engine light to be on, you need one of three thing, either have the rear 02's turned off in the tune, get rear 02 extensions, or run 02 dummies which make the computer think the 02's are still there. I Have done all 3 and they all work, but the extensions are the cheapest, you can go to a parts store and get some 18mm spark plug non fouler's and drill out the hole in the end to at least a 1/2 in. and install them on your rear 02 sensor's they should thread right on. All the extensions do is pull the 02 sensor up away from the exhaust stream a little, just enough to make the computer think the cat's are still there.

 

[thekevin]

Sweet, that is what I will do. Where in Central, AR are you at, I live in Harrison.

 

[DRAGGIN95]

I live north of Beebe, or about 14 miles west of Searcy.

 

[thekevin]

If I ran a Y and took it all down to a single 3" pipe under the cab, no cat, and a 40 series flowmaster would that be free flowing enough for the 454.

 

[DRAGGIN95]

Yes as long as you keep you pipe's from each side at least 2.5 in. up to the y you should be fine.

 

[thekevin]

Ok, right now it is dual 3" all the way out to gay rusty tips poking out the back right now. I think I am just going to Y it and run a 40 series or super44 Flowmaster and take out a single 3" pipe near the factory location.