Gears

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My fox is mostly stock and I intend to keep it that way. I have heard that if I want a little push without multiple motor mods I should consider gears. It's a weekend cruiser that I will take on the occasional highway road trip. I have gotten suggestions for both 3:55 and 3:73. I am leaning toward the 3:73's because I want the most bang for my buck but I don't want the engine screaming in 5th gear on the highway either. Any advice would be much appreciated

OK. You have:

Lighter weight Fox body
Manual tranny
Mostly stock weekend cruiser
Stock sized 25.7" tires

So the best way to go, without any doubt in my mind, is with a 3.55 gearset.
 
I've got the 3.73's in mine. Hated them when the car was primarily stock, for the same reasons Mike did. It may feel a little zippier down low, but the engine just doesn't have a wide enough power band to take advantage of the additional gear and you're through it before you've had a chance to take advantage of the 5.0L's torque curve. A set of 3.27's-3.55's would be better gear for a basic bolt on 5-speed car IMO.

I did my H/C/I 331 engine swap last week and the 3.73's seem better matched to it, but.....it makes power for almost another 1,000RPM over the stock 5.0L. Quite frankly, the first two gears are just retarded now. My buddy has an '06 GT auto and he's looking for a set of 3.73's for it. I'm seriously considering swapping rear gears with him. His '06 has 3.31 rear gears currently. I'm a little leery now as my car likes to chug and buck at anything below 1,200RPM (CompCams XE274HR). Maybe with some more fine tuning I'll be able to smooth it out. :shrug:
 
how tall of a tire are ya running? playing around with this calculator http://www.bigblockdart.com/forum/speedtire.php

5 speed has .67 OD ratio??

with a 25.5" tire and 3.55 gear you'll be turning 2200 rpm at 70mph..
same tire and a 3.73 gear you'll be turning a hair over 2300 rpm at 70 mph.


i have been trying to figure out what gear i want for my car also.. year ago when i had my 90 lx i went 3.73 gear. it was fun as hell around town and still cruised the highway good but boy did the gas mileage take a hit.. this time around my 87 lx is more a family cruiser but the 2.73 gear is piggish around town. i have been really thinking of going to something like a 3.27-3.31 gear. i figure they should help around town but not kill my mpg while cruising. i really want to do mustang week in myrtle beach one of these years so i don't want to kill mpg too bad for that 9 hour trip.
i tried using that calculator but i wasn't sure which trans to pick. I think they were all Mopars for Darts right? I picked the only one that had a 5th gear and the 55's and 73's looked pretty similar. I wonder if there is a calculator Mustang specific?
 
here is my take on the gear selection assuming the tire is about 27-28" tall

auto stockish: mostly city-3:73 mostly highway-3:55 track-4.10
auto w/ Intake/ TB/Headers/Exhaust/Cam/Tune city:mostly city 3:55 mostly highway 3:27 track-3.73


stick stockish: mostly city-3:55 mostly highway-3:27 track-3.73/3.55
stick w/ Intake/ TB/Headers/Exhaust/Cam/Tune city: mostly city 3:27 mostly highway 3:08 track-3.55

forced induction/ 400whp+:

auto: city-3.55 highway-3.08 track 3.55
stick: city-3.27 highway 3.08 track 3.55
 
i tried using that calculator but i wasn't sure which trans to pick. I think they were all Mopars for Darts right? I picked the only one that had a 5th gear and the 55's and 73's looked pretty similar. I wonder if there is a calculator Mustang specific?


it doesn't matter.. just manually put in the OD ratio and it will calculate properly..
 
here is my take on the gear selection assuming the tire is about 27-28" tall

stick stockish: mostly city-3:55 mostly highway-3:27 track-3.73/3.55
stick w/ Intake/ TB/Headers/Exhaust/Cam/Tune city: mostly city 3:27 mostly highway 3:08 track-3.55

forced induction/ 400whp+:

auto: city-3.55 highway-3.08 track 3.55
stick: city-3.27 highway 3.08 track 3.55

If only it were that simple. Not all H/C/I packages are created equal. The selection of components you run is going to dictate how much gear you'll be able to run as well. Big breathing heads and aggressive cam profiles don't like lower (numerically) gear sets. Big cams will buck at low RPM cruise speeds and combined with big breathing heads and intake may feel sluggish most of the time in a small displacement 302 without some RPM to keep them within the heel of their power band. Most healthy H/C/I cars would throw a fit with 3.08 gears.

I'm still on the fence about the 3.73 to 3.31 gear swap in my Fox. The car only weights about 2,900lbs and makes plenty of torque with the stroker. I just don't want to end up compromising too much of one thing, for another.
 
Used the search to try to find some advice for gearing on the new toy. I am surprised there was no use the search tool post. Anyway I had 3.73's in my first fox (a 5 speed) back in 2004 and I liked them, but I do remember hating them driving down the MASS pike. Like Mike said highway speeds in MA are typically above 80, in the slow lane.

Back then i remember people were totally against anything under 373. It was 373 for stick 410 for auto, and some people even thought 410s were fine for sticks.

I think it really depends on the combo you are running and how you like to drive the car. I think 355s are going to be the right gear for me and they will be better suited for a mild h/c/i combo
 
I ended up going with Ford Racing 3:73's and I absolutely love them. 1st gear is pretty short now and doesn't serve much of a purpose, 2nd thru 4th the car is like a rocket - never imagined I would get this much response from my stock 5.0, and 5th is great on the highway. Cruise at 75-80 under 2500 rpm. The coolest thing probably is cruising at 40 mph in 4th, putting my foot in it, and I'm pushing 80 before I have a chance to look down. Now that's probably a bit of an exaggeration, but it is what it feels like. Putting my Magnaflow catback system on over the next few days. Excited to see how that changes the car, other than sound.
 
I just got my FRPP 3:73's a few weeks ago and from the performance stand point it's an awesome upgrade and worth every penny. I love how it changed the shift points for casual driving. Where I live and drive there are a lot of back roads with 45 and 55 mph speed limits and with stock gears I was always stuck in 3rd gear and on the verge of shifting into 4th but never really could. Now with the gear swap I can comfortably shift into 4th like a "normal" car at 45 mph without the car bogging and falling on it's face.
 
Can't believe there were 3 pages of gear talk. Guess people are just getting older and the 3:73 craze has worn off. Back in the day there was no much talk about any other gear choice but 3:73's and some would throw 4:10's in the mix for the Automatic cars.
 
I ended up going with Ford Racing 3:73's and I absolutely love them. 1st gear is pretty short now and doesn't serve much of a purpose, 2nd thru 4th the car is like a rocket - never imagined I would get this much response from my stock 5.0, and 5th is great on the highway. Cruise at 75-80 under 2500 rpm. The coolest thing probably is cruising at 40 mph in 4th, putting my foot in it, and I'm pushing 80 before I have a chance to look down. Now that's probably a bit of an exaggeration, but it is what it feels like. Putting my Magnaflow catback system on over the next few days. Excited to see how that changes the car, other than sound.

Did you do this...


You will also need to change the plastic speedo gear on your tranny to calibrate the speedo to the new gears.
 
If anyone is interested I just put some 4.10 Gears up for sale..


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That's why there are classified forums.
 
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