VY 2004 LS1 Crewman Differential

[losh1971]

I think the ideal is to have top gear revving at about 2000-2100 at 100kph. This gives good take off and is good for economy.

 

[Immortality]

In the drive line section there is a thread with a link to a online calculator that allows you to play with diff ratios and see what changes it makes.

 

[Stephen Bartlett]

3.9 might be too short still if four speed auto. @Immortality would likely know for sure. 3.7 might be the ideal with a 4L60e.

Yes it’s a 4 speed auto.