diff gears

[bigred86]

hey everybody, I am in the process of building a diff for my commodore. Cammed Vx v6 with a getrag 5 speed I’m putting a tru trac in it with new bearings I’m stuck on what diff gears to choose from. I was just wondering if somebody could answer a couple questions for me with this motor and box combo
RPM @100kph with 3:46
RPM @100kph with 3:73
RPM @100kph with 3:9
RPM @100kph with 4:11

 

[Immortality]

Check out this thread.

https://forums.justcommodores.com.au/threads/driveline-gearing-rpm-calculator.289716/

 

[gtrboyy]

As above there are online calculators to work out rpm.


Other factors to consider how often will it be on highway...if not much then go shorter & there is always 5th gear to use.


Shorter gears will make it easier to drive around if has big cam.

.3.46 not much of a step up from 3.07 might as well find cheap v8 manual diff to put in it & see if too tall then sell off again.

3,7 would be tallest I'd put in a car if paying money.