[sorry the title should say "NGK", not "NKG"!] Hi everyone, I did a search and found some people saying that you must not gap the DR8EIX Iridium plugs. The TR manual recommends a gap of 0.6 to 0.7mm gap, but I'm assuming it's for old school plugs. The DR8EIX is gapped at 0.8mm at the factory, but it's also a more modern plug. What do you guys do? Do you gap them before installing them? Thank you!
cristophe before you plug them in meassure the gap sometimes during transportation and handling the gap is not correct anymore since I do my job ( over 35 years ) I always test the gap but only a very few are out of limit. but even only one is not ok you may get problems
The spark's ability to jump an air gap is based on the system's voltage. The 'modern' plug may have a larger gap to take advantage of more modern higher voltage systems. Without an upgrade to the TR ignition system, I'd suggest that the OEM gap is your best choice. Life Is Good, vincenzo
Same here, but if you do an adjustment you need to be really careful because these exotic metals like Iridium are brittle at room temperature, as is the bond between the tiny chunks and the substrate, and the diameter is small (IIRC, they specifically had a "do not adjust" symbol on the box, but don't know if that's still shown). I check the gap like romano mentioned (but have never found an IX to be out), but by using a wire gauge at the low end of the spec, or a little less, and then pass the wire gauge thru the gap without touching and judge the remaining slop (rather than dragging a flat gauge tightly thru the gap).
I gap every single plug. I installed a set of NGK PMR8B Friday whose gaps out of the box ranged from less than my .5mm plug gapping gauge would measure to over .8mm. While a large plug gap may still fire the larger gap speeds flame propagation and can lead to detonation. Not gapping plugs is never a good idea.
You guys aren't really addressing what the OP asked. The question isn't "should you measure the gap on all new spark plugs in a set and correct any that need it to make them all the same if they aren't?" (to which the answer is obviously "yes"), but rather, "the TR spec for the original spark plugs (which are a different technology) is 0.6-0.7mm, but NGK recommends a plug that comes preset to 0.8 mm, do I need to change it?". I haven't noted any trouble using the 0.8mm distance (and references indicate that the shape of the electrodes does have an effect on the voltage required not just the air gap distance).
His first sentence suggested to me has been told not to gap iridium plugs. Further he said all were gapped at .8. My statement was to say neither was true. I do gap them to .6 BTW. Ferrari even on later models with NGK iridium as OE call for .6mm The NGK catalog I have says nothing about installing them as gapped, it says right in the catalog to gap them at .025. .8mm is closer to .031.
A rounded shape (worn electrode) does in fact require higher voltage to fire. It is the primary cause behind old, failed plugs. A new (sharp edge) electrode will have little change in required voltage to fire based on the electrode shape. The air gap is by far the biggest change in resistance. Stuff like the enclosed pic is mostly BS... but since they have more 'sharp edges' they may last longer. Note too, that the heavy shrouding of the ground electrodes likely hinders the flame front propagation. Do folks still index their plugs these days? Sorry to digress.. YMMV, vincenzo Image Unavailable, Please Login
That is why the PMR8"B" exists. The iridium plugs only had an iridium center electrode and when the ground electrode eroded it caused misfiring the computers could detect and set a CEL. Ferrari had NGK use iridium for both electrodes to get the plugs to last between scheduled changes. The "B" denotes the change. Bosch has marketed a plug like the one shown called an "anti oil fouling " plug. Theory was it would find some place to jump a spark too. Worked but not well.
Is something with an iridium ground available for the TR? Sound like a worthwhile add. Rgds, vincenzo
"Im on the pill", 'Yes maam I won this belt buckle in a Rodeo", "The check is in the mail", "I promise I wont com....", "No need to gap plugs". All lies. Check every plug you get, every time.
I didn't know my question would "spark" such a debate! (you can come see me at the comedy club every Tuesday at 8pm) I think I'm just as confused as a few days ago, I measured the gap on all of them and they were all perfectly consistent at 0.8. In doubt, I installed them as is to see how the car would run, and it ran great. I did the Shamile install, torqued at 15lb, slacked, then to 12lb. It's easy enough to regap them to 0.6 if the consensus goes this way, but so far the opinions seem to split in two camps: verify the gap but leave them as is, and gap them to 0.6.
NGK and Ferrari say to gap them. They are the only real authorities on the matter, not sure how that constitutes debate. I drive cars every week that I am told run perfectly that do not.
Now there is a debatable topic. I have never seen an auto manufacturer, any auto manufacturer use anti seize.
that is the reason that I often get cylinder heads ( not only F ) to remove the broken plugs or the rest of the parts of the plugs so for daily used cars with 30 or 40k km each year I prefer anti size. abd for all cars with aluminum heads also
http://www.b2600i.com/images/ngk_tb_0630111_antisieze.pdf Again, I tend to take advice from the recognized authorities on the matter. Voodoo never worked well for me.
Looks like plugs have gotten better over the last 50yrs. That changed my mind..... 50yrs of habit are rarely questioned! Change is hard! Life Is Good, vincenzo Image Unavailable, Please Login
The information is all out there. The funny thing is companies who make this stuff are pretty helpful when it comes to using it correctly but they are the last asked and the first ignored. This thread is an outstanding example. Despite excellent information to the contrary in the form of instructions from both Ferrari and NGK the OP has chosen to ignore the information from both. Ignorance is a choice.
All right, easy Brian. Before pushing "ignorance" words around on me, I was in the middle of the work and asked the question. I got answers saying they should go in as is, among them from Steve who I trust tremendously, so I put them in as is. Then later the thread went on and others pushed for gaping them. I fail to see what you bring to the conversation by adopting this tone in your response.
FYI... 1.6 daNM = 16 NM = 11.8 FtLbf This is a very low value for clean dry threads. Use a 1/4" torque wrench for sure. I think that a torque re-check after a few heat cycles would be a good idea.... Image Unavailable, Please Login
