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I know some of you are engineers....

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Old 06-20-2005, 03:23 AM
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Default I know some of you are engineers....

Is this a good idea? It'* a replacement front transmission mount. I had the spark while looking at chevy racing mounts for ideas. The peice would be laser cut from steel and bent, then I would cast 80 shore urathane into it.


http://www.damemorder.com/personal/i...nt%20mount.bmp
Thoughts?

The dimensions aren't correct but the concept is there....
Old 06-20-2005, 03:27 AM
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pic no work
Old 06-20-2005, 03:34 AM
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link works.
Old 06-20-2005, 09:35 AM
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I see it ripping out.
Old 06-20-2005, 09:40 AM
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You obviously have to drill holes in the steel for the rubber/poly to flow into, but you also have to determine the load direction. I assume it'* perpendicular to the flat steel faces? If so, you don't have much of a mount. Alot depends on the flex of the material you use, but in reality, there'* a ton of leverage on the rubber material in that design.
Old 06-20-2005, 09:54 AM
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Over time, I think the metal would seperate from the poly.
The trans is going to make the mount rock forward and back(if i'm thinking about it right) and it just looks like this rocking motion and the leverage that bill is talking about will make the metal rip out.
Old 06-20-2005, 10:21 PM
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Umm... how do you figure out the forces at play? How much torque and at what angle?

The cv axles should be the center of the torque... 500ft lbs or so.

12" back from that is a solid rubber mount, so you should obviously figure in the compression of that rubber for the torque angle at the front mount.

the front mount is about 20-22" in front of the cv axle centerline, with the mounting face of the transmission directly over the centerline of the subframe attaching bolts.

On the passenger rear is a dogbone type mount so you have to figure in the rotation of the drivetrain forward as that mount loads along with the compression of the rubber in it.

The forward rotation of the drivetrain due to the PR mount should be minimized due to the design of the torque axis mount.


So, are there some equations I can use to calculate the compression of the rubber and the torque upon the mounts?
Old 06-20-2005, 10:36 PM
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The mounts that aren't on the axis of rotation won't see torque, but rather force. Take the ft*lb torque, divide by feet (or fractions of a foot) from the center of rotation, and you got force.
Old 06-21-2005, 01:22 AM
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Okay, from the fulcrum point of the rear mount to the CV is 7 inches, from the CV to the front mount is 18 inches. If the CV has 500ft. lbs. applied to it, how much lifting force is applied to the front mount and at what angle? Also note that the mounting face of the front mount is one inch higher that the centerline of the CV and rear mount. I assume the wet weight of 375lbs for the drivetrain may apply.
Old 06-21-2005, 09:58 AM
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How high and how far back is the rear mount in relation to the cv?
It'* also going to be hard to use the transmission'* weight because you don't know where the center of gravity is.


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