[yatinchoubal]

Originally Posted by Raccoon

All in all, these extra electrode thingies are one more marketing ploy. But the good thing is that they probably wont do any harm in most engines either.

No, I dont think so.. and trust me Im not saying this, just coz I have bought it. The instant thing, I noticed, when i first plugged them in, is during the start of the car. The car starts more quicker, and I dont even need to turn the key, as i required to, earlier. Although, this is a minor difference, I noticed more better flow, of electricity. I did a comparison with my stock plugs and the four electrode ones.
4 electrode plugs, do make some considerable difference. but the best result is achieved when you need to change the wires too..

My observation was a better pick up in my ride, than previous

[Raccoon]

^^^You probably find that difference because you might be comparing their effect on your car after changing old worn plugs. Compare them with a good single electrode plug with the gap precisely set. There is no scientific evidence to show that more electrodes are benificial. One good spark with one ground electrode is as good as anything else.

Btw, whats the cost of an equivalent normal sparky? Just wanted to know the cost difference between the two...

[SS-Traveller]

Originally Posted by Raccoon

^^^You probably find that difference because you might be comparing their effect on your car after changing old worn plugs. Compare them with a good single electrode plug with the gap precisely set. There is no scientific evidence to show that more electrodes are benificial. One good spark with one ground electrode is as good as anything else.

Btw, whats the cost of an equivalent normal sparky? Just wanted to know the cost difference between the two...

I agree. A brand new single-electrode spark plug costing @ Rs.60-80 will not have any remarkable difference in performance compared to a multi-electrode spark plug costing 4-5 times more, in most vehicles we use in India. on the other hand, I would trust the quality of a single-electrode plug with warranty procured from a good shop more than I would a fancy imported set without warranty from a shop I don't know.

@ sgiitk: Congrats! You clean plugs and set gaps AND keep a couple of spares in the car - "old school" like me! The newer cars don't even provide plug spanners in the tool kit like they used to. And a lot of cars (the Swift for example) have the plugs set so far inside, an extra-long spanner is required to unscrew them. BTW, have you seen a spark plug sand-blaster in Kanpur lately? I can't find one in Delhi.

[Harshavarthan]

Just read the manual. Hyundai recommends Spark Plug replacement every 30000 kms for santro. I have done 28000 in my car without replacing it and so far no complaints.

[adi99]

Originally Posted by Raccoon

^^^You probably find that difference because you might be comparing their effect on your car after changing old worn plugs. Compare them with a good single electrode plug with the gap precisely set. There is no scientific evidence to show that more electrodes are benificial. One good spark with one ground electrode is as good as anything else.

Btw, whats the cost of an equivalent normal sparky? Just wanted to know the cost difference between the two...

You are right. I changed the plugs to denso/denzo, not sure! Now the pick up and running is much better. I guess I was running worn plugs before!

[vivekiny2k]

Originally Posted by yatinchoubal

The instant thing, I noticed, when i first plugged them in, is during the start of the car. The car starts more quicker, and I dont even need to turn the key, as i required to, earlier.

dude, get rid of that plug. this sounds like a hazard to me.

[R2D2]

Originally Posted by SS-Traveller

When durability is the watchword in car parts, why have spark plugs (and expensive ones at that) chucked out at 10-20k km? I remember our Amby plugs could last over 40k km, with a routine cleanup and gap reset every 10k km. Somehow, somewhere, did we take a big leap backwards in spark plug technology?

Can anyone please post more technical information on the need to replace plugs so frequently? And have we actually stopped cleaning and re-gapping plugs?

It all depends on the type of spark plug and car mfr. In the US, the 9G and 10G Corollas come with Denso/NGK iridium spark plugs that can go for 100,000 miles (160k kms) without changes. Yes, that's not a typo.

Plug mfrs set the gap at the factory (to 1 - 1.1 mm as most CDI systems require that gap) do not recommend either sanding the plug or resetting the gap once the SP is in use. The plugs are to be replaced. I think the main reason is that people damage the negative electrode when setting the gap as most use screw drivers, not gap setting tools.

A set of 4 normal mfr recommended plugs costs about Rs 600-1000 on an average for a normal car and require replacement every 20K to 40K. I dont think its a heavy expense to bear.

Rgds,

R2D2

[SS-Traveller]

Originally Posted by R2D2

Corollas come with Denso/NGK iridium spark plugs that can go for 100,000 miles (160k kms) without changes. Yes, that's not a typo.

Plug mfrs ... do not recommend either sanding the plug or resetting the gap once the SP is in use. The plugs are to be replaced. I think the main reason is that people damage the negative electrode when setting the gap as most use screw drivers, not gap setting tools.

A set of 4 normal mfr recommended plugs costs about Rs 600-1000 on an average for a normal car and require replacement every 20K to 40K. I dont think its a heavy expense to bear.

160k km is technology at work and I stand updated (thanks, R2D2...), but members here have been discussing replacements at 10k km. That's worrisome/ridiculous.

Screwdrivers to reset spark plug gaps? It happens only in India... Plug gap setting tools cost peanuts. Is the recommendation against sand-blasting & gap resetting a universal trend internationally now?

Regular plugs cost approx, Rs.60 each - that's what MASS billed me for my Swift at the last change at 20k km. The expense is small, but why change if not required or if it doesn't make a difference to performance/FE?

[R2D2]

Originally Posted by SS-Traveller

160k km is technology at work and I stand updated (thanks, R2D2...), but members here have been discussing replacements at 10k km. That's worrisome/ridiculous.

Screwdrivers to reset spark plug gaps? It happens only in India... Plug gap setting tools cost peanuts. Is the recommendation against sand-blasting & gap resetting a universal trend internationally now?

Regular plugs cost approx, Rs.60 each - that's what MASS billed me for my Swift at the last change at 20k km. The expense is small, but why change if not required or if it doesn't make a difference to performance/FE?

A 10K km interval is too short and they are wasting money. Not required unless the mfr explicitly says so. Honestly I cant think of any modern car mfr that would insist on SP replacements every 10k!

The screwdriver is used to lift the negative electrode and increase the gap. Problems that arise out of this are:

a) Most people/mechanics tend to insert the screwdriver thru the side of the neg electrode and lift upwards. The gap increases but the neg electrode winds up being not parallel to the positive which introduces unevenness in the gap. Most importantly this can weaken the 'solder' joint of the neg elec to the spark plug body. You know what would happen if the neg electrode were to come loose during operation or God forbid come right off and fall into the cylinder. I have seen it happen on my friends bike in my college days. The piston and block were history and luckily for him his crankcase wasnt busted.

b) Inserting a screwdriver also damages the wear resist coating on the electrodes

No car mfr that I know of recommends gap setting anymore. Even aftermarket plugs come pre-gapped from the SP factory. Use the plug for xx thousand kms and throw it away. Service centres replace consumables like SPs at recommended service intervals.

Rgds,

[amit_mechengg]

10k kms is too short for spark plugs to be changed. i havent changed the plug on myTVS Victor since 3-4 years. still my bike cold starts in the morning in one kick. even when i inspect the plug its as brand as new.
mine is champion. mico doesnt go well with Victor.

[Raccoon]

While 10,000 km is way too soon for changing plugs in cars, its possible to require a plug change at this interval on bikes... eps. those that are ridden hard.

Amit mech... have you tried NGK? You will likely find it better. Its been happily sparking away in my Shogun since over half a decade. But yes, the bike hasn't been used a lot. Bought it from the TVS dealer.

[R2D2]

Originally Posted by Raccoon

While 10,000 km is way too soon for changing plugs in cars, its possible to require a plug change at this interval on bikes... eps. those that are ridden hard.

Amit mech... have you tried NGK? You will likely find it better. Its been happily sparking away in my Shogun since over half a decade. But yes, the bike hasn't been used a lot. Bought it from the TVS dealer.

Raccoon, you're absolutely right. Bikes need SP replacements far sooner than cars. A 2 stroke bike will need a new SP at 8-10K kms while a 4 stroker at about 15-20K kms. Cars can go way beyond that.

Rgds,

[amit_mechengg]

Originally Posted by Raccoon

While 10,000 km is way too soon for changing plugs in cars, its possible to require a plug change at this interval on bikes... eps. those that are ridden hard.

Amit mech... have you tried NGK? You will likely find it better. Its been happily sparking away in my Shogun since over half a decade. But yes, the bike hasn't been used a lot. Bought it from the TVS dealer.

i havent tried them on bike but they are doing awesome on my alto since 25k plus. victor has a peculiar problem. when u put mico plug onto it it misfires and champion plug does a good job here.
shogun is a master piece from suzuki.i have driven it extensively. also raced with it. love that bike. except the mileage haha

[dashoin]

Technology has a part to play here.

These days every manufacturer uses CDi (Capacitor Discharge - it allows delivery of higher voltages and power) technology to provide power for the spark plugs. The capacitor allows a steep front for the voltage giving a better voltage profile at the plug gap which leads to lesser erosion of the electrodes in properly set electrodes. With the introduction of MPFI engines, the timing and duration of the spark is also controlled - to ensure complete combustion. As the plugs are firing at the correct time, chances of fouling are minimum and hence cleaning intervals are reduced. There is nothing wrong in cleaning the spark plugs on a regular basis, just that you might end up changing the gap and cracking the porcellain body. BTW, there is no harm in carrying the old plugs as a back up. Drive a car with one cylinder not firing and feel the pain. As a routine, I get my plugs cleaned at the service and replace them at the recommended intervals - disacrded ones are used as spares and always in the boot - for emergencies. They are usually not worn out and also endup doing duty in the scooter.

Coming to the good old days, cleaning of plugs was a routine affair with the CB type (Contact breaker) ignition. The timing was done by the CB pint or the distributor - depending on the number of cylinders. Power was derived from a coil in the magneto / dynamo and voltage profile generally varied with each spark. Frequent regapping and irrgular volategs also wore out the plugs much faster. A capacitor was provided accross the CB points to reduce contact erosion. Just have a look at old cars / bikes / scooters with this kind of ignition and you would begin to appreciate how fast technology has progressed. Those with Bajaj scooters might remember the days when the scooter would overflow and you had to clean and dry the plug. That is where the 10 K limit came in although I remember replacing plugs at every 5 k. I still carry spare plugs in my scooter- you never know where you might need them.

Multi electrode plugs are not new -my dad has seen them in piston-type helicopter engines in his early flying days ( 60`s) - issue was more of reliability of spark firing in air. You wouldnt like to be in a helicopter with piston engines getting misfires over the mountains - would you .

I guess that deals with the history part of it.

[SS-Traveller]

Was browsing these spark pug manufacturers' websites and got some of the answers I was looking for:
A) Should a plug be cleaned or not, and why - read ChampionSparkplugs.com=.
B) Can upgrading spark plugs enhance stock engine performance? Read NGK Spark Plugs USA. To quote from the page, "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."