#### Druk

##### Gone but not forgotten - RIP

- Joined
- May 28, 2004

- Messages
- 5,300

- Location
- Not far from Edinburgh.

- Car
- 2011 S212 E350CDi. 1981 R107 300TurboDiesel.

Question for the mathematicians out there.

If my car does 3500RPM at 70MPH with a 3.58 diff ratio what would the revs be at the same speed with a 3.07 diff ratio?

If my car does 3500RPM at 70MPH with a 3.58 diff ratio what would the revs be at the same speed with a 3.07 diff ratio?