If the dwell angle is too small, the points gap is too wide and results in poor acceleration or high speed performance.
If the dwell angle is too large, the points gap is too narrow and causes the points to rapidly deteriorate.
I think the recommended dwell is between 49-55 degrees for the 1500 & 1600.
Mine is set at 50 degrees and the points last for a long time and the car reponds well when accelerating.
Thats not a R16 death rattle....its a dried leaf hitting my heater blower fan.