Hi everyone. First time here. I just picked up a bone stock 04' red auto 350z. I only drove the car for 3 days before doing my first few mods.

I recently had the cats removed, had a strait pipe welded. Resonator removed as well. I purchased a pair of o2 sensor extenders, which i've used in all my vehicles to avoid the p0420 code.

Since I don't know this car so well It may be in my head but I feel a loss of power now around the 2000-3200 RPM area.

Is it just me?

So to sum up now I have No cats, No res, o2 sensor spaced and a stock muffer.

I've heard a ton about back pressure, maybe since the cats are gone the exhaust is clashing at the y-pipe?

Could use some expertise on the matter.

Thanks!

 

you lost low end torque by cutting out the cats, not to mention you are prob running lean now. you could get it tuned to help it out some

 

I felt the same lost of torque after test-pipes install
Go tune your Z as travlee said

 

we have a rocket scientist, what did he think by removing everything

https://my350z.com/forum/engine-and-...wbie-here.html

 

Sounds like a redneck to me.... You might want to sell that beater you just bought and get something that's not covered in plastidip.