Platinum Spark Plugs

Time to change the spark plugs again! Was wondering about the pros and cons (if any) about using platimum vs normal plugs (apart from the price). Wonder if anyone can comment on them. Also would be interested to hear if anyone has had any improvement in performance using the Bosch +2 and +4 platinum plugs - are they really worth the extra money.

Yes you can see improvement with +4 in turbocharged, superchared and high compression engines.
+2 and regular platinums in regular engines the only improvement is longer service or replacement interval life.

no
I counter the fact that they not only are worse, they will have a shorter life span.

your plugs will stop being effecient when they are dirty. You cannot take out and clean a platinum plug you will ruin it and the metal is too brittle.

resistance in the plug is higher, platinum conducts worse than copper. its a material used for heat resistance.

only if your car came from the factory with platinum plugs should you use them. these cars have a combustion chamber made to realisticly give the plug a chance at life advertised.

I have a metro. Ive driven with them both back to back, recently.

use ngk or bosch regular copper plugs you will get better performance and gas mileage.

Thanks for the feedback - I guess I'll just stick to the regular plugs. Yes, good point about the conductivity - just checked the electrical conductance table and did not realize what a poor electrical conductor platinum is compared to copper. Of course copper is one of the best conductors of electricity.

A platinum plug will perform the same as a regular plug with a slightly larger gap. For example, a standard plug with a .031-.035 gap should be set to .039-.044 with a platinum plug. It will take more voltage for the spark to clear the gap, therefore, creating a spark of equalivent temperature. And the platinums will last a LOT longer, and maintain a sharp edge on the electrode much longer than a standard plug. Performance-wise, no, there is no advantage to a platinum plug. If you want a flat out performance boosting plug, get Iridium. But, they don't last very long until the electrode starts to break down. If you want a better spark, upgrade your coil and wires. A nice Blaster SS coil is only about $40, and you get a 48,000 volt spark. It takes about 20 minutes to install it into your car, and it's a big improvement. So if you're gonna piss money away, piss it away at the start of the spark, not the end. You'll get way better results.

In every automobile that I've bought (all used - won't piss money away on a new car),
I found a consistant 2-3 mpg increase by putting Bosch Platinum Plugs in them.

Those plugs have a porcelain inner plug with a tiny hole the spark goes into.

I have had parts clerks tell me some cars do better with them and others that they
actually do no good in. Personally, I think that is all rubbish.

All of mine did better.

VW Rabbit, Honda Civic, Chevy Suburban, two Jeep Cherokees, now my Geo 3 cylinder.

Be a scientist, my man - do the EXPERIMENT!

Only costs a few bucks more to try them.

Be sure to determine your current mpg first, so you'll know if there is an improvement!

If not satisfied, put the old types back!

That is how we find answers!

DoctorBill

PS - "Conductivity" variability is of little concern at 15,000 volts. And no spark plug is made
of solid Platinum! Platinum plated. Platinum currently goes for about $1,150 per ounce!
http://www.kitco.com/market/

:grinyes: Well I'm an engineer (I guess that's close enough to being a scientist) and am always doing experiments (developing new products) although generally always for other people. Yes, lots of different opinions and I guess the only way to find out is to try it. Not sure why there is such a difference of opinions on the subject - pretty much the same if you look on the web - some people claim better performance and others worse performance. And yes, I guess the amount of current being conducted at that voltage is pretty small anyway.

A platinum plug will perform the same as a regular plug with a slightly larger gap. For example, a standard plug with a .031-.035 gap should be set to .039-.044 with a platinum plug. It will take more voltage for the spark to clear the gap, therefore, creating a spark of equalivent temperature. And the platinums will last a LOT longer, and maintain a sharp edge on the electrode much longer than a standard plug. Performance-wise, no, there is no advantage to a platinum plug. If you want a flat out performance boosting plug, get Iridium. But, they don't last very long until the electrode starts to break down. If you want a better spark, upgrade your coil and wires. A nice Blaster SS coil is only about $40, and you get a 48,000 volt spark. It takes about 20 minutes to install it into your car, and it's a big improvement. So if you're gonna piss money away, piss it away at the start of the spark, not the end. You'll get way better results.

This performance improvement due to the coil - can you quantify that - do you mean better acceleration, power or economy or what exactly. Never heard of this product. Also is it a direct replacement for the existing coils.

look

your car cost at least 10k new.

ok. If platinum plugs gave you an increase in mpg, like 1 mpg. forget that, 1/50 mpg.

1 horsepower...... 1/10 of one horsepower

suzuki would have put them in the car to start with. they would have sprung for the um.... $1.50 more. They might even get a deal on them. Being an auto manufacturer and all. They might even have a good idea what sort of difference it would make in performance.

platinum is a heat resistant metal. It is used in such as mufflers. a platinum plug is a copper platinum alloy.

In theory they will "LAST' 100k miles.

ANYONE

ANYONE who thinks that their plugs go bad by the spark melting the gap....
doesnt know anything about cars. Im sorry. Hopefully I can help you learn.

Your plugs go bad when they are dirty. when carbon has built up on them resisting the spark.
platinum plugs will get dirty just as fast. only you cant clean them with a brush.
a softer copper plug, can be regapped and the dirt filed off and put right in.

So it has a LONGER possible life, although really its just the same because youre likely to just replace it.

I have tested it. with 3 different kinds of plugs, recently. The copper, being a better conducter of electricity has an advantage in performance right away, when new.

some newer cars, newer than your metro, use such powerful spark that the DISADVANTAGE, the resistance of platinum is almost nothing. The chamber the plug goes into has a special grate to keep blow back gasses from forming deposits on the spark plug. These cars keep their spark plugs cleaner longer. They come from the factory with platinum spark plugs installed. these cars would do well to have platinum spark plugs, such as a new corvette or integra or some such. these cars use capacitorys on each plug wire.
Does your metro do this? No.

your new platinum plugs were clean. Buy three new ngk plugs and you will notice a difference. right away like I just did when i took out the autolite platinums and put in ngk plugs. the new platinums were much worse than the bosch standards that were in there before and had about 30k miles on them.

I asked my imported car parts guy about Bosch platinum plugs and he told me that NKG would be a better choice for my 3 cyl 1.0 '96

I asked my imported car parts guy about Bosch platinum plugs and he told me that NKG would be a better choice for my 3 cyl 1.0 '96

yes ngk plugs are exactly what you should use. Seeing as not only are they more expensive, suzuki sprang for them in the final assembly of your car. If bosch were better or the same they would have used those

go ahead and buy a set of 3 of each and watch. I mean this is the perfect car to experiment by feel, the small difference of spark will show right from a dead stop.

Youll even see by mixing, put a bosch platinum in one cylinder and watch the vibration.

all testing and performance and driveability were done by the manf with ngk plugs in there. So even if iridium or titanium or dilithium positronic plugs were put in somehow magically creating more spark ( impossible) the fuel and timing is not tuned for it, it could only create predetonation at best.

The xfi uses a stronger coil and advanced timing. And ngk plugs. It reality Ive seen the xfi get worse gas mileage than the standard because it is a trick that probably only runs right when its new.

i need to add to the spark plug concept Im trying to relate ok, so I dont confuse anyone.

No spark plug makes more spark. none. what you are trying to do is perfect the TIMING of the spark. ok well iridium does ok by chemical reaction but nm.

When it gets dirty, the TIMING of the spark is changed. The plugs are no longer firing in perfect TIMING to eachother and the fuel bursts.

By changing spark plug brands, you are slighly changing the TIMING of the spark.

a platinum plug could not make the TIMING of the spark any better, it could only make it worse or at best do nothing.

in theory as some components of your vehicle age the gap of your spark plugs changing could help performance as opposed to what was stock. So in theory changing from the stock ngk plugs to something else could help a out of tune vehicle.
Im just trying to paint a possible scenario for people possibly giving themselves bad data. because its actually a bass ackwards way to do things. you can put the wrong plugs in and change the distributor timing even. reprogram the ecu for different fuel bursts....
.
but if any plug other than the stock plug makes your car run better, then your car is screwed up. It could happen dont get me wrong. But it tells you something else also.

When I first got my Metro it was not idling smoothly. I pulled the plugs and they happened to be the Platinum variety, Bosch.

I replaced them with NGK and everything smoothed right out.

And it is true that some vehicles just do not like those plugs. If I were to put them in my 93 Olds 3.4 DOHC engine it would run crappier, I've seen it before. They don't like the 'waste spark' ignition system used on that type of engine.

I figure that since the Japs that built the Metro put NGK's in it, they must know what they are doing since they designed it.

More interesting opinions. Anyway I have decided to stick with the NGKs this time. Interestingly the FSM from GM does specifically recommend either Denso or NGK plugs. Since they do not specifically recommend anything else as far as a brand is concerned maybe there is a reason for this as some are suggesting.

When I first got my Metro it was not idling smoothly. I pulled the plugs and they happened to be the Platinum variety, Bosch.

I replaced them with NGK and everything smoothed right out.

And it is true that some vehicles just do not like those plugs. If I were to put them in my 93 Olds 3.4 DOHC engine it would run crappier, I've seen it before. They don't like the 'waste spark' ignition system used on that type of engine.

I figure that since the Japs that built the Metro put NGK's in it, they must know what they are doing since they designed it.

As an alternative is it possible the plugs were damaged rather than this being due to them being platinums.

i need to add to the spark plug concept Im trying to relate ok, so I dont confuse anyone.

No spark plug makes more spark. none. what you are trying to do is perfect the TIMING of the spark. ok well iridium does ok by chemical reaction but nm.

When it gets dirty, the TIMING of the spark is changed. The plugs are no longer firing in perfect TIMING to eachother and the fuel bursts.

By changing spark plug brands, you are slighly changing the TIMING of the spark.

a platinum plug could not make the TIMING of the spark any better, it could only make it worse or at best do nothing.

in theory as some components of your vehicle age the gap of your spark plugs changing could help performance as opposed to what was stock. So in theory changing from the stock ngk plugs to something else could help a out of tune vehicle.
Im just trying to paint a possible scenario for people possibly giving themselves bad data. because its actually a bass ackwards way to do things. you can put the wrong plugs in and change the distributor timing even. reprogram the ecu for different fuel bursts....
.
but if any plug other than the stock plug makes your car run better, then your car is screwed up. It could happen dont get me wrong. But it tells you something else also.


Hmmm....don't follow the logic here. How does the plug getting dirty and changing the time at which the spark occurs (which I agree can happen) relate with using platinums. Any existing plug can get dirty and cause this - how do the platinums play a part in that. And yes I agree it is the voltage across the plug that determines the size and intensity of the spark - not the plug itself. I cannot see using a different metal can cause a timing change - until current actually flows the conductance is not relevant. The gap across the electrodes basically form a capacitor and the rate of rise of voltage across the gap is simply related to the dielectric constant of free space and the electrode area. This should happen until the air ionizes and then we get the spark.

Completely lost me on the sentence about irridium.

[QUOTE=stamar] these cars use capacitorys on each plug wire.
Does your metro do this? No.


Stamar
Tell me more about the capacitorys this sounds fascinating
Unbe

Hmmm....don't follow the logic here. How does the plug getting dirty and changing the time at which the spark occurs (which I agree can happen) relate with using platinums. Any existing plug can get dirty and cause this - how do the platinums play a part in that. And yes I agree it is the voltage across the plug that determines the size and intensity of the spark - not the plug itself. I cannot see using a different metal can cause a timing change - until current actually flows the conductance is not relevant. The gap across the electrodes basically form a capacitor and the rate of rise of voltage across the gap is simply related to the dielectric constant of free space and the electrode area. This should happen until the air ionizes and then we get the spark.

Completely lost me on the sentence about irridium.

Slightly revising my posting having thought about it a bit. Actually during the time when the voltage is rising on the coil some current will flow to charging the electrodes of the plug. Assuming a step type voltage from the coil, initally the current flow will be large and then will slow down and decay as the charge builds up. The shape of the charge will follow an exponential curve and will be determined by the time constant (RC) of the circuit. Since the resistance is involved, this indirectly suggests that the conductance is relevant. However, since this pertains to the wiring from the coils to the actual airgap the variation in resistance between a copper plug and a plat plug should be very small given the proprtion of the resistance due to the electrodes. So, yes there will be an effect but if you do the math it works out to be a very small number.

Slightly revising my posting having thought about it a bit. Actually during the time when the voltage is rising on the coil some current will flow to charging the electrodes of the plug. Assuming a step type voltage from the coil, initally the current flow will be large and then will slow down and decay as the charge builds up. The shape of the charge will follow an exponential curve and will be determined by the time constant (RC) of the circuit. Since the resistance is involved, this indirectly suggests that the conductance is relevant. However, since this pertains to the wiring from the coils to the actual airgap the variation in resistance between a copper plug and a plat plug should be very small given the proprtion of the resistance due to the electrodes. So, yes there will be an effect but if you do the math it works out to be a very small number.

If you are interested in how spark plugs work the internet is all yours.

i will start you on something but google is better
http://en.wikipedia.org/wiki/Spark_plug

you can even see dirt change the timing of plugs with your eyes
I mean, its enough to see. The gap is set at a certain height, the material is a certain electronic value. when it changes, the spark hits at a different time. enough to see. a split second mind you

If you are interested in writing out the physics/chemistry equations to spark plugs youre more into it than I am. What is happening is the timing of an explosion. The smallest difference is enough.

Different plugs of different makes and materials may list that they are the same. But they are not quite, not as consistant as one plug from one make.

plugs for the same car can even have a different value. this value is a change in the timing based on whether the car will be operating more from start up or more from normal operating temperatures.

electricity can hit at the same time, but its height and value of spark change dramatically in time at the other end of the plug, causing combustion at a different time based on the plug in the middle.
You could move your distributer as well. But the plug manufacturers give you another thing to consume by plugs of different timing.

[quote=stamar] these cars use capacitorys on each plug wire.
Does your metro do this? No.


Stamar
Tell me more about the capacitorys this sounds fascinating
Unbe
modern cars use wires with capacitors, spark plugs with capacitors or coils with capacitors

you can buy these kind of ignition systems seperately.
this is one chosen at random
http://froogle.google.com/froogle_cluster?q=capacitor+spark+plug+wires&pid=4838477716339091401&oid=12841202597399956237&btnG=Search+Froogle&scoring=mrd&hl=en

eventually I need to add, that no matter how much spark you have nothing changes if you dont have more fuel and air. That is all that can increase performance.

More spark actually decreases performance. It robs electricity that could be powering the car.

you can even see dirt change the timing of plugs with your eyes
I mean, its enough to see. The gap is set at a certain height, the material is a certain electronic value. when it changes, the spark hits at a different time. enough to see. a split second mind you



Well, yes that's correct. The more scientific way to think about this is with a capacitor model as I mentioned earlier. Dirt in the gap will change the dielectric medium of this "capacitor" and the time taken to chage it up will change (the charge curve shape will change) and the time taken for the voltage to reach breakdown will change and hence the timing of the spark. However, my point was that the use of platinum will also change this curve as it will change the time constant due to the different conductance but whether it will be noticeable is another matter. I can put down some acutal math to prove this. I have yet to find a web site that says that the use of plats in place of a regular plug will screw up perfomance. If anyone find such a site please post.

Here is a link which shows what the charging curve function would look like assuming a step input.

http://hyperphysics.phy-astr.gsu.edu/hbase/electric/capchg.html

[quote=unbe]
modern cars use wires with capacitors, spark plugs with capacitors or coils with capacitors

you can buy these kind of ignition systems seperately.
this is one chosen at random
http://froogle.google.com/froogle_cluster?q=capacitor+spark+plug+wires&pid=4838477716339091401&oid=12841202597399956237&btnG=Search+Froogle&scoring=mrd&hl=en

eventually I need to add, that no matter how much spark you have nothing changes if you dont have more fuel and air. That is all that can increase performance.

More spark actually decreases performance. It robs electricity that could be powering the car.


I suspect these systems are using a cap in shunt with the plug so while the voltage is rising the coil is charging the cap as well a building the voltage across the electrodes. When the air ionizes, the coil as well as the cap discharge through the electrodes thus boosting the current and giving a bigger spark. As I see it you would also need a more powerful coil to make this work - adding a cap without a better coil may actually mess things up. Also as mentioned if the exsiting spark is already adequete this system may not achive much in terms of improving things.