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Just Some Dude in Jersey
14,885 Posts
Discussion Starter #1
As part of my Motronic FI install in my GT, I had to install 1/2" shorter motor mounts to prevent the FI manifold from hitting the cowling on my GT. But now I have the problem of the crank position sensor touching hard against the front suspension cross member, about 4" off center towards the passenger side. If I lift the engine and slip 1/4" of shims between the passenger side motor mount and the engine's motor mount ear I might be able to fix the problem. But then I'm tilting the engine towards the driver's side and this may cause a fan/shroud misalignment and maybe even make the FI manifold touch the hood or the cowling. Maybe.

So, it occurs to me to lower the tranny 1/2", which should cause the engine to teeter-totter on the engine mounts and lift up in the front and stop the CPS from touching the cross member. I have reason to believe that my auto tranny is sitting too high. If you've ever seen a GT with an automatic and the original rubber tranny mount, you will have noticed that the mount is always crushed flat. It's a very weak, soft, spongy, rubber mount with a "window" cut in it. So, I now have a replacement one from one of our suppliers and it is rock hard dense rubber that doesn't compress at all under the weight of the tranny. Compared to a typical GT's oem auto tranny mount, it's possible that the output end of my tranny is a full inch or more higher than oem. Possibly. I have no idea what height the driveline should be at various points.

Which leads me to wonder where should the centerline of my drive train be at various points?

If measured from the ground, should the center of the crankshaft at the front pulley be the same height as the output of my tranny and the center of the torque tube and the center of where the driveshaft enters the rear axle?

Would this be the way to measure alignment of the drive train?

Is the drivetrain dead straight like that and remain the same height off the ground from front pulley to rear axle or does the whole drive train angle upwards a bit. Yes, I know that the rear axle goes up and down. Presumably, at rest, maybe with a driver in the car, the driveshaft is in a perfect straight line and parallel with the engine's crankshaft.

How important is it to have perfect alignment?

How much can I be tilted/raised/lowered one way or the other at various points and not cause a problem?
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