I'll defer to your knowledge on that. I grew up building V-8s, but have been stuck behind a desk crunching numbers for most of my adult life. I can still work my way around engines and most cars in general, but my knowledge of the configurations these days is lacking.
The few I-4 FWD cars I've had have had the cat farther down the pipe near where the passenger seat would be. All were pre-2010, and of what I have now, none are newer than 5-years old. The one AWD I-4 I have is much the same. Is this more on performance engines or pretty much taking over all of them?
It’s pretty much on all of them these days. It’s not even ‘new’ - the Jaguar XJ6 (RWD) with the big inline six had a pre-cat next to the exhaust manifold way back in 1979. Increasingly tight emissions regs mean that this practice is common now and probably going to be across the board for everyone in not too much longer. The closer the cat is to the exhaust manifold, the hotter it is and the better it works.
Pretty much de rigeur now. The below link is a pic of the exhaust system from the newer 5.0L Mustangs - the cats are bolted directly to the exhaust manifolds on those.
