I have a 1972 Morris Mini with the original 998cc engine. Can I use iridium spark plugs with this engine? It has the conventional coil, points and conderser. Thanks
Yes. Your auto parts dealer can look up the various spark plugs that are suitable for this engine.
There might be an issue. Most, if not all, iridium plugs come pre gapped at somewhere around .040". Your gap spec is probably around .030". Re-gapping these plugs without damaging them requires a lot of care. You even have to be careful when measuring the gap.
The high cost of irridium plugs is only worthwhile in an engine that has a computerized fuel metering system. An old carbureted engine will foul irridum plugs as quickly as the standard plugs that cost 1/8 the price. There is no benefit to using them in that engine.
It generally best to stick with the plug type the factory put in.
True with new or old cars.
With the old-fashioned ignition system, you will not see any performance improvements. The most you can hope for is not having to change the plugs for 100,000 miles. And, some plugs are just not happy with certain engines. It sounds like an semi-expensive experiment that will not make any gains I think you’re looking for.
Rod, that is not true. If he is using leaded gas, then there would be a fouling problem. As long as he keeps the carburetor adjusted properly, it wont foul the plugs.
I am not going to argue the economics of using the iridium plugs, but they do give a hotter spark so they will give the carburetor a little more latitude. But on the other side, there are usually fewer heat ranges available in these plugs. If the iridium plug just happens to be in the same heat range, he will get the most latitude. In fuel injected engines, the hotter spark gives the plug more latitude in heat ranges, that is why there are fewer of them. He will just have to take into consideration that the further away from the ideal heat range he is, the less latitude he will have with the carburetor.
Why use Iridium? It’s not going to make one molecule of difference in power or fuel economy but will deplete the bank account a bit more.
With the old-fashioned ignition system, you will not see any performance improvements.
You won’t see any performance improvements with a NEW ignition system either.
I seriously doubt you can even get iridium plugs for this vehicle. And NOT worth it…
Just get the OEM type plug. Might be Bosch.
From 1962 'till 1974 the BLMCs sold in the US had 1100 and 1300 engines with Champion N9Y plugs.
Thank you all for your feedback. I do not drive the car on the highway very often, mostly because of safety concerns with the crazy Massachusetts drivers. The car has no safety equipment other than seatbelts. I have noticed that after a good highway run the car runs better and am thinking that iridium plugs may stay cleaner longer. I did inquire with NKG and was told that they likely have a compatable plug and that they require much less enery to fire and that they fire hotter. At about $5 a piece I may try them out to see if there is a difference. Again, thanks all!
I have noticed that after a good highway run the car runs better and am thinking that iridium plugs may stay cleaner longer.
NOPE…There are not anti-fouling plugs. Iridium plugs do last longer…but not so sure on a NON-Electronic ignition system.
I did inquire with NKG and was told that they likely have a compatable plug and that they require much less enery to fire and that they fire hotter
That’s a load of cr*p. I LOVE NGK plugs…but who ever told you that sounds like NGK salesman. If Rod Knox is correct (which I think he probably is)…then stick with the Champion N9y plugs.
“That’s a load of cr*p.”
What part of that is a load of *? Iridium plugs do require less energy to fire, not because of the Iridium, but because the tip comes to a fine point, which generated a more concentrated corona, and it generates it quicker. That is why old racers used to file the tips of their spark plugs to a point. They didn’t need as much energy to fire, which gave them a higher RPM range as energy falls off with RPM in a points ignition system. They just didn’t last very long due to erosion. The iridium solves that.
For normal daily operation in a well maintained system, there is no benefit to Iridium except for life span. But at the edge of the operating envelope, they do have other benefits.
Rod Knox is correct, Champion N9Y it is - except it doesn’t exist anymore, but there is a replacement. In Bosch it was 175T30, same situation. I have driven those A-series engines for more than 30 years and they work perfectly with standard plugs. No need to do more. Now, if you were talking about a PerTronics ignition system, that would be an improvement. Maybe other brands too.
RN9YC has replaced the N9Y. It would have a resister to reduce radio interference and a copper core for who knows what reason. And for $2 each it will likely last as long as the iridiums. Fouling will most certainly be the cause for failure of whatever plug is in the engine and rare metals foul as quickly as iron. But there is some question as to what vehicle this is and which engine it is.
WHY ON EARTH IS THIS EVEN A DISCUSSION? Just put a nice set of cheap reliable Bosch Platinum’s or a set of NGK’s in there and be done with it… My 200+ Mph Motorcycle calls for Iridium plugs…WHY are you even pondering wasting the money on this silly venture…it will do nothing for you or the car
Blackbird