Hi Atlanta CPR,
Your motor has "left the building". It is on the way to you via UPS.
You will need to purchase a spark plug, as I am out of the short NGK 10 MMM version.
Please understand the original WC-1 spark plug won't fit the upgraded motor, as it was a 14 MM plug and I couldn't make it fit the smaller 10 MM hole, LOL.
One of the modifications I made on your motor was to machine the head to accept the NGK 10 MM .500" reach spark plug. The late WC-1 motors had the smaller 10 MM hole, but used an NGK C7E, as did the later NE head. Bad news is.......the plug is way too long and extended too far into the combustion chamber. This extra long spark plug makes the motor run hotter, and in many cases hits the exhaust valve on motors with the high lift camshaft with a milled head[like yours]. The "rule of thumb" is every exposed spark plug thread can increase the head temperature by 50 degrees [4 threads = 200 degrees]. Many added extra spark plug washers to reduce the amount of threads extended into the combustion chamber, but doesn't transfer the heat correctly to the head. Simply installing a shorter plug in a stock NE head doesn't work, as the threads in the stock head are between sizes. A NGK C7E [.750" reach] is too long, and the NGK C7HSA [.500" reach] is too short.
It is very important you install the correct spark plug, as controlling the heat transfer is most important on Whizzer motors. I will take a few minuites to explain why this is important.
The object is to use a plug hot enough to burn off combustion deposits, yet not over heat the motor. Normally when a motors compression ratio is increased [as in your motor]the plug should be colder, NOT hotter.
Many spark plug companies rate their plugs differently, so be careful. If you want a colder NGK spark plug, the numbers are higher, whereas Champions are the opposite [higher numbers are hotter].
Many select spark plug heat ranges incorectly, and always think hotter is better, NOT TRUE!
A colder spark plug is one that transfers heat rapidly from the firing tip into the engine head, which keeps the firing tip colder. A “hot plug” has a much slower rate of heat transfer, which keeps the firing tip hotter. If you move one complete heat range it can make a difference of 70 to 100 degrees in the combustion chamber. Remember, plug heat range refers to the speed with which the plug can transfer heat from the combustion chamber to the engine head.
You can use the following in your motor.......
NGK C7HSA
Autolite 2795
Champion Z9Y
set the gap at .027"
Have fun,
