ICE FREQUENTLY ASKED QUESTIONS - GENERAL
Question: What is the benefit of having an ICE ignition system?
Answer: There are several benefits to having an ICE ignition system. These are as follows:
* Easier Starting.
* Better Idle quality (increased manifold vacuum).
* Improved throttle response.
* Improved power and torque (especially low and mid range power).
* Much less chance of detonation due to excessive advance / advance at wrong point on RPM scale.
Question: The CDI system I am comparing to the ICE system has more millijoules than your comparison. Why?
Answer: CDI systems are rated as to how much energy in millijoules they will deliver to the coil primary, not the spark plug as with the ICE system. Unfortunately, not all of this energy reaches the spark plug gap, as a significant amount (can be more than 50%) is lost in the resistance of the coil windings. For any comparison to be fair, the figures quoted have to be under exactly the same test conditions. ICE stands by its test methods and challenges anyone who may doubt them to prove otherwise.
Question: What voltage should I have at the coil positive on my Bosch high energy ignition system?
Answer: As a minimum, you should have alternator voltage (13.8 - 14.8 volts) at the coil positive, to ensure the system operates properly. However, these systems work best with 16 volts at the coil positive, which can be achieved by using a booster (Part No: 2216 or 2316). This will ensure maximum ignition output at all times, even if the voltage feed into the booster drops to 10 volts.
Question: Should I use resistor or non resistor spark plugs?
Answer: In the majority of cases, resistor plugs should not be used (there is only a minority of exceptions to this). Put simply, resistor plugs have approximately 5000 ohms of resistance built into each plug. This is purely for reducing RFI (Radio Frequency Interference). However, it also reduces the energy available to jump the gap in the chamber and increases the probability of cross firing - refer answer below. Even when using higher quality spark plugs with exotic materials for centre electrodes (which increases the energy available at the gap), if they are of the resistor variety, this will offset any gain made by the superior electrode. This situation becomes more critical when using LPG and in high performance engines which invariably have higher cylinder pressures.
Question: Do I need to use a large distributor cap?
Answer: In most cases, a large distributor cap is not necessary. The theory of using large distributor caps, is that it will be harder for the spark to cross fire within the cap, due to the larger distance between the towers. Whilst in isolation, this is true, we must look at what is causing any cross firing to occur. In virtually every situation, there will be a massive resistance in the spark plug lead and / or spark plug (more common when using resistor plugs - refer answer above). The solution to the problem is to rectify any faulty spark plug leads / spark plugs, therefore negating the need for a large distributor cap. By using a large distributor cap and retaining the faulty spark plug lead / spark plug, the problem is only being masked, with the actual fault remaining uncorrected.
