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Alt 08.04.2011, 08:43
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Tom.Schmeler
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Registriert seit: 13.05.2009
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Vorname: Tom
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AW: R32 Turbo Zuendkerzen !

Es geht ganz einfach da drum, dass die OEM Kerze mit dem Gap wie sie aus der Kiste kommt je nach LD zum "foulen" neigt und dies zum "klopfen" und Fehlzuendungen fuehrt.
Desweiteren sind unsere Turbotemperaturen hoeher als bei einem Sauger.
Daher sollte schon am besten eine Kerze genutzt werden die die aufgenommene Temperatur aus dem Brennraum besser an den Kopf abgeben kann.
Last but not least geht es noch um Funkenstaerke und Lebensdauer.

Da stellt sich schon die Frage, welcher Hitzegrad, welche Bauform, welches Metall, booster gap oder nicht.

Das Thema ist bei Tubo an sich schon wichtig. Daher wuerde mich mal dringends interessieren wenn wie HGP oder BTS die OEM Kerzen beutzt werden, sie auch das Gap verkleinern von 0.9mm auf +-0.75 und evtl weniger. Selbst NGK sagt dass bei aufgeladenen Motoren das Gap definitv um die 0.7mm liegen soll, durch die hoeheren Druecke im Brennraum.


Hier mal NGK zum Thema, die gehen sogar soweit und sagen pro 100ps mehr eine Kerze mit einem Grad hoeher also bei underen Turbo dann schon eine 9er Kerze.







note:You might not be able to get our products in your country.
Choose the right spark plug for your engine based on heat range and electrode design, engine tuning, and racing conditions.
Heat range
Electrode design

Spark plugs with a higher heat-range number have superior cooling characteristics. Engine tuning Torturous racing conditions Avoid problems due to extremes of temperature

Low-speed performance
Racing plugs for both two- and four-wheel vehicles have been developed and designed for use in engines that have been fine-tuned to achieve maximum power under specific racing conditions. Racing plugs differ from standard plugs, both in appearance and performance, and often sacrifice plug life, and efficiency at low-speeds for optimum performance and durability under torturous racing conditions.
What to look for when choosing a racing plug


Shell desigh - To determine what kind of shell design fits in your engine, check the serial number of regulation plugs or the plugs you are currently using to verify the thread diameter, pitch, thread length and shell seat.
Firing End design - Refer to the section below on electrode design to determine which type is best for your needs.
Heat range - It's important to choose a racing plug with a heat range that keeps the electrode at an optimum temperature under even the most torturous racing conditions. And remember : A higher heat-range number does not improve engine performance, it increases the plug's ability to dissipate heat.
Resistors - Due to advances in ignition-system technology, there is little if any difference in performance between plugs with resistors and those without. However there are still some variations of some models that require plugs with resistors to avoid engine trouble.

Choosing a firing end design
Although a good rule of thumb is that the more an electrode projects into the cylinder, the better ignition it provides, it's also true that longer projections are more susceptible to the wear and tear of extreme temperatures. High-power, high-performance engines, of course, not only run hotter, thex also vibrate more, which is why we recommend choosing a firinig end design that reduces exposure of the electrode and insulator as much as possible.
Projected type
Quite similar to a standard spark plug electrode, these plugs give good overall performance in lightly tuned and naturally aspirated engines, as well as good performance in the low to medium turque range in turbo engines.

Angled ground strap
These provide superior performance in turbocharged engines with power boosts of 50% or more. The short ground electrode is also highly durable against mechanical shock.


Semi-surface discharge
In a sense, this is the ultimate plug configuration. Nearly all insulator cracking and electrode melting can be prevented with this type.
Nevertheless, service life and low-speed performance may suffer slightly.
Once you've found a plug that matches your needs, give it a try and feel the exhilaration of getting 120% performance from your engine.


NB: We highly suggest having read and thoroughly understood the information in the prior sections Operating Temperature, Heat Range, Projection and Electrode Gap in relation to Modified / Performance Engines.
It is critical to note that once an ENGINE IS MODIFIED, THE RECOMMENDED SPARK PLUG listed in the NGK Spark Plug catalogue for that application MAY NO LONGER BE SUITABLE.
When an engine is designed by a vehicle manufacturer, thousands of hours of testing and design are dedicated to ensure that each engine component will operate to satisfaction across a variety of engine and environmental conditions. Any engine modification in effect alters the engine characteristics and as such, it is the end users responsibility to ensure that every engine component that may be affected, is considered and redesigned if necessary.
(Once an engine is modified the engine’s characteristics are changed and as such each engine component affected by the modification needs to be considered and appropriately re-engineered.)
Example If a V8 engine was fitted to a 4 Cyl. application, the transmission would most likely fail due to the higher power output of the V8. In this instance it would be unreasonable to blame the transmission manufacturer claiming the transmission was at fault. Similarly, if an engine is modified, the spark plug needs to be appropriately changed as the standard spark plug may no longer be suitable due to the different characteristics of the engine.
The two major factors that need to be considered when an engine is modified:
  • Heat range
  • Electrode gap
HEAT RANGE

The most critical factor for a spark plug that needs to be considered when an engine is modified is HEAT RANGE. Spark plugs are designed to operate in a temperature range of 450 – 870°C, when an engine is modified (generally to produce more power which produces more heat) in turn the engine and subsequent spark plug temperatures increase. Depending on the modification will depend on the change in temperature profile.
It is not possible for NGK to provide a recommendation for a modified engine. For NGK to make a recommendation, the spark plug needs to be tested and certified for that engine. The list for modifications and variations is endless and as such making a recommendation is not possible. NGK will happily suggest a spark plug however due to the infinite options for modification, the onus is on the customer to test and ensure that each engine component is suitable based on the specific modifications performed.
Example Take two identical vehicles for example a Ford 4.0L I6 Falcon. One customer may modify the engine with a turbocharger and exhaust, whilst a second customer may use a bigger turbocharger and different exhaust, on paper the engines have similar modification however the engine characteristics may differ greatly. Quantifying the extent is very difficult without performing extensive testing. As such it is the end users responsibility to perform some testing.
CHOOSING A PLUG:
When selecting a spark plug for a modified engine it may be difficult to initially gauge the heat range. A very expensive heat range test can be performed however a more viable option is to start with a colder heat range spark plug and perform some testing. As mentioned a spark plug operates in the range temperature 450 – 870°C, at 450°C carbon deposits being to burn off and if a plug may have a very black insulator nose at a lower temperature. At 870°C a spark plug will have a very white insulator nose which will blister if this temperature is exceeded and the ground electrode will melt.
Example Take a Holden engine which as standard uses a BPR 5ES spark plug. (The heat range for this spark plug is 5, please refer to our part number identification for further information) If a customer were to install a turbocharger, intercooler and exhaust system to this vehicle, it would be suggested to start with a spark plug with a 7 heat range (BPR 7ES) to be on the safe side. The customer would then need to perform some road testing,
  • firstly applying half throttle
  • then inspecting the plugs,
  • ¾ throttle then again inspecting the plugs
  • and eventually full throttle.
At any stage of inspection if the plugs upon removal are very clean and white along the insulator nose this would indicate that the spark plugs are reaching their upper temperature threshold and as such obviously may not withstanding the temperature at full throttle. Fouling a set of spark plugs is very cheap compared to the cost of the engine modifications performed and insignificant compared to the amount of research and design that goes into producing the engine by a vehicle manufacturer.
Using "racing" spark plugs

Be cautious! In reality, most "racing" spark plugs are just colder heat ranges of the street versions of the spark plug. They don't provide any more voltage to the spark plug tip! Their internal construction is no different (in NGK's case, as all of our spark plugs must conform to the same level of quality controls) than most standard spark plugs.

NGK as a company tries to stay clear of saying that a racing spark plug (or ANY spark plug) will give you large gains in horsepower. While certain spark plugs are better suited to certain applications (and we're happy to counsel you in the right direction) we try to tell people that are looking to "screw in" some cheap horsepower that, in most cases, spark plugs are not the answer.

To be blunt, when experienced tuners build race motors, they select their spark plugs for different reasons: to remove heat more efficiently, provide sufficient spark to completely light all the air/fuel mixture, to survive the added stresses placed upon a high performance engine's spark plugs, and to achieve optimum piston-to-plug clearance.
Some of these "specialised racing plugs" are made with precious metal alloy centre/ground electrodes or fine wire tips or retracted-nose insulators. Again, these features do not necessarily mean that the spark plug will allow the engine to make more power, but these features are what allow the spark plug to survive in these tortuous conditions. Most racers know screwing in a new set of spark plugs will not magically "unlock" hidden horsepower.
Many of the more popular aftermarket ignition systems are of the capacitive discharge type. They store voltage, or accumulate it, until a point at which a trigger signal allows release of this more powerful spark. Companies like Mallory, MSD, Crane and Accel, to name a few, offer such systems.
They affect spark plugs in that they allow the gaps to be opened up to take advantage of the increased capacity. The theory is that the larger and the more intense the spark you are able to present to the air/fuel mixture, the more likely you will be to burn more fuel, and hence the more power you will make.
We encourage the use of such systems, but only on modified or older non-computer controlled vehicles.
In reality, computer controlled vehicles do such a good job of lighting off the air/fuel mixture (as evidenced by the ultra-low emissions), added ignition capacity would do little to burn more fuel since the stock configuration is doing such a good job. Older non-computer controlled vehicles or those that have been modified with higher compression or boosted (nitrous, turbo, supercharged) engines can certainly take advantage of a more powerful ignition system.
With modified engines (those engines that have increased their compression) more heat is a by-product of the added power that normally comes with increased compression. In short, select one heat range colder for every 75-100 hp you add, or when you significantly raise compression. Also remember to retard the timing a little and to increase fuel enrichment and octane. These tips are critical when adding forced induction (turbos, superchargers or nitrous kits), and failure to address ALL of these areas will virtually guarantee engine damage.
An engine that has poor oil control can sometimes mask the symptom temporarily by running a slightly hotter spark plug. While this is a "band-aid" approach, it is one of the only examples of when and why one would select a hotter spark plug.

Gap

Modified engines with higher compression or forced induction will typically require smaller electrode gap settings (to ensure ignitability in these denser air/fuel mixtures) as the voltage requirement at the electrode gap is increased due to higher combustion pressures. As a rule, the more power you are making, the smaller the gap you will need.
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