5sp 3.55 vs 3.73

[millhouse]

What's funny is my drone with my flows gets quiter as soon as I reach 75mph. Seeing as I cruise on the freeway daily with my 3.73's at 80-85mph, I actually notice quite a bit less drone than when I'm cruising at 60-70 mph.

 

[SAYNOTORICE]

i have stock ratio 2.73's, and im revving at around 3000 at 85 mph is that about right...my friend is tyrin to convince me that i have 3.73's, cause he had them in his 90 5.0 and he says mine revs the same...i think he didnt have them or either that his tach was f**ked...my moms 00 GT vert with 3.27's feels like it pulls harder than my 5.0....mine doesnt feel like it has gears....who is right, me or my friend?

 

[final5-0]

My brother owns a 88gt 5sp manual. Our next mod will be gears. My friend owns a 99 GT 5sp man and he put 3.73 into his car and I love the ratios. My question is, since the 99+ have 3.27 stock and the 5.0 have 2.73's, will 3.55 in an 88 gt have the same effect as 3.73 in a 99 gt?

There is very little difference between them as far as cruising at highway speeds. We are talkin about less than 200 rpms if I remember correctly.

You will feel the diff between them when you punch it with the 3.73's.

You now have my opinion with all of the others!!!

Go here for the facts about gears

http://www.allfordmustangs.com/Detailed/608.shtml

Later
Grady

 

[Stock89LX]

im also another person with 3:55's who wants them over 3:73's.

i drive on the freeway to go anywhere pretty much, i dont think i could take 2500+ rpms of flowmasters for an hour. right at about 2100 rpm's is where they really start speaking on the freeway, according to my 5" tach im doing 1800-2000 rpms at 70-75

I'm running 2 chamber flows with a Dr. Gas off road X pipe. The drone really drops off at about 2200 rpm, and believe it or not, cruising at 2500 rpm is pretty calm. Again though.... to each his own. I'm happy with my 3.73's, you're happy with 3.55's. Ain't America great?

 

[BelueLX]

i have stock ratio 2.73's, and im revving at around 3000 at 85 mph is that about right...my friend is tyrin to convince me that i have 3.73's, cause he had them in his 90 5.0 and he says mine revs the same...i think he didnt have them or either that his tach was f**ked...my moms 00 GT vert with 3.27's feels like it pulls harder than my 5.0....mine doesnt feel like it has gears....who is right, me or my friend?

with 2.73s and my 25.83" tires in 5th gear i cruiser right above 2000rpm at 85mph. sounds like you have 3.73s or 3.55s. jack the car up, mark the tire, count your driveshaft revolutions -vs- one rotation of the tire. my 91 turns 3-3/4 times and it has a 3.73 gear. pretty simple. gearing makes all the difference. just keeping my daily driver in the 21.69 avg mpg city zone for now. you dont really appreciate it until you have a car with a C4 and 3.73 gear with 26" slicks.

 

[SAYNOTORICE]

according to that i have 3.73s but im sure i dont have em....can anyone else help me, i know the only real way to tell is to jack it up and count the axle rotation, but im at school and have no garage....anyone?

 

[eric88gt]

I can assure you that those are not 2.73's in your car if it's showing 3000 RPM's at 80 mph, unless you're running donuts on the back. I've still got 2.73's in my car (3.55's going in when it come out of hybernation) and it's about 2000 at 80.

 

[SAYNOTORICE]

just drove it.....i am 3000 at 85 mph...is this still wrong?

 

[millhouse]

Sound like you have 3.73's to me. I run around the same rpms @ 85-90mph.

It's either that or your tach is waaaaaaay off...which is quite possible.

The difference between 2.73's and 3.73's is stagering...but unless youve compaired the differences for your self in the same car, you wouldnt be able to know.

 

[SAYNOTORICE]

maybe i do have em....thats probably why when i raced my friends lt1 i put a car on him after 2nd, even from a roll...i guess i am just gonna have to count....and if i do have em...then I WANT 4.10's!!!!!!!!!!!! cause i am not fast enough!!!!!!!!!

 

[91BlckGT]

i run the 3.55, I don't really have an issues with them. At the time, they seemed like the right choice, but I would rather have 3.73 since my car is still N/A.

Don't worry about 3.73 being too high. You'll be fine.

 

[155dB5.0]

I realy like my 3.55's and would not trade them for 3.73's
only bad think is 55mph is only about 1700rpm i belive, its kind of out of my powerband but its not to bad. In town driving is great


Darren

 

[mustangdaren]

it all depends on the future plans that you may have with the car. Some of my friends get 3.73's or 4.10, then later they add a supercharger and the gears are too much for traction. So they step down to 3.55's or 3.27's.

but if you have an N/A car go with the 3.73's

Good luck

I have 3.73's in my car and its superchargered, love it. It will blow the tires off at 70mph, man what fun. I originally had 3.08s and drove a friends with 3.55 gears, could hardly tell the difference. With the 3.73's it is just right but if you plan on doing any racing you will definitely need some sticky tires.

 

[DirtyD916]

if you had a supercharged 393 , would 3.55 or 3.73 be better.

 

[mustangdaren]

My friend has a Novi 2k supercharged 352 stroker making 22-24 psi of boost, 700rwhp. He has 3.55's in the car. The car runs 10.0's on radials and 9's on slicks with no problems. The car has run mid 8's with a Vortech XX-trim with igloo cooler and the same 3.55 gearing. I couldn't tell you which would be best for a big cube high boost engine but his seems to work fine. I have 3.73's with my 302ci Vortech sc-trim supercharged coupe but I am probably only making near 400 rwhp. It definitely will spin the tires easy in just about any gear but that is what I like, lol. I don't go to the track much, more of a cruiser/show car.

 

[runningmole]

I like my 3.55s