I'm ordering one for my swap, my understanding is it's a bit longer, and has a 2.5" collector. A stock cat will not fit, people seem to either run a test pipe to span the gap b/t the collector and the exhaust, this will have the 2 bolt flange on the header side, and the 3 bolt plate on the exhaust side, not very green, wouldn't do this personally. Or get a magnaflow (carsound line) cat that is shorter and have it fit up at the muffler shop. But I don't believe it is so long as to be a complete cat delete, however, there are many copies floating around of this design so I'm sure it varies.