Goodbye 3:73's

[10HoleLX]

I'm swapping out my 3:73's for 3:27's this week. I recently moved 35 miles from my work and my gas bill sucks! I put about 70 miles on my daily driver LX and I can not make it through the week without refueling twice. I've been getting about 260 miles average per tank (all freeway driving). Rpms are at around 2600 at 75-80mph. And I baby the it too! No passing, NO downshifting just cruise everday to work.
Before I moved to this new place of mine I only had to drive 1 mile to work. Usaully I parked the car at home and I would walk or ride my bicycle to work.
Now that my car is a true daily driver,I'm starting to see how these gears suck up the gas!
The 3:27's should drop the Highway speed RPM's significantly to save me fuel and some extra $$. I'm doing the work myself and using a good set of gears that I have laying around. If I ever move closer to my work, the 3:73 will definetly go back in because they are awsome!
Anyone still running these gears in their Fox Mustang? Input would be great.
Thanks
Danny

 

[eliot22]

3.27's should put you at around 2000 RPM's at 75-80MPH. Now you will get to enjoy that wonderful Mustang drone the whole way to work. Just something to consider.

Option #2: Drive Mustang on weekends, get Honda for weekdays. Okay, bad option.

 

[Mike86Stang]

3.27's should put you at around 2000 RPM's at 75-80MPH. Now you will get to enjoy that wonderful Mustang drone the whole way to work. Just something to consider.

Option #2: Drive Mustang on weekends, get Honda for weekdays. Okay, bad option.

Hey Eliot long time no see... what's been going on?

10Hole... I'll be moving to 3.27's once my turbo's make it on. I personally think 3.27 is the minimum gear that should have came in the cars. 3.55's are a nice comprimise & 3.73's are great for street performance. The car certainly won't feel the same with the 3.27's...

As an alternative to swapping the gears you may want to consider other ways of saving fuel.... reducing wieght or parasitic drag on the motor.

Most notably an electric fan pushed my per tank mileage to 320 when I was driving 50miles round trip to work everyday. Granted this was with stock heads & cam but with 3.73's still...

 

[cleanLX]

I routinly knocked down 26mph with stock motor and freeway driving.

My guess is the B cam is the culprit, not the gears.

 

[10HoleLX]

Yeah I know I will hate the downgrade in performance. I went from 2:73 auto to 3:73 manual and we all know the difference that made. I've had the 3 73 in there for three years already. The 3:27's will be temporary, gear swaps are like a "walk in the park" for me so I'll switch if I can't handle the crappy performance.
Already have electric fan conversion (no dramatic fuel consumption changes, less noise though), underdrives, free flow exhaust and just about everything to make the car fuel efficient.
Someone mentioned the "drone", I don't get that awfull tone because I have the Delta flow 3 chamber flowmaster system with x-pipe.

 

[10HoleLX]

cleanlx your probably right, but for now the gear swap is the most easiest modification I could do to get better gas mileage. Motor is super strong and clean to tear into.