1964 driveline angle

[Brian Taylor]

Hi folks. This is my first post on this forum, and it's a question for my dad who recently bought a 1964 hardtop. He's doing some cleaning up of the engine compartment, and with the hood off, he noticed the driveline of the car, from engine to rear diff, is at a slight angle instead of being parallel to the frame rails. Is this normal? I'm sorry I don't have a pic to explain it better, but basically if you were looking at just the chassis with the driveline installed from a bird's eye view, the line from the engine to the rear diff. would be at a slight angle to the frame. Does that make sense? Any help would be appreciated.

Brian Taylor

[Joe Lucia (12484)]

Re: 1964 driveline angle

Brian-----

Yes, it makes complete sense and that's exactly how it is. The engine in a Corvette is not centered between the frame rails; it's offset slightly to one side. That means the centerline of the engine and transmission is offset, too. The differential assembly is centered between the frame rails. So, there is a slight difference in the centerline between the transmission output shaft and the differential input shaft. That difference is taken up in the universal joints and that's what causes the "phenomenon" you're describing.

[Wayne Midkiff (3437)]

check thread on this subject Jan 28th/29th

with picture of frame dimensions, showing offset.

[Michael Hanson (4067)]

Re: 1964 driveline angle

Joe,

Your description of the engine/transmission offset is absolutely correct. The drive shaft, however, continues on it's "off center" journey all the way back to the diff and connects to the pinion, which is also off the C/L of the chassis. I don't remember the actual spec on this but I believe the engine, transmission, drive shaft and pinion C/L were nearly 1.0", or more, to the right of the frame C/L.

[Joe Lucia (12484)]

Re: 1964 driveline angle

Michael-----

Yes, you're correct on that. The offset from centerline is "corrected" by the corresponding and opposite offset built into the differential housing.

[Louis Trohatos (40341)]

Re: 1964 driveline angle

I seem to recall reading somewhere that the engine and transmission were placed a bit to the right of centerline to better balance the car with the driver as the only occupant (presumably there'd be no passenger in situations requiring maximum performance), and to give the driver a bit more legroom (at the expense of the passenger, of course). The weight shift to the right follows the same logic of hotrodders who, when wanting to shift weight to the rear, used to relocate the battery to the right side of the trunk, regardless of its former orientation in the engine compartment.

[Duke Williams (22045)]

Re: 1964 driveline angle

The other thing to remember is that if the U-joint angles are zero, the joint won't last because all the load would be concentrated at one point all the time. A slight angle causes the trunnions to rotate back and forth slightly relative to the cups which distributes the load over a larger area, so you always want some minimal angle to generate at least a little joint movement.

Duke