Hi,
here in germany is a mini tuner who modify the oem header with a power gain of dyno proven 10 HP and 10 ft of torque.
He open the flange on top of the first cat and remove him totaly then weld it again together. Nothing is visibly from outside and it is very cost effective. The tuner sais no aftermarkt header has more power gain.
Mick

 

I have done this to my car as well. The precat is removed and the flanges are port matched to the ported exhaust on the head.

Gave a very nice increase.

 

would you guys post pictures and links. thanks

 

How much would this mod cost? Also, wouldn't removing the cat make you lose some torque....

 

no, they're removing the pre-cat, not the main catalytic converter :smile:

and yes, typically when you remove restriction in the exhaust you lose low-end torque but gain higher RPM torque

 

Oh alright, i hadn't noticed the 'pre'....The question still remains, how much would it cost to have someone do this for you?

 

I think it shouldnt cost more than 150-200. This is all labor and a fair bit at that.