Does gutting/deleting DP cats require tune?

[makaveli42]

I'm making an appt for my exhaust to get made and if he can make me downpipes for a reasonable price I'm going to have him make them. The guy told me that I might need a new tune after the exhaust is made to delete the front o2 sensors. My Viper tune has the rear o2 deleted but not the front. Do I need to contact Rich @ Viper for a new tune or will the car run ok with straight pipes from the turbos to the mufflers?

the guy doing my exhaust owns a fab shop down the street from me and usually does nothing but Evos but as a friend he will do mine. Sooo idk if on Evos they require a new tune or what if that's why he said that.

any input would be great, I'd prefer not to get a new tune seeing how I just got the Viper tune and TCU about 3 months ago lol

[kevin]

You will want to retain your front o2 sensors. You need them to regulate fuel mixture. Your viper tune will be happy.

[4everRS]

Front O2's are before precats anyway. Won't matter. No need to delete them and as Kevin said they are critical in fueling.

The rear of the engine will need to be dropped slightly with a transverse bar in order to get at the bolts for the DP's. hopefully a bolt won't break. If so, it will require an engine removal.

Rich should be able to slightly enhance the tune for you as you will have much less back pressure with the cats gone. Looking forward to the progress!

[Spidercat]

Front O2's are before precats anyway. Won't matter. No need to delete them and as Kevin said they are critical in fueling.
True, but they are located on the downpipes themselves, right before the precats within the downpipes.
Your exhaust guy can just weld in bungs for the primary O2 sensors on your new custom-made downpipes. That should work just fine. Definitely agree that you want to keep the primary O2 sensors.
Problem is, if it doesn't work well, I'm sure you realize that getting to them is time consuming, to say the least.

[makaveli42]

Thanks for the input guys! I'm glad that I won't need a new tune!