I have motive 4.10s on my 04 GT 5 spd. I've had them for almost 10,000 miles now. RPMs @ 70mph is around 2400 for me. Still get minimum 20mpg(usually 22-23 when I can keep my foot out of it). Im pretty sure I could get more mpg out of it, but I drive "very spirited" several times on EVERY...