What youll lose top end youll pick up bottom end. Tested on a stock motor, headers did jack over 340 logs. Both slightly better than Lo-po logs. I would do it in a heartbeat (and I have had them, as well as cheapo headers and expensive fenderwells too) Warmer motor demands headers and GOOD headers (think flange, heavy walled drop in style, TTI, Dougs, top shelf stuff) would be the only think I would consider after 340 logs (the early Dakota's are very good too, although not as "accepted"). Do it.