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This handbook is currently under development.
The Ignition Handbook starts with a basic explanation of how a conventional ignition system works then builds from there. The major portion of the book is dedicated to choosing the correct components for your engine, then walking you through the proper way to adjust it for your particular application. Vehicle weight, rear axle gear ratio, engine components, torque converter, transmission and other factors decide what your timing should be through the entire rpm range. Air fuel ratio, engine load and vehicle application are big players, too. You will find a comprehensive data sheet that you can fill out to keep track of your powertrain information and it becomes a handy document to use when requesting technical help. More information is always better than less.
The Ignition Handbook also gets into crank trigger systems, as well as coil on plug and waste spark systems. Through the discussion you should be able to make a good decision on what you might want to select as a system for your application.
The handbook also ties the ignition system to your fuel injection system if you should happen to be running fuel injection.
Here’s a sample;
Ignition Timing Overview
This is rule of thumb information for the typical naturally aspirated street engine. For supercharged, turbocharged, or nitrous fed monsters there is a lot more to it, especially during periods of extreme boost where cylinder pressures are sky high.
Set total timing to 32-34 degrees BTDC @ about 3,000 rpm for an engine with modern parts, like fast burn heads and good fuel control. For older engines or more stock engines you can use as much as 38 degrees of mechanical advance. Use your ears and preferably a knock sensor to make sure you don’t get into a detonation problem.
Adjust the mechanical advance to get a base timing (vacuum advance disconnected and vacuum source plugged) of about 4-6 degrees BTDC at around 600 rpm, or about 10 degrees at 1,000 rpm.
Connect the vacuum advance to manifold vacuum (manifold vacuum is my suggestion, you can use a ported signal if it works best for you) and adjust it (if it’s adjustable) to give about 45 BTDC at idle if you have plenty of manifold vacuum. Also adjust the rate of advance (tension on the diaphragm, usually with an Allen wrench through the vacuum nipple), if you have an adjustable vacuum advance. If you have a big camshaft, or a manual transmission with a lot of gear you may want to forget a vacuum advance altogether. With low and erratic vacuum signals timing will be all over the place, and that’s not going to make for a good running engine.
Note: If you have vacuum present on a ported signal port of your carburetor with the engine at idle you have the throttle plates too far open and need to visit the carburetor section to learn how to correct that situation.
Note: If you are serious about engine set up then your next step is to set the air fuel ratios for your carburetor(s) or fuel injection system. See the section on “Air/Fuel Ratio.”
You’re done!
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