Im trying to decide between running the off road pipe(no cats) or getting the y pipe with cats on a set of MAC midlength headers... Will I be making more horse power without the cats? I will need to get 02 sims but even with those will the car run like crap? I plan on using the car as a daily driver so i dont wont it to be obnoxiously loud either...

Let me Know what you guys think...

thanks



96 Z-28 M6

Mods: Borla cat back, k&N CAI, AIR foil

 

I just switched to an ORP on mine, I've got 94/95 style SLP headers and the Borla catback and I think it honestly sounded better with the cat. It's sounds good crusing and at WOT but it makes a loud "thumping" sound when getting on it between 2-3000rpm, I really don't like it much, sounds too ghetto to me. I have a "custom" block off plate in the borla now, I cut a hole in the full blockoff plate (which I never used) between the sizes of the 2 biggest holes. Maybe it will sound better with the larger plate with less restriction, I'll have to try it and see. If not I had the ORP made up so I could switch between that and the cat, I'll probably just swap the cat back in and just use the ORP at the track.

 

Did you notice any performance gains with the ORP, or was it just noisy? Did the car run well without the cats or was it throwing codes?

 

I havn't been back to the track with it to see yet, no real noticable sotp gain but I would guess it could be worth 5hp over the stock cat. It runs just the same, just sounds different, I already had the rear O2's programmed out so no problem with any codes.

 

If you want louder and more power then go with the O.R.Y. However you will definitely not pass smog with it.