Nu-Rex Nu-Wrench Spark Timing Tool

The Nu-Rex Nu-Wrench is the world's fastest Model A Ford Timing tool and is a 'must have' for any owner.

This tool easily and rapidly sets the standard cam-point and transistor ignition Model A Ford spark ignition timing. It requires no judgement in its use.  Abbreviated instructions are on the tool, but more detailed instructions are as followed:

It is desirable to assume full spark timing range- start, idle and maximum engine RPM advance.

  1. Move the steering column lever full 'Up' to full ' Down'. The edges of the upper pint plate control arm should just contact first one side of the opening and then the other (one inch total) of the distributor. This is 40 degrees timing range at the crankshaft.  A range of approximately 34 degrees is all the engine can use.  If that arm travel/range is less the steering column needs to be adjusted. The column clamping bolts should be loosened and then the column can be rotated to attain the desired range.
  2. Adjust the point gap to 0.020 plus or minus 0.002 inches, transistor ignition pick-up trigger gap should be set per kit instructions (usually 0.003 inches).
  3. Set the steering column spark control lever full 'Up'. This sets initial spark timing for zero degrees/Top Dead Center (TDC) for start/idle.
  4. Remove the Timing Case 'Timing Pin' - insert the rounded end into the case cover. Hand-crank the engine so the 'Pin' centers into the dimple on the engine camshaft gear. This is TDC on cylinder #1.
  5. Remove the distributor cap and rotor. Place Nu-Wrench on the point cam or transistor pick-up trigger wheel (reluctor): loosen the cam or trigger wheel hold-down screw for a slight drag on the wrench rotation and rotate the wrench clockwise. This removes distributor shaft drive train slack.
  6. Rotate the Timing Tool two (2) turns clockwise. STOP when the tool leading edge (Δ) contacts the #4 rearmost distributor pin. Hold the pin and tighten the cam or trigger wheel screw. This concludes adjustment.
  7. Reinstall the rotor and distributor cap.

For other specific timing settings and measurement, it is recommended that the Nu-Rex Precision Timing Kit be used.

An optional timing setting involves 'retard' for ease in start up conditions and a slower idle speed. Substitute step #3 as follows:

Set the steering column spark lever one (1) or two (2) detent clicks down. This sets the spark timing at 4 degrees or 8 degrees crankshaft retard (each click is 4 degrees). Continue with the remaining instructions above.

Any questions contact us or call 330-784-5334.