While looking for a cat back for the 2004 2.3L Duratec, I ran across this dyno plot for the magnaflow on the 2.3L.
Looks to me like they lost some significant tuning under 4000. Has anyone run this system? Can you notice the loss.
I have an automatic, which, yes, I know, I'd rather have a manual, but which would definitely suffer from the loss at the low end.
Any thoughts? A better cat back for the 2.3L? Thanks.