What spark plugs do you use?

I use iridium plugs for everything.

 

I use NGK BPR9EIX Iridium in my 246gt.

 

https://www.ferrarichat.com/forum/threads/current-spark-plug-recommendations.578413/

 

Everybody has spark plug opinions, these are mine:

After over 35 years of testing engines on the dyno, my two main takeaways are:
1. Almost everybody runs too cold a spark plug.
2. Engines do not need near as much fuel as you think.

If you are using your Dino 206 and 246 like most collector cars are used today, I would start with NGK BPR6ES (unfortunately, the non-resistor BP6ES are no longer available). If you will run the car at 5,500-6,000 rpm for long distances, I would try BPR7ES plugs. If the cars ignition system and carburetion are in good shape and correctly tuned, there is no need for the more exotic/expensive design plugs. The standard style plugs will be fine. Spark plugs, in a correctly tuned engine, generally give a warning, when they are no longer functioning well, by the engine being harder to start from cold. When you began to experience this condition, it is time for new plugs.

 

+1 -- but can't agree about the "no need for the exotic/expensive design plugs". Iridium spark plugs have a so much better anti-fouling characteristic that they can provide amazing help/better longevity in carb applications IME (I agree that the price that many Shops charge for these is downright crazy and insulting, but www.clubplug.net is reasonable). I'd add that the 246 (and early carb 308) spark plug gap specification of 0.4-0.5 mm seems crazy small to me, and the "remove and inspect every 5000 km" and "replace every 10,000 km" specifications are why Iridium Spark Plugs got invented -- JMOs.

 

I have no problem with what Steve is saying. However, we have to understand WHY the platinum, iridium, precious metal electrode spark plug was developed. It was a result of the mandated federal emissions testing. These tests were so strict that ONE cylinder misfire during the test would cause the entire engine to fail the test. All this costs manufacturer's lots of money, so they put enormous pressure on the spark plug companies to develop spark plugs that were more resistant to a misfire condition. Also, there was a desire on the part of the manufacturer's to lengthen the "life" of the plugs in everyday usage, so they could advertise 50-100,000 mile plug changes. Cost was easily passed on to the new car purchaser. At the same time, ignition systems were rapidly advancing to produce greater kilovolt outputs and this also helped both the government test results and lengthened the life of ALL spark plugs.
As an aside, we use "standard" NGK plugs in all our vintage racing engines. We have no problems, but do replace them for every event. We tried the "precious" metal plugs but found no dyno power gains, nor additional benefits. Personally, I cannot recall having a standard plug foul on a correctly tuned Ferrari. However, this may be due more to careful selection of the heat range and making sure it was not too "cold" a plug.

 

+1 -- and it is kind of ironic that modern, fuel-injected, Lambda-closed-loop engines with great electronic ignition systems that have these exotic plugs probably need them the least (except for the extended mileage change interval that you noted). I would argue that the race weekend use case you mentioned (fresh plugs, few cold starts, and extended intervals of hard running) is very different from the use case of many cold starts and many short street-driving trips at sedate speeds over many years. If a Shop wanted to charge $25 each = yes, that would piss me off, but the $8.50 cost of an EIX plug vs the $4.50 cost of an ES plug would be worth it for a carb F in the non-race use case that I described IMO -- but we're all allowed to have different opinions .

 

NGK BPR7 / 8 ES (£3 each) are perfectly OK for the dino, the iridium plugs (£12) are not worth the money and dont cure a badly set up engine. Dont blame the plugs, its normally either fuel / poor carb setup (especially idle) or ignition related problems that cause the plug/s to misfire. Sort those out and the standard plug will go on for 15,000 miles min.

 

I use BPR6ES with lots of Autobahn use. Never had a problem. I needed to regap the breakerpoint 3 times now and still use the same plugs (but have a different ignition system than original).

 

I run the Stratos road car on the original Champion N60Y plugs with original Dinoplex and it seems to run fine. Plus I have about 400 NOS plugs so won't run out anytime soon.

 

I've been installing/using NGK BP6ES plugs in Daytonas for last couple of decades and due to aforementioned (by Dyke) ease/lack of availability of them, more recently BPR6ES, but both without any noticeable issues.

I recently came upon (disturbing) evidence of a relatively highly regarded shop having invoiced someone for (high priced ?) "Iridium" plugs, but the actual plugs in the engine are/were found to be just "standard" Nickel tip electrode models ...
.. and the shop wasn't that of the FChat méchant du jour, D.C.
OTOH, this is far from first time I've encountered (& documented) invoice/work order/-description or expected workmanship quality discrepancies from "highly regarded"(?) shops. Some have been quite surprising and even at levels of Cavallino or P.B.

 

As I drive my Dinos between 3000 and 4000 km each per year, I followed the recommendation of John Corbani and use NGK BPR8EIX Iridium in both Dino engines:
- 2,0 with fully original old Dinoplex
- 2,4 with Adrian's Bosch & Lumenition system.

Perfect (high spark energy) ignition in both cases, lubrication maintenance of distributor recommended every 15.000 km / 10.000 miles.

Works similarly well in my Alfa and my Jaguar.

 

Please take care of Chinese copy