Wow, 2.94 and a 4.56? What`s going on here? Are these just gears that you`re able to get your hands on? Neither gear seems a good match for your combo. With that 2.94 gear you`ll probably never get into 3rd gear and with the 4.56 you`ll probably run out of engine. The 3.91 you have now sounds like a better gear than either of the other two. With the 2.94 gear I would guess an ET in the upper 15`s, with the 4.56, about what you`re presently running , maybe a smidgeon faster/slower than your best 14.38.