Re: 40 amp flywheel?
I didn't do anything for your problem. It's your problem.
I'm assuming the flywheels look the same and you didn't put a 40amp flywheel where a 16 amp was. I'm also assuming that you pulled the flywheel off the crank and not at the flex plate, as most 40 amp flywheels don't have a flex plate.
The magnets that drive the ignition are in the hub part of the flywheel, and their position is critical to timing. Of course if you change the flywheel, you can change the timing. Idle speed is set by timing at fully closed throttle.
In other words, after the change, you need to do a link-n-sync.
hope it helps
John