pa karp said

I have been chasing two vibrations in my 340 1969 'Cuda. I got the drive shaft issue taken care of, new drive shaft from a supplier that knew what they were doing.

There is a 2nd issue. I have a vibration at 3000 rpm, aproximately 65 mph. When I kick in the clutch, let the engine go to idle, or shut the engine off, and shift the trans into neutral the vibration goes away. No vibration what so ever, clutch in or out.

I have checked the flywheel and dampner, both are neutral balance because of the forged crank. The engine has been balanced by my reputable engine builder.

Where this gets really interesting, with the engine at idle or shut off, when i depress the clutch and shift the trans into 4th the vibration returns! I do not engage the clutch. When I shift the trans into neutral, the vibration stays, whether the engine is at idle or shut off. I repeat the process, vibration disappears as soon as I shift into neutral. But if I shift back into 4th, clutch depressed, the vibration is back.

What should I be looking for here? Is this a possible bushing issue in the trans tail shaft?

Thanks

Curt Rees

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pa karp said

Vibration is gone! After more money, oh well.

I was able get to a drag strip, KRP in NE since Oahe had closed for the season. I made 4 passes in the 14's, the best at 14:74. Since KRP is at 2100 feet, with the factor that would be a 14:50.

That was my goal all year. 14:50's is what it ran in 1969.:burnout:

Curt Rees

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