Consequences of Excessive Ignition Delay: Potential Damage and Power Loss

Question

Hi,

I have a theoretical question. What will happen (what could happen) if we delay the ignition so much that it becomes a "lag" rather than an "advance".
I suspect it will result in a loss of power, but despite appearances, that's exactly what I'm after. The question is whether there may be any negative effects, e.g. overheating of valves or other damage.
Will ignition take place at all with a very long delay?

best regards,

markslew · Answer

When ignition is too early, knocking combustion occurs, power loss occurs, when ignition is too late, the engine will run softer, but power will drop and fuel consumption will increase.

Overheating of the valves occurs mainly when the mixture is too lean.

dragilla · Answer

But I'm talking about a long delay, let's say 50-60 degrees. I heard a theory that combustion will then take longer (expanded mixture) and may last until the exhaust phase, which in turn may overheat the exhaust valves... Does this make sense?

robokop · Answer

Yes, the mixture will burn out in the exhaust.

kortyleski · Answer

As long as it fires up at all...

vodiczka · Answer

May I know what the purpose of such a delay would be? neither ecological nor economical.

dragilla · Answer

What purpose? Big to write. In the leather - traction control.
Theoretically, this would replace cutting off the spark, which would greatly simplify the system. But I understand that this is not the best solution and it is better to kill the spark than to delay it "to hell"?

robokop · Answer

NO. Better to delay.

Anonymous · Answer

It won't fire at all. It will shoot into the intake or exhaust because the spark will be in the place where the finger is positioned between adjacent contacts.

dragilla · Answer

Can you elaborate? I do it for high-performance vehicles - without a catalytic converter, so it is not a problem for me that the fuel without ignition will be spat out into the exhaust and burn, making a boom In the event of a spark, there is probably nothing else that will threaten me... And if I delay the ignition too much, I can harm the engine, right? Because I realized that I can damage/overheat the valves?

robokop · Answer

And why delay the ignition by as much as 50-60 degrees? A significant loss of power can be noticed even when set to 0. Note that during normal operation of the KWZ engine it can even be over 30 degrees, depending on the engine load. With an on/off spark ignition system, you won't make any money on either exhaust or intake.

dragilla · Answer

And I didn't want to go into the topic... The spark is to be beaten once every Chinese year, when the delay itself is not enough (i.e. when the slippage deepens). So I'm looking for a solution to kill the spark or eliminate its effects. Whipping complicates the arrangement, so I'm asking if I delay it long enough:
a) it won't spoil anything
b) the effect will be the same as killing the spark

best regards,

carrot · Answer

A two-stroke with delayed ignition likes to "rebound" and then rotates in the other direction

In 4T turbocharged sports engines, there are special maps with an ignition delay to maintain the turbine revolutions

Błażej · Answer

Maybe you could expand on this. How is the engine powered - carburetor or injection? Because if this is to limit the engine's power, you can cut off the injectors and the engine will not have problems with the fuel pumped into the exhaust exploding. Cutting off the spark is very simple. There are several ways to do this. Even mechanically.

dragilla · Answer

This is not an option. The question is quite clearly defined: is severely delayed ignition harmful (can it be harmful) to the engine? How much?
Is it better to kill the spark or delay it by such an angle that the ignition will not affect the power (the effect is the same as killing the spark).
We assume that the equipment has an open exhaust and it will not harm the exhaust

Błażej · Answer

But what EXACTLY do you want to achieve and with which engine?

dragilla · Answer

In every engine - it is supposed to be a universal solution. Only that it's petrol. For simplicity, let's assume without a turbine.

Błażej · Answer

Gasine engines do not exist. There is no universal solution for all engines. Depending on the engine generation and the type of power system, this can be done in different ways.

dragilla · Answer

Approx. Sorry for the grammar, I've already corrected it.

Błażej wrote:
...this can be done in different ways.

I don't know what you want to do. I know what I want to do, in fact I'm already doing it. I'm just asking what long-term effects it could have and what would be better, or in other words, what would do less damage - a long delay or killing the spark.

Anonymous · Answer

Both are not good. Lack of ignition, apart from the obvious issue of emitting unburnt fuel particles, causes dynamic fatigue of the crankshaft and the risk of fuel entering the crankcase.

Błażej · Answer

So I'm doing something, but I won't say exactly what, and you tell me if I'm doing something right. If you want help, explain the problem.

Consequences of Excessive Ignition Delay: Potential Damage and Power Loss

Post #1

Post #2

Post #3

Post #4

Post #5

Post #6

Post #7

Post #8

Post #9

Post #10

Post #11

Post #12

Post #13

Post #14

Post #15

Post #16

Post #17

Post #18

Post #19

Post #20

Post #21

Topic summary