AMC Harmonic Vibration Damper Listing

For reference, each damper was individually balanced to each crank. The drilled holes were part of the balancing process.

Vibration Damper Listing

'67-'69 290: #3180477
'70-'71 304: #3196924
'72+ 304: #3216083
'67-'69 343: #3181612
'70-'71 360: #3196925
'72+ 360: #3230131
'68-'69 390: #31916189
'70 390: #3196925 (same part number as a '70 360 but balanced differently at engine assembly)
'71 401: #3211454 3-bolt(this is according to old info. I have one with no numbers at all on it)
'7? 401: #3211454 4-bolt
'73/4 401: #3216085 4-bolt

290 Vibration Dampers.  The one on the left is 1966 only.  The one on the right is 1967-69

290 Damper on the left, '67-'69 343 on the right (Note no cut out in the weight pad)

'68-'69 390 Vibration damper on the left, 1970 390 Vibration Damper on the right.  The off-set weight goes 180 degrees on the 1968-1969 390. The off-set weight goes 240 degrees on a 1970 390  ( all are 3-bolt)

1973 and latter 4 bolt Dampers.  304, 360, 401.  The off-set weight goes 90 degrees around on a 304 (both 3&4 bolt)   The off-set weight goes 240 degrees around on a 360 (both 3 & 4 bolt)   The off-set weight goes 180 degrees on a 1971-1972 401. (3-bolt)    The Off-set weight goes 240 degrees on a 1973 and latter 401 (4-bolt)