Have a 4.2l six in a 2001 with a 5spd manual. I'm wondering if headers & dual exhaust will be worth the $. I seldom go over 3500rpm & don't pull loads. Truck actually runs quite fine as is. Just wondering if there would be much improvement for the money invested. I don't know how restrictive the stock exhaust system is. Anybody have a before/after experience?

 

Nope, not worth it at all. They arent even worth it on the 2V 5.4L until you make over 500RWHP.

Wayne