[sd427]

Yes, the swept arc of the needle will likely be the same, not so much the scale, as in 270 deg arc. Smiths chronometric speedos for motorcycles came in 3 inch and 5 inch diameters. The 3 inch went up to 120MPH, while the 5 inch went up to 150MPH, and the same basic mechanism was inside, with different gearing to change the scale.