3.73 Gears. Too much?
- Thread starter JustaMustangguy
- Start date
2.73s suck. I'm installing 4.10s if that tells you anything. My friends that have 3.73s love them when they're out ripping on their cars but you'll hate them if you DD your car and putz around
nope, not too much, First gear is not useless, it still does its job. First gear should only be used from a stop imo, but with a set of good tires, first gear is the best one.
I daily drove my car for years with 3.73's never minded them one bit, I actually could barely tell a difference from 3.08's. When I put the slicks on is when I noticed a big difference.
I daily drove my car for years with 3.73's never minded them one bit, I actually could barely tell a difference from 3.08's. When I put the slicks on is when I noticed a big difference.
lancec2c30
Member
ReefBlueHatch
Active Member
I have been wondering the same thing, I've been debating between 3.55s and 3.73s. It's my DD (for now) and I have 3.08s now and I am thinking I won't notice much difference with 3.55s.
metalman85
Member
for those of you who have 3.73's in their DD, what RPM does it run at 55mph? and 70mph? with my stock gears 55 is just a hair over 1500 rpm.. with a built 351 i still get decent mpg. but i also would like to run 3.73 gears. i just dont want to run at 2500rpm down the road all day long. its a stock 87 rearend.. so they are 2.73's i believe now.
I havent driven my car in about a year so I cant tell you off the top of my head but on the highway in 5th the rpm's are around 2500. If you have some mufflers that drone it may get annoying, I used to have flowmasters and I have bullets now and I never minded it, but I always loved loud. Other may hate it.
The biggest difference u will notice is where the rpms are when you are driving. I got my gears installed years ago by Jake Lamotta and on the way home I hit it a couple times and to be honest with you I didn't notice a difference in quickness, I just noticed the rpms were slightly higher. Not outrageous, you get used to it within a matter of days and realize that's how the car should run. Like I said before once you get a set of real tires on the rear end you'll wish would have done it sooner.
The biggest difference u will notice is where the rpms are when you are driving. I got my gears installed years ago by Jake Lamotta and on the way home I hit it a couple times and to be honest with you I didn't notice a difference in quickness, I just noticed the rpms were slightly higher. Not outrageous, you get used to it within a matter of days and realize that's how the car should run. Like I said before once you get a set of real tires on the rear end you'll wish would have done it sooner.
RPM will vary with tire size and trans
to metalman: ditching the 2.73s is one of the best mods you can do...
to metalman: ditching the 2.73s is one of the best mods you can do...
TwoToneHatch
Active Member
I have 3:73's in my car and I drive it everyday. IMO 3:73's are perfect they really woke up the car(it had 2:73's from the factory) and the RPM's arent that high. I still knock down 15 to 16mpg easily. I would probally get more if I babied it all the time.
I live in Indy, so I'm on the highway running 60-70mph all the time. I have 3.73s, and IMHO, I wish I had a little more gear in OD. They aren't terrible, but it's a liiiiiiiiiiiiiiiiiiiittle too much for highway cruising. Just a little. I've never driven a 3.55 car, so I can't say if that would be much better. I have, however, driven and ridden in 4.10 cars, and I think you 4.10 guys are nuts. 4.10s should be reserved for the drag strip.
The 3.73s are good for accelerating, though. 1st isn't bad on a decent set of tires.
I think, in the future when my car is making 400+ rwhp and I make the switch to 31 spline axles, I'll probably make the move to 3.55s or 3.27s. I actually wouldn't mind only using 3 gears in the 1/4 instead of 4...
The 3.73s are good for accelerating, though. 1st isn't bad on a decent set of tires.
I think, in the future when my car is making 400+ rwhp and I make the switch to 31 spline axles, I'll probably make the move to 3.55s or 3.27s. I actually wouldn't mind only using 3 gears in the 1/4 instead of 4...
25thmustang
Mustang Master
Been in cars with everything from 2.73s to 4.30s... Its 100% a personal thing, but 3.73s seem to be the go to gear. 3.55-4.10 is where most people stay. Most love their 3.73s, some live for 3.90s, some will say 4.10s or bust, others want 3.27s.
LOL, its all about you. I have 3.73s. I like them, not sure if switching would help or hurt, so I'm leaving them be.
LOL, its all about you. I have 3.73s. I like them, not sure if switching would help or hurt, so I'm leaving them be.
ReefBlueHatch
Active Member
Check out this gearing calculator,
Ford Mustang: Mustang Tech: Calculators & Decoders: RPM Calculator
I hate em. I'm seriously debating stepping down to a 3.55.
3.73's just are too much shifting. I hate being in 3rd gear cruising down the street and running at 3000RPM on the highway.
I don't even drive much and i don't like them. If you drag race a lot you might like them, but if you are like me and just go out for a ride, i'd stick with 3.55's.
Part of me even wants to do 05+ 3.31's out back
3.73's just are too much shifting. I hate being in 3rd gear cruising down the street and running at 3000RPM on the highway.
I don't even drive much and i don't like them. If you drag race a lot you might like them, but if you are like me and just go out for a ride, i'd stick with 3.55's.
Part of me even wants to do 05+ 3.31's out back
FWIW, years back everyone said "3.55s for stick cars and 3.73s for AOD cars". Now its more "3.73s for stick cars and 4.10s for AOD cars". IIRC, the FRPP catalog back in the day used to recommend the "3.55s for stick cars and 3.73s for AOD cars".
Sorry... Lots of acronyms in there.
Sorry... Lots of acronyms in there.
88-378
Member
I am running 4:10's. However, my car is a little heavier with it being a vert and the fact that i added, Full length subframes, matrix brace and jacking rails.
95% of the newer mustangs use 4:10's due to weight.
It's basically personal preference. My car is a weekend nice weather toy. If it were my DD, i would have 3:55's.
There really isn't THAT much difference in RPM.
95% of the newer mustangs use 4:10's due to weight.
It's basically personal preference. My car is a weekend nice weather toy. If it were my DD, i would have 3:55's.
There really isn't THAT much difference in RPM.
89_LX
Member
I haven't driven my car recently so I cant give an exact rpm but at 55-60 the rpm for me are around 2,300. First gear is a little short but its worth it for all the times when you want to have Fun with the car
My car had 2.73's when i bought it and I couldnt even use 5th gear unless i was going at least around 65mph. The only way I would swithch gears i think is if i ever put in a 6 speed.
My car had 2.73's when i bought it and I couldnt even use 5th gear unless i was going at least around 65mph. The only way I would swithch gears i think is if i ever put in a 6 speed.
87GT Drop Top
Member
I have 373 in my car. I run stock height tires. At 70MPh I'm @ about 2700 RPMs. I like the feel of them, but the suck on the highway. Like most people my car isn't a daily driver. It spend most of it's time in my garage.
metalman85
Member
i appreciate the information. BlueReefHatch, that rpm calculator was very useful. thank you. after playing around with tire sizes and putting the gear ratios in for my transmition, i have decided that 3.55 will be my gear of choice 
based souly on highway speed. i plan on doing a lot of long road trips this summer.. 3.55 with my tire size at 70mph will have me growling down the highway at a reasonable 2,206 rpm's
based souly on highway speed. i plan on doing a lot of long road trips this summer.. 3.55 with my tire size at 70mph will have me growling down the highway at a reasonable 2,206 rpm's
