Weather was really nice today. Probably was over 50 in the sun this afternoon. I installed the drive shaft and changed the rear gear lube.
Here you can see the difference between the steel shaft and the aluminum. The steel is 2.5" thick, the aluminum is 3" thick. They have the same yoke, and are the same length from center to center of the U joints. The aluminum is a 1/4" longer overall because the aluminum lobes are so much thicker than the steel ones.
Got a big surprise from the test drive. The gear noise is much less with an aluminum shaft than steel. Guess the aluminum doesn't transmit or resonate the sound from the gears like a steel shaft does.
The car is nice and smooth and quieter up to about 70, then I got some steering wheel shimmy going on so I think the tires need balancing. At 90 it smoothed out .
Going to have to get the wheels balanced soon.
Can't say if the car is faster or not, but the smooth operation and reduced gear noise is worth it. Any HP gain or faster acceleration is a plus.