The dead giveaway on the difference in the blocks is the poly 318 doesn't have front and rear freeze plugs. Otherwise the dimensions are the same as an LA block. Same block as a 392 hemi?? Please...... The poly 318 was fazed out in early '67 in cars and pickups but in motorhomes.....who knows. The drivetrains were determined by what the coach maker wanted and what was still in stock at Dodge. They went to the 318-3 after that. Not sure it was an improvement actually. The 318-3's had their problems and many parts don't interchange with 318-1's....like those heads. Unless you use the intake and water pump, they won't fit an LA motor.
