3:01 diff ratio?

[Illoshday]

A mate told me I should get a 3:01 diff ratio for my VT as he reckons it’s a good ratio for drifts, what’s the pros and cons

 

[vr304]

Do you mean 3.91?

 

[Illoshday]

Do you mean 3.91?

Yes it was a typo, what’s the revs like on the motorways with a 3.91 diff ratio

 

[vr304]

Depends also if auto or manual v6 or v8?

 

[Immortality]

There are online calculators to help you work out what is what. OR see

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

 

[Illoshday]

Depends also if auto or manual v6 or v8?

Auto V6 am doing a manual swap before changing the diff tho

 

[vr304]

Either 3.7 or 3.9 will make a big difference in pickup etc

 

[rambunctious]

Either 3.7 or 3.9 will make a big difference in pickup etc

It will rev higher and speedo will be incorrect by approx 27% on a 3.9 assuming present diff is 3.08.
edited for correct %

 

[vr304]

It will rev higher and speedo will be incorrect by approx 27% on a 3.9 assuming present diff is 3.08.
edited for correct %

Yip done diff ratio changes on my previous commodore so aware of that, not sure how you go about doing speedo correction on vt v6 but on my old vx ss the tuner was able to adjust it via the ecu

 

[Lex]

Yip done diff ratio changes on my previous commodore so aware of that, not sure how you go about doing speedo correction on vt v6 but on my old vx ss the tuner was able to adjust it via the ecu

Scanner to change the pulse count in the cluster.