My dealership is trying to sell me 2 NGK plugs for 50 dollars each but the same plug number at Canadian Tire is 19.99 each. Anyone know if there is a difference? Same brand, same number so I can't see how but figured I'd check here first.
I've been away from CNC machining for over 30yrs, at that time the precision and multi axis abilities were outstanding. I do not see it being that difficult to orientate the spindle and the flute engagement of the tap so that the start of the thread is exactly where you want it on a circumference. Based on the thread pitch and number of threads you can specify to the spark plug manufacturer index position based on a specific torque.really though, we all should think about it, if these were all specced for etec engines and infact, indexed based on BRPs spec, wouldn't that mean that all plugs would line up in the same place on all engines? would also mean that Rotaxs manufacturing and threading heads is on point perfect with every engine head they make, which i highly highly doubt is the case.
Or you can skip this & have the ground electrode 'shrouding' the spark.Just to reconfirm the indexed spark plug thing... I know for a fact that BRP plugs are indexed properly. This means that the threads in the heads are always clocked correctly - which as Candubrain said above, was trivial more than 3 decades ago - and the threads on the spark plug are also clocked correctly, if bought from BRP.
What I don't know, is if all plugs will index properly. My guess is that the plugs are not CNCd, meaning the threads would end up all over the place. BRP likely pays NGK a premium to sort the plugs and send a portion of the ones that are properly indexed to them. Why do they do this?
Because on an ETEC, the plug must be indexed. And training your dealers and every mechanic in that dealer on this is a headache from a logistics standpoint that they can simply avoid, by passing the cost on to the consumer. It's zero cost for them and saves massive troubleshooting and tech support issues. So if you buy the plug from your dealer and torque it to spec, it is guaranteed by BRP to work.
Now, NGK might clock all of their plugs. They might CNC them. I have no idea, and as I mentioned to me it's just not worth it since the savings are almost non existent, and I don't mind supporting my dealer (which was the best reply on here, by the way...it's a dark day when my dealer doesn't exist and ONLY the guy at the cantire parts counter can get me plugs. Half the guys and gals working there literally don't know how to find plugs unless you give them year, make, and model, and "Skidoo" isn't in their system...ask me how I know).
Anyways, all I'm trying to say is that if you buy them from BRP, they are guaranteed to work. The shop manual literally has two different procedures for if the plugs are BRP or not - if they are BRP, you torque to spec because they are already indexed. If not, you have to index them yourselves. Again, they might work otherwise. Indexing is also pretty damn easy to do, and Leo is right that an extra 15-30 degrees of rotation probably won't hurt anything. But the ~$40 every three years is - to me - a worthwhile price to pay to support my dealer, and not worry about any of this at all.
That's odd, not once did I ever foul a plug on any of my SDIs, including my '04.From the 2020 PAC:
View attachment 2011644
I know prior to 2018 when I was still running an SDI I thought the ECS plugs were pricy. 2004 was a costly year when the SDI was intro'd, as they'd foul a plug just looking @ the sled the wrong way...
Also I imagine the heads are CNC machined including the plug holes, so their accuracy might surprise you.