3.55 or 3.73?
 

which one gives me the most power gain without sacrificing gas mileage. I have a 5 speed

Neither are going to give you a "power gain".

But a 3.73 gear being steeper with put you in your power band faster and feel much more torquey and powerfull. The difference in fuel between 3.55's and 3.73's in hardly worth mentioning, IMO.

3.73's are perfect for a 5 speed car. That's what I have ;) .

If you are worried about 1/4 mile times the 3.55 gears suck for the 1/4 mile they will have you hitting 4th gear right as you are crossing the line and it will kill your ET. 3.73's are a better all around gear for drag racing.

IMO,

You should be thinking about 3.73 vs 4.10. and a simple solution to that is the new 3.90's that are out now:D

Hey there,

I just had 3.55s installed in my mustang. I also have a 5-speed. I like them, but it still seems strange cruising around town at 45 MPH in fifth gear!

The 3.55s will get better gas milage than the 3.73s, but it will be a very small difference. It all depends on what you are planning on doing with your car. If you plan on doing alot of highway driving, I would stick with the 3.55s. Although I don't think I will be driving mine on the highway much now, it just tacks too high for me at 70MPH with the new gears. 3.73s would be worse.

As stated above, the 3.73s will put you in your power band much faster, and you mustang will be quicker with the 3.73s than the 3.55. But for a daily driver, I would just stick with the 3.55s.

Let us know which way you go!

Harry

I would go with 3.73's. I have them in my AOD and they are great.

3.55 or 3.73?
 

There is not much difference between 3.55 & 3.73 gears. 3.73s got my vote. I wish they had the 3.90s back when I changed my rear gears. And believe me, 3.55s do not tach high on the freeway. Maybe 3,000rpms at 70mph. Probably even lower, which is not high, at all. Ford still puts out 3.27, 3.55 & 3.73 in many of their production vehicles and trucks.

I have 3.73 and at 70 mph on highway i am taching 2300 and get about 22-23 mpg. Skyman has 3.73 and he gets the same and he has a cam and heads setup so it's b.s that 3.73 kill your mileage. at 2300 i am running about 70 and at 3000 i run 90 mph.

Who make the 3.90's?

Go with either 3.73's or 3.90's

I get better mileage in town with my 3.73's than I did with my 2.73's. Of course my 2.73's got way better highway mileage. But 2.73's suck.

I have 3.55...I wish I went with 3.73...:(

My 88 ran must faster with 3.55's than it did with 4.10's, but the shifting right at the finish line is true with the 3.55's, but I would definitely go with 3.73 over 3.55 if your going to drag it, but for the street I would run 3.27's, the 3.27's ran faster on street tires than the 4.10's and the 3.55's, let us know what you decide to go with

Kenny

I'd go with 3.73 but I would also look into the new 3.90's also... I would like to try them out! I took off .5 sec in the quarter by switching from 2.73 to 3.73! 2.73's sure were fun on the highway though!

When I went from 3.08's to 3.55's, My milage went up. don't know why but it did. ( Yes I changed the speedo gears) But I wish I went with 3.73's. It still fells like too tall a gear most the time.

where do i get 3.90's at
 

where can i order 3.90's at?

gears
 

Just go for 4.10 baby! I had 3.55 and 3.73 before, forget about 3.55 when you compare to 3.73 and forget about 3.73 when you compare to 4.10. It is alot more fun with 4.10, highway driving ? no problem just a few hundreds more RPM on the tach, no big deal !!! No more drop to fourth to pass somebody on the highway with 4.10 you just step on it and swooshhh!!

Doh they make 3.90's I just put 3.73's in my stang. I would have to agree the difference between 3.55's and 3.73's would be very little, but at the track you would be just hitting 4th at the end of the 1/4. 3.73's would have you well in 4th

3.90's?!! Hey i want those. I have whatever came stock with the 89 LX, i think there 3.08's but i could be wrong

Who builds the 3.90's?

Put in 4.56's and a viper T56 with the .50 6th gear! Awesome highway mileage and a nasty whiplash off the line!