Timing the cam, the crank, the distributor and other thoughts...


Ok,  we're at the point where it's time to put the engine back together in our Spitfire.  We've gotten the lower end together and the cam sprocket is bolted on and we need to set the cam timing. 

Turn the crank so that the line on the sprocket is pointing up toward the sky.  Turn the cam so the line on the sprocket is pointing down at the ground.  They will form a perfectly straight line between the two of them and the centerline of the crank and the cam.  Another way of saying this is that if you draw an imaginary line from the center of the camshaft down to the center of the crankshaft your imaginary line will also include the two marks on the sprockets.

To put this all in perspective:  The # 1 piston needs to be at top dead center compression (the intake valve has just closed) and your cam/crank sprocket marks need to be in alignment.

Now we need to make sure the ignition timing is in the ballpark.   The Spitfire distributor will only drop into the block in one position cause it's drive tab is offset slightly to one side.  This means that you can't put it in 180 degrees out of time assuming the cam and crank are set up correctly.

Drop the distributor in place.  Make sure it's seated all the way down by turning it's shaft as you drop it in place.  It helps if you sort of 'line it up' so it looks close before you put it into the block. 

With #1 cylinder at TDC compression make sure that you have any one of the plug wire holes in the distributor cap lined up with the rotor.  This will be your #1 spark plug wire.  Remember, this distributor turns counter clockwise so the next wire you want to hook up is #3 and it will go to the left of the #1 plug wire as you look down on the top of the distributor.  Next comes # 4 and after that is # 2.

Let's go for a drive!