[Future303]

Ok, my 95 GT is stock. I understand that the Diff. Gear is 2.73. I want to go to a 3.73 gear, but I am wondering a few things:

1. Obviously Mileage will decrease, for city driving I don't mind so much, but I do a lot of Hwy driving, and if I'm going at 100km/h (about 65 Miles/h) my RPM is about 1.6k. With the 3.73 what can I expect my RPM to be at?

2. I have to get my tranny rebuilt soon. I understand my 5th OD Gear is a ratio of 0.68:1. Is it possible to replace that gear with a 0:50:1 ratio, to balance out the difference on the Mileage and the RPM's? If I have to get the tranny rebuilt, I might as well try to put in that 0:50:1 OD Gear if possible.

I asked this in another thread but didn't get a reply. If anybody knows I would appreciate the input. Thanks.