What gears do i have
02-28-2012, 05:07 PM
#2
one way you can check is to put a mark on your sidewall of your tire, and mark your driveshaft. as you complete one full rotation of the tire, count how many times the driveshaft spins. ex: if it spins 3 1/4 times you have 3.27s, if it spins 3 1/2 times you have 3.55s, 3 3/4 you have 3.73s, 4 times you have 4.10s. or you can take the differential cover off and it will be stamped on the gear.
02-29-2012, 01:50 AM
#3
1st Gear Member
Join Date: Oct 2010
Location: Las Vegas, NV
Posts: 113
You can also try this:
This is a experimental thing, however record your speed and rpm in 4th gear (3rd for an auto) and plug those numbers and your tire size into this "Rear Axle Gear Guesstimator".
This shows the calculations for traveling 50 mph, at 2500 rpm in 4th gear:
Using a GPS recorded speed will be more accurate as it eliminates speedometer error...
This shows the calculations for traveling 50 mph, at 2500 rpm in 4th gear:
Using a GPS recorded speed will be more accurate as it eliminates speedometer error...
02-29-2012, 11:44 AM
#4
TECH SAVANT
Join Date: Dec 2006
Location: Saint Augustine, FL
Posts: 10,938
One caveat in this situation is whether the T-56 was installed with a proper speedometer drive gear--if not the speedometer could be off.
Use my "guesstimator" with speed recorded with a GPS to be sure.
Use my "guesstimator" with speed recorded with a GPS to be sure.
02-29-2012, 10:41 PM
#8
TECH SAVANT
Join Date: Dec 2006
Location: Saint Augustine, FL
Posts: 10,938
The T-56s used in the '03 and '04 Cobra have 0.79:1 and 0.62:1 5th and 6th gears, the so-called "Viper spec" transmission has 0.73:1 and 0.50:1 5th and 6th gears.
Personally unless one is a hard core road racer, or someone who just likes to shift gears, I don't understand the appeal of 6-speed transmission in something with as wide a powerband as even a bolt-on GT. I have driven '03 and '04 Cobras and if I owned one the first thing I'd do would be to put a TKO-600 TCET5008 5-speed in it--but then again I do not sell cars for a living...
02-29-2012, 11:56 PM
#9
Thread Starter
Join Date: Feb 2012
Location: Louisiana
Posts: 19
Im not even sure if i know enough about transmissions and gears to ask correctly. Let me ask this first instead to remove some gray area for me, ok so stock gears are 3.27 with 5 speeds correct? The t-56 has six speeds, and i think i have the 03-04 termi trans. If the prior owner changed the trans to a t56, would he of had to change the gears as well? Because in my head i feel like if the stock gears were kept, the cars 6th gear would have the same ratio as the stocks reverse gear, and i also would not be able to even go into reverse because the stock doesnt have another gear (essentially "7th" gear my reverse)
I apoligize if this seems like a cluttered message, i am just a bit puzzled.
I apoligize if this seems like a cluttered message, i am just a bit puzzled.
03-01-2012, 06:28 AM
#10
TECH SAVANT
Join Date: Dec 2006
Location: Saint Augustine, FL
Posts: 10,938
The transmission and the "gears" (rear end final drive gears) are separate units, one can be changed without changing the other. Your stock transmission had five forward gears and reverse, the T-56 has six forward gears and reverse.
The final drive gears have just a single ratio--3.27:1.
Here's how it all goes together:
The final drive gears have just a single ratio--3.27:1.
Here's how it all goes together: