I have a 1984 43' Californian trawler and just had my props done with Wolverine Propeller in Michigan*and they did "Prop Scan". This is the best thing I have ever done! My*Californian now cruises at 17MPH and reached a speed of 23 MPH on my GPS*last weekend with NO vibration at all. The cost was high ($600) but well worth it.*I don't have fuel consumption gauges but noticed that I did not burn as much*fuel as normal on*my*94 mile round*trip. (gas 454's)*