What do 3.73's Tac at?

[SRT Handz]

I wanna know what 3.73's tac at 80MPH. Right now with stock gears i am at around 2400 at 80 MPH in 5th. Is that right?

 

[ocbaud]

thats about what i have with my stock 3.27 gears, but i believe that the pre99's have a higher gear than that

 

[goshia]

That is about right...

 

[thomas91169]

wtf 2400rpm at 80?

im still only doing 1800rpm in 5th at 80.

- edit -

went to taco bell, on way back checked the above statement.

at 80, i was at 2100rpm. at 85 i was 2350.

 

[Joel's98GT]

you should be about 2700rpm at 80 with 3.73

my 4.10'a rap about 2900-3000 at 80

 

[wms004]

you should be about 2700rpm at 80 with 3.73

my 4.10'a rap about 2900-3000 at 80

That is correct.

I've got 3.73's and a dyno-tune for the speedo.

-Wade

 

['03GTinFLA]

I checked mine this morning and I was at about 2500 at 80mph. But I was driving on the freeway trying to watch the speedo and RPM's without driving into anyone so it could be off a little.

 

[SamMan]

In my auto with 18's and DR's I am at ~2600 @ 75 / ~2800 @80.

 

[hotmustang331]

Ill need t check it out, but mine does 2100 @ 70....about 2400 at 80. I have 3.73s and the TR-3650 with a .62 OD.

 

[jasonh_86]

mine does around 2400-2500 at 80mph with my 3.73's.. TR-3650..

 

[lover]

Kind of hard to tell because there has been tranny swaps and gear swaps from Ford within a few years of each other. I think the 99-01 1/2 are different from the 02s, also the 04s.
I have an 02GT and my fiance has an 04GT. Our 1st and 5th gear ratios are different. That's just a 2 year difference. No telling how many changes were made the previous years.

Just use your onboard digital tachometer. It's a little more accurate than they needle one. But I think that feature is only on the 99-04

 

[ocbaud]

gt ratios:

1999:
axle- 3.27
1 3.37
2 1.99
3 1.33
4 1.00
5 0.67
R 3.22

2000:
axle- 3.27
1 3.37
2 1.99
3 1.33
4 1.00
5 0.67
R 3.22

2001(t45):
axle- 3.27
1 3.37
2 1.99
3 1.33
4 1.00
5 0.67
R 3.22

2001(3650):
axle- 3.27
1 3.37
2 1.99
3 1.33
4 1.00
5 0.67
R 3.22

2002:
axle- 3.27
1 3.37
2 1.99
3 1.33
4 1.00
5 0.67
R 3.22

2003:
axle- 3.27
1 3.37
2 1.99
3 1.33
4 1.00
5 0.62
R 3.22

2004:
axle- 3.55
1 3.35
2 1.99
3 1.33
4 1.00
5 0.62
R 3.22


http://www.mustangmeet.com/specs/2004.php

dont know how correct those are.

i've been using this calculator to see what the speeds should be. http://www.stangsource.com/calculators.cgi?calculator=1

using that, stock everything for my '01 i shoudl be running about 2400rpms @ 84mph

it would be 2600rpms @ 80mph with 3.73 gears

 

[ocbaud]

http://www.svtoa-atlanta.org/cgi-bin/trans.cgi

another good resource

 

[Joel's98GT]

not very correct, the 8.8 is a 3.27

i'm alos not sure about the 3.55 in 04 it's been rumored but i haven't talked to anyone who has them.

the first 4 gears in the t-45 and t-3650 are the same from (96-05) 3.37, 1.99, 1.33, 1.00

but in overdrive the t-45 is .68 and the t-3650 used in the mustang is .62

info directly from tremec: http://www.ttcautomotive.com/English/products/tremec.asp

 

[ocbaud]

as far as i know, my gears are stock(the cover is caked with dirt and doesnt look like its ever been opened up.

My speedo reads at 80mph when my tach is at 2400 rpms.
if we have a .62 5th gear, than it shoudl be reading at 90mph @ 2400 rpm's with stock gears.

if i had 3.73's and a .62 5th gear, it would read exactly 2400 @ 80mph.

 

[ocbaud]

ok, from what i've read is that ford changed the 5th gear to .62 in 2003 to keep with epa standards.

 

[lover]

I thought they changed the 5th gear for better fuel economy. I didn't think the gears were the same for the T45 & 3650. The gearing was changed somewhere after the 01 1/2. But the hell if I know, I read it somewhere.

 

[jasonh_86]

Just buy some 4.10's and call it a day.. that way you know what you got