I removed the secondary cats from the car, they are the ones in front of the mufflers on the side of the car. The primary cat is further upstream. The cat has a large amount of substrate in it, and very close honycomb patern. I will say this much, the side sills are very cool, and the car does seem to run better. I'm using Bullet mufflers on the car. I don't see much reason in upgrading the primary cats on the car, as they are probably not that contrictive, since the car ran a secondary cat system. They are in a very hard to get to place. If you are putting headers on the car then I think it would be great to upgrade to high-flow cats, but Random Tech, does not have any for this car yet, unless the former model will. As the car is without headers, no way the former style Random Tech will work to replace the primary cat. Im sure they would work to replace the sec. cats on the side of the car, but why do that since the car will pass emissions with them off, and no check engine issues.
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