If you're looking for a high flow cat, i have one you can buy. It's a bolt on, and i only had it on my GP for two months. It has no U-bend, and made a sweet sound. You could hear the increase in flow. I had it coupled with my cat back exhaust. Reason i swapped it out is because the turbo kit i bought came with a cat. If you're interested, i can send you pictures. You can email me at simonmw75@comcast.net