Deciding Gear Size
 

If the car is supercharged then 3.73. If not get the 4.10's. I'm not sure about the installation kit.

will the 4.10s run high on RPMs while Im on the highway?

zUse the gear calculator found on this page: https://mustangboards.com/general-te...ar-thread.html

With my 5-speed and 4.10's I turn 2100 RPMS at 75MPH. Seems pretty low to me.

Dave

with my 5speed and 4.10s I run like 2200 at 70 mph lol

here's a pic of 5th doing like 82-83 mph

http://www.csledd.com/ellie/4105th.jpg

thanks yall Im going to go with 4.10s

are you positive those are 4.10's? You made a thread about them not feeling like 4.10's and everyone else who has them thinks they rock so I'm wondering if maybe somehow 3.55 or 3.73 got put in accidently. I would ask the place that installed your gears. Otherwise, did you get the speedo calibrated? I can see it saying 2100rpms @ 75 because thats around my rpm and I have stock gears.

Cant decide between 3.73s and 4.10s?

Well get 3.90s then...
:poke:

the main thing you need to consider is how do you drive your car? I drive on the interstate everyday and I still get about the same gas mileage I did when I had stock gears. It's all in how you drive it. When I had stock gears I went 80 mph every day, once I got the 4.10s I won't go over 70 mph.. so it averages itself out I guess lol. But when you get on it the gas does go a lot more quick or if you cruise around town. But I love my 4.10s and I considered the 3.73s for awhile, glad I didn't get them though :)

PLEASE PLEASE PLEASE

read the gear thread. MattJ put a lot of time and effort into it, and it will answer your questions.

P.S. GET 4.10s!

btw.. 75mph in my car (stock tire size, stock wheels, 5speed transmisison, 4.10 gears) is 2500 rpms /shrugs