Just to add some perspective on the duals/cats/no cats, I have clips in my sig with my high flows, and then with them deleted. I need to get some new videos, my duals have broken in even more and with the custom tune she's certainly louder!

 

You have any motor problems with no cats?

 

Zero problem, haven't even thrown a CEL.

And to reclarify, I only cut out the REAR cats, I still have the 2 precats, the down stream O2 sensors were BEFORE the second set of cats. In this warmer climate it's tough for the temp change for no rear cats to be picked up by the O2's.

I'm surprised Darren up in PA hasn't thrown a code, have heard of a few folks in Canada and AK throwing codes after cutting out the rears.

 

i had a magnaflow muffler on for about 4 months... it was ok.. but i just took it off and put a y-pipe in place and i love it... my mpg have not suffered at all if anything it has gone up... i dont know why but it did and it sounds delshious

 

I haven't thrown any code, and never will. The pre-cats are the only monitored cats in the 2004 - 2005 4 cat systems, rear are not monitored. Removal of them will not hurt a thing except the persons hearing near your exhaust tips

To clarify Dixie, I thought you had your pre-cats gutted, did the shop tell you they would do it but never did? 80% of shops are dishonest like like that. None the less we're both legal IMO, and lucky to have the 4 cat systems so we can chop the rears out and get the exact same affect as hi-flow cats while saving $140 on buying cats, then $150 - $200 for install labor huh You two cat people should be jealious

 

I love that.

 

hate to say youre wrong but when i went from a y pipe to true duals, true duals is much much much louder. this is with all stock 4 cats. although i did go from a 40 series to two 10 series. maybe thats y idk.