Vibration and Driveline Angles (trans & pinion) question

[ericj205]

Here is a sketch I borrowed from another board…

 

[biker]

I used Belltech kit #4977 x 2 from Amazon. I wanted the long center pin bolts and coupler nuts. I ordered 2 kits (4 wedges) because of the design of the 12 bolt spring perches. I need to add a second wedge equal and opposite of the first wedge on the under side of the leaf spring so the shock mounting plates bolt up square to the axle spring perch. I drilled out a 3/8 nut to slide over the center pin bolt to act as a spacer. This allows the head of the center pin to protrude past the top aluminum wedge and act as a “locator” in the axle as originally designed.

Ok thanks. Nice work.

 

[ericj205]

I did some more inspection and measurements. The rearmost section of the subframe is centered under the car based on the same distance from exterior of sub frame to the main body welded seams.

 

[ericj205]

Carb pad was more or less level with the car...

 

[ericj205]

However, I did remember when I did a "frame-off" poor mans restoration long ago I replaced the OEM subframe bushings back in 2000 that I used the aluminum style 1/2" replacements. When we fitted the front end sheet metal we noticed it fit and looked better without the bushings under the radiator support. So instead of the 1/2" bushing we used thick rubber pads. I could also see the affect of this on the position of the fan in the shroud. Small gap at top, large gap at bottom.

In hindsight that could account for the steeper than normal angle of the motor trans "down" as it extends to the rear of the car. I guess I could loosen the subframe, put the 1/2" spacers under the radiator mounts, appropriate large washer shims in the "mid" mounting points and leave the rear subframe bushings as is. That could maybe reduce my angle down by 1/2 degree or more...

 

[jbloake]

Definitely should have the proper size bushing in there ! But did it actually change your angle?

 

[ericj205]

I have not decided if I will attempt that yet. But it should change the angle of the motor/trans if I add a 1/4” spacer to the bushings in the center section of the subframe and 1/2” bushing under core support and leave the rear most bushings as is.