Selling my Helix high flow metallic substrate catalytic converter with O2 bung. This cat is in excellent condition and works well (which is definitely not the case for all high flow cats). If you want to free up your exhaust from the stock converter or get rid of the smell from your test pipe or your race catalytic converter without dramatically killing power, this is for you. The quality of this part is very high from the way it fits to the way it looks (check out the welds and finish). I had the O2 bung added professionally so there'd be a place to place to put a wideband O2 sensor upstream of the converter for accurate AFR readings during datalogging and tuning. I used this on an Evo8 but it should also work fine on an Evo 9.

I will sell for $175 shipped within the continental USA. Please use PayPal.

Thanks,
Rich



Helix high flow metallic substrate catalytic converter for Evo with O2 bung

 

Did you happen to run the same car with this and a test pipe, to compare? If so, I have a couple questions:
Did this quiet the car down? If so, how much?

 

My test pipe has a large Magnaflow muffler welded in. The car is slightly louder with this cat.

 

Still available!