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Hello All .
If I read the owners manual correctly on my 1986 Spider, I have ti change the spark plugs every 12,000-13,000 miles. Seems extreme but a simple job to do. Is this correct????

Also, which are the best spark plugs to buy? I ordered Champion Iridium 9804's. Any good?
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If your engine and carbies are in excellent condition and your distributor is excellent and timing is spot on for the fuel you have, then using original OEM Golden Lodge spark plugs 2HL may suit (Medium temp plug). It also depends on your driving style, plus the octane rating of your fuel. Driving the car in the city in 5th gear to save engine revs and fuel at 30mph or 50km/hr is really false economy and quickly carbons up the plugs and you end up running on 2-3 cylinders.
These 105 engines were built to be run for long distances like from Rome to Milan on Italy's Autostrata of speeds up to 80 mph (130km/hr).

It always amazes me how people think the spark plugs are the issue, when it is also down to driving style and how worn out the engine, and if it has poorly tuned carbies and distributor worn out or set incorrectly. If you have oil leaking into the combustion chamber from worn out piston rings, valve guides and seals of course you are going to get carboned up spark plugs. The Golden Lodge spark plugs don't like having to burn oil as well as fuel. Some of the Iridium plugs don't mind burning the oil. Of course you don't want to be burning oil too long in the combustion chamber as pretty soon your pistons and rings and liner walls and valves will suffer with gummed up carbon deposits that can cause more damage, where you end up needing new liners.
Your engine, your investment, your choice.
Regards Steve
 

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If you have a copy of Overhead Cams Volume 41 number 11 November 2001. Read Wes Ingram's 'A few engine building tips'
on page 8 and 9 he mentions The soft Borgo oil rings are one piece cast iron. They seat fast and wear out fast as fast.' and 'Good compression readings are not a positive indicator of good oil rings. Alfas are notorious oil burners'. Piston 'Ring life is shortened from the effects of oil dilution' in particular 'with cars using SPICA pumps'.

So as I mentioned before, if you are burning oil your Golden lodge 2HL spark plugs are not going to like it, as they will carbon up. You are better off with spark plugs that can handle burning oil in the combustion chamber, but as these will end up coated in burnt oil, you may have to change these sooner than you think.
Steve
 

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You opened a can of worms here. Everyone has different opinions on plugs just like on tires and car colors.
I have had good luck with Champions, NGKs and Golden Lodge
 

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I love opinions and in a forum you should be able to voice your opinion.
I also like facts and here are the facts, technical details from Wes Ingram has discussed in an open forum, which can assist members form their own opinion.
Steve
 

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Hello All .
If I read the owners manual correctly on my 1986 Spider, I have ti change the spark plugs every 12,000-13,000 miles. Seems extreme but a simple job to do. Is this correct????

Also, which are the best spark plugs to buy? I ordered Champion Iridium 9804's. Any good? View attachment 1719335
I have the NGK's also like the others but I would not hesitate to use to Champion Iridium spark plugs.
 

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Spiders: 1971 red, 1971 white, 1973 yellow, 1974 Silver, 1980 Brown, 1982 Blue, 1992 and 93 Green
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With these motors having hemispherical combustion chambers, the Lodge plugs seem like the best plugs. I would think that the four electrodes would be helpful, because there's no electrode to block the flow of combustion - the single electrode is not symmetrical, so it will block some of the combustion. I believe Bosch makes a four electrode plug too - and I believe it's platinum, so it may work even better than the Lodge plugs???

The other point to consider is that theoretical analysis is just that. Real life data and back of seat sensation is what truly matters.

I haven't changed the spark plugs on any of my Alfa cars yet, so I can't give real life data. And I don't even know which plugs are in my cars! I figure that I will need to changed them - maybe sooner than later. I'm very interested to hear more about what everyone here uses and why they choose them over another brand.
 

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I used the Bosch Plus 4 in one or more of my Alfas for a while but found that they fouled rather quickly. My thought at the time was that Bosch got the heat range wrong for the cars, and the plugs they recommended were too cold. Stopped using them, never went back to them.

The only real problem I have with the Lodge is that they are very expensive in comparison, for some reason. I don't think they really work any better than other plugs, four electrodes or not, in an engine in good condition. Some who are into original authenticity appearances use them, some Alfas coming from the factory with them I reckon.

In my decades of owning Alfas using plugs of various makes, including Lodge, I ended up with the relatively inexpensive but long lasting nonfouling newer tech NGK Iridiums. If nothing else, they work just fine in the Alfa V6 engine, staying very clean and always firing, as far as I can tell. Can go thousands of miles without checking them for deposits, etc.

Some do prefer Champions of one sort, another quality plug.

So, your choice. Really, some make too much of a deal about plugs and which ones are best for their cars, IMO. You will find that most plugs will work well enough, the determining factors being cost and whether or not they have a tendency to foul too soon. Unless they continually want to foul quickly, I suspect you will not realistically detect any difference in engine performance, but that's just my own opinion.

In general, plugs are just plain better designed than they used to be.
 

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In general, plugs are just plain better designed than they used to be.
I agree, but why is that? Are they made from better materials than they were in the past? It's hard to believe that spark plug manufacturers would expend a lot of effort designing a plug that performs in an oily environment, since 99% of the cars on the road today don't burn much oil.
 

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My take: antipollution regulations/requirements here and abroad have required longer lasting cleaner running, more precise ignition plugs to match the much more precise systems in today's newer engines. Thus the introduction of newer designs using better materials, such as first the Platinum and then the Iridium electrodes, and even follow on from those materials.

It turns out they come across as working very well in older engines, being able to better handle the degraded engine internal environments of old.
 

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Agree with Del. The more fancy/precious metals introduced over time resisted deterioration of the plugs longer in the hostile environment in which they operate. 100,000km recommended change intervals are now commonplace. Plug type (shape) is another story.
 

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I agree, but why is that? Are they made from better materials than they were in the past? It's hard to believe that spark plug manufacturers would expend a lot of effort designing a plug that performs in an oily environment, since 99% of the cars on the road today don't burn much oil.
It's the materials. The old plugs didn't have platinum, iridium, ruthenium or palladium. They had a copper center electrode, which worked great when new, but the edges would round off, which changed the gap distance. The new high mileage plugs use a metal that deteriorates very slowly when it sparks, so the gap stays constant and performance isn't degraded.

Contrary to belief, copper is an incredibly good conductor. There's one valance electron, so it's easy to "pull" the electron from the atom - conducts electricity or the movement of electrons. New plugs also have a small dot of platinum on the ground electrode. So the ground electrode (bent part) doesn't wear out fast. Even though platinum, iridium, ruthenium and palladium are larger atoms (the valance electron is further from the nucleus, so it's easier to pull off), none of them has only one valance electron. They are good conductors, but not as good as copper. Silver is an even better conductor, but I've never heard of a silver electrode spark plug - maybe it's due to how easily silver oxidizes. And gold is also an excellent conductor as well. Many electrical switches and connectors are gold plated - think about all the gold in the phone company equipment!

Back to spark plugs. When the Federal gov't made auto manufacturers decrease emissions, the auto makers needed a long life spark plug. That's when we started seeing single platinum spark plugs. For quite a few years, Toyota has recommended a spark plug change at 12 years or 120K miles. A normal copper electrode plug won't cut it. Also, since copper is an excellent conductor, you most likely won't see a difference in performance when switching to platinum, palladium, etc plugs. They just wear much, much slower.
 

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My take: antipollution regulations/requirements here and abroad have required longer lasting cleaner running, more precise ignition plugs to match the much more precise systems in today's newer engines. Thus the introduction of newer designs using better materials, such as first the Platinum and then the Iridium electrodes, and even follow on from those materials.

It turns out they come across as working very well in older engines, being able to better handle the degraded engine internal environments of old.
You beat me to it!
 

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Autobroker said: ‘When the Federal gov't made auto manufacturers decrease emissions, the auto makers needed a long life spark plug. That's when we started seeing single platinum spark plugs.’

A bit chicken-and-egg, is my take. What came first, plug manufacturers looking for a marketing advantage, or car manufacturers (maybe coz of Fed Regs) demanding it? My dollar is on the former - car manufacturers do their emissions tests on new plugs, not 60,000km old ones no? There’s a post on another thread about a ‘new, even better’ precious metal plug…can’t remember the beaut, new, metal name….but I bet a second dollar it’s a marketing thing.
 

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The manufacturers are under a great deal of pressure from the Feds in this country and the governments abroad. In order to reach the high mileage long term pollution requirements, not just the new car requirements, they required plugs which would go the distance without changing, that's evidently part of the requirements. And as you know, in some cars, changing plugs can be somewhat of a pain.

Yes, I'm sure there are marketing considerations, but still, the plug designs are pretty much driven by the regulation requirements, IMO.
 
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