I'm pretty sure the only reason the motor is offset is to clear the steering box/shaft.
That's one of several sound engineering reasons why. Weight bias is even more important, for example - the steering box, battery, brake master/booster, etc. are all on the drivers' side, so offsetting the engine/trans works to re-establish some sort of left-right weight balance.
From what I've read, Chrysler engineers even took into account the weight of the driver!
On my '62 with a 22" radiator, the factory radiator brackets were even made to compensate the position of the engine. The radiator leans in at the top...
We're talking about the horizontal alignment of the drivetrain here; you are correct, however, in noting that the engines do tend to sit in the bay leaned back somewhat. If you remember my thread on doing my own cooling system w/Griffin radiator, the engine lean is quite a bit from top to bottom (like half an inch) BUT that vertical angle doesn't change from side to side.
The engine may be vertically at an angle, but not horizontally.
...and the right side bracket is wider than the left. There's a larger gap on the right side.
Yep, to compensate for the engine/trans being offset to passenger side a couple inches give or take.
The engine isn't parallel with the centerline of the car.
If it is not, it needs to be. Speaking horizontally, the "yoke planes" at either end of the driveshaft (rear of trans, front of diff)
must be parallel but not in direct alignment.
Installing an aftermarket aluminium radiator, I had to fab up some bushings to tilt the top of the radiator inward trying to square the fan blade with it...
Yep, again trying to match the backward "lean" of the engine...
Making up my own exhaust system, I was driving myself crazy trying to make equal length pipes, ect. Finally I threw the tape measure back in the tool box and just cut pipe where it needed to go.
True dat. With the engine sitting to the passenger side a bit, no way the exhaust is exactly equal length from side to side.
So not only is the engine a 1-1/2" off center at the radiator...
Give or take, yep. 1 1/4" - 2" according to models/years.
...but it's also not square with it either. Maybe this was changed in later years with the wider bodies?
Again, it
should be parallel with the body, speaking on the horizontal plane at least.
Now, all of this came in to play when I was putting mine together and I may be misremembering a detail here or there, but let me try this:
1. In the
vertical plane, the driveshaft
needs to approach the diff at an angle for the reasons already stated - wear of components, harmonics/vibration abatement, all that jazz.
Tilting the engine/trans is no doubt done to generate that angle and there is a factory spec on it, I just don't remember what that is. I also assume the pinion is not mounted in the diff parallel to the ground either??
The combination of the two angles gives the final desired vertical pinion angle.
2. In the
horizontal plane, the yoke planes must be parallel but not in direct alignment with each other; both parallel to the car centerline itself.
Hey experts, how am I doing here? Who's got a chassis manual handy?