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Iridium spark plugs are a real benefit for a gasoline engine.

Иридиевые свечи зажигания

Cold and snow, as we know, we always come completely unexpectedly. Moreover, not only for city services, but also for motorists too. The owners of gasoline cars are well aware of the importance of such a small detail as a spark plug. Especially in winter. The only spark between its electrodes affects whether the car starts in a frost or not.

Today we will talk about a fairly new product on the market of auto parts - iridium spark plugs, try to figure out what it is - the last squeak of candle fashion or the real benefits for a gasoline engine?

Modern spark plugs in their ideology and design are not much different from those that were half a century ago. The differences lie in the details. Designers spark plugs work within the technological triangle: increase the service life of the spark plugs, improving the reliability of ignition and more complete combustion of the fuel - air mixture. The result is fuel economy, exhaust cleanliness and an extended spark plug interval.

Candle's ability to stably and reliably ignite the fuel - the air mixture can be increased by increasing the spark gap (distance between electrodes), or by reducing the diameter of the central electrode due to the use of refractory and chemically resistant noble metals in its manufacture. But a large spark gap leads to an increase in the required voltage for the occurrence of a spark, and the use of refractory metals increases the cost of the candle. Spark plug developers follow two paths to meet the demand of various categories of customers.

Thus, in standard nickel alloy spark plugs from the leading manufacturers of candles from DENSO and NGK, a U-groove on the side electrode (DENSO) and a V-shaped kerf on the central electrode (NGK) appeared. Both technologies make it possible to achieve a common goal - to increase the gap between the electrodes and shift the spark and the ignition core to the open space of the combustion chamber without the use of precious metals.
The use of iridium alloy for the manufacture of candle electrodes reduces the diameter of the central electrode to 0.7-0.4 mm in different models compared to 2.5 mm in nickel candles, due to the high melting point, mechanical strength and chemical resistance of iridium.
Иридиевые свечи зажигания

What gives us a thin iridium electrode?

The small diameter of the central electrode and the bevelled edges of the side electrode make it possible to obtain a powerful spark, since less voltage is required to break the interelectrode gap, and the ignition process is also significantly improved, because the suppressive influence of the electrodes on the propagation of the flame front in the combustion chamber is reduced.

Hence a number of advantages:

  • Increased engine power;
  • Reduced fuel consumption;
  • Decrease in toxicity of "exhaust";
  • Soft start of the engine even in a hard frost.

In addition, refractoriness of iridium significantly increases the resource of such a candle.

When comparing the work of standard, platinum and iridium spark plugs on the test bench, the following was revealed: Everything is as usual on an ordinary candle. Sparks are torn around the gap, and their color is different - from pink to bright blue. When the platinum candle is working, no individual sparks are visible, they all merged. Candles with a thin iridium electrode during operation give a clear stable white cone. The color of the spark, by the way, in itself speaks volumes. Red or pink spark - a weak, often giving a skip flashes. Blue, blue - more intense, and white - the most stable and hot. All iridium candles with thin electrodes give just such a spark. It speaks about their reliability in the complicated operating conditions, which in real life can be mass. This includes a cold start of the engine, and a discharged battery, and at the same time included powerful sources of energy consumption in the car, which “land” the voltage in the onboard network.

Fuel consumption on an engine with injection iridium spark plugs with a thin central electrode can be reduced by 6-7% compared to standard candles. The influence of iridium spark plugs on gasoline consumption on carburetor engines is not so noticeable: no more than 2%. In general, there is a pattern: the thinner the central electrode, the less fuel consumes the motor.

Although not much, by 3-4%, but the engine power on iridium candles is growing compared to the standard ones.

So are “precious” candles worth their money? Let's count.

A standard NGK spark plug on a Carina car, engine 5A-FE, BKR5EYA-11 costs 139 rubles. Iridium candle BKR5EIX-11 costs 599 rubles. The difference in the cost of a set of candles is 1840 rubles. Let 95 gasoline consumption per week is 50 liters. This is about 1350 rubles. The reduction in fuel consumption on iridium candles is 6-7%. This is 95 rubles a week. Total, to pay off the candles, you need to travel for 5 months. These candles live almost the entire life of the car from one owner. Improved dynamics, increased reliability, reduced exhaust emissions and a long service life of the exhaust catalyst are already additional bonuses.

How to be the owners of cars with carburetor engines? Of course, choosing candles, you need to be guided not only by the required characteristics, but also by common sense. Yes, the "ruble" benefit in this case will be less noticeable, although all the other "pluses" of the "precious" candles will not go anywhere.

And here is another argument: The use of iridium candles is uniquely justified on motors, which have difficulty in accessing the candles and in which only the replacement of candles will cost almost more than their cost.

Of course, the choice of iridium spark plugs is a choice in favor of comfortable driving and gentle operation of the car.

By the way, iridium spark plugs can work on any gasoline (meaning its quality), since they are rather inert with respect to additives. But in order to reduce the effect of low-quality gasoline on the service life of candles, we recommend that you fill the car with fuel only at proven gas stations, where you are guaranteed not to flood diesel fuel instead of 95th gasoline!