A project that I've been working on.
The good news is that the Silver Ghost was designed with a mid bearing mounted inside the solid third member and having a two piece drive shaft within. The overdrive unit will just replace the shorter section. Talk about over-designing. The two torque tubes are fastened together with 20 bolts.
GearVender's overdrive unit.
Rear axle out from under with short torque tube removed
The overdrive unit bolted to rear torque tube
The rear axle assembly being raised in place
The overdrive unit bolted up to the transmission's rear universal joint.
Reattach the rear springs, all the brake cables and shock absorbers. All that's left is extending the speedometer cable to reach the rear of the rear housing of the overdrive. RE-route the center bearing lubrication tubing, installing a switch, wiring, and then a test drive...
Most everything went together as planned. The only snafu I encountered was making an adapter so that the speedometer cable could be extended to the Overdrive’s output shaft. That way the speedometer would be reading correctly in or out of overdrive. A number of enthusiasts leave the cable attached to the transmission. Making the speedometer’s readings erroneous when the overdrive is engaged. Anyhow the overdrive functions better than I could have imagined. The engine has plenty of torque so that the car will cruise at Interstate speeds of 65 MPH all day long while the engines turning a tad over 1,500 RPM’s. The RPM was 1,850 without the overdrive.
A little more about the Silver Ghost. Most antique car enthusiasts (pre World War Two) felt that Henry Royce did not start out to make the best car in the world when he designed the Silver Ghost. Rather he just wanted to improve on his older six cylinder to be smoother running and more reliable. He succeeded to produce the most desirable antique car ever produced. Along with being the longest running model car next to the Ford model T.
The 7.4-liter side valve six-cylinder engine is rated at 80 BHP. The seven bearing crankshaft is totally pressure lubricated,, a rarity of its’ time. Along with two head castings with three cylinders each. Each cylinder has two spark plugs. Powered by two distributors. And a precision, quality of a Swiss watch, carburetor that is as reliable as it is beautiful!
Here’s a video of this 84 year old engine idling at 250 RPM’s.