[Tool Pants]

This is a 2003 S owned by Paul in Australia. You can see there is no pre-cat on the exhaust manifold. He just has the rear cat. The 2.5 also did not have a pre-cat. The 4 cat system started in 2000.

Paul and I exchanged hp numbers and the difference was like 1 hp. But if you wanted to elminate the pre-cat I suppose you could buy ROW manifolds. You would need to check ROW and US part numbers to make sure it would work.