Is there a consensus on spark plug brand? I have always had luck w NGK, Champion appears to be oem. But maybe in the last 20 years there has been improvement?

I am not having a problem, but figured it has been a while, probably before I owned it.

thanks

 

NGK, Denso, heck even Autolite have all worked well in a LR V8, on the newer 05 and up LR V8's NGK are the OEM plug used.

 

The most important consideration for spark plugs is that they are double-platinum, or double some other precious metal (often iridium).

The reason is that the DII uses a wasted spark ignition system. Google it. Conventional copper plugs wear out quickly if used in a wasted spark system.

Before I started taking care of my truck myself, a local shop installed conventional copper plugs. They lasted just 13,000 miles before the misfires appeared. I replaced them with the OEM Champion 7070s (RC11 PYP B4). They are double-platinum, and were still going strong 72,000 miles later when I replaced them proactively only because I was replacing the wires.

There is a lot of snake oil marketing with spark plugs. On top of that there are heat range specifications to be considered. Other brands that are double-platinum and in the correct heat range may work equally well in your DII, but the 7070s are specified and proven.

 

Thanks, that is very interesting, glad I asked.

per AB, the oem champion is NLP100320, 7546, double platinum. Any reason to use 7070 instead?

is double iridium the same as double spark? Seems like it should be, but wanted to check.

 

It's interesting that when I search online for Champion 7546 the search returns RC11PYBB4, the number for the 7070s. (I don't know why Champion uses two different numbering schemes. I do know that every character in the longer number has a meaning. There is a translation table online somewhere.)

They may be equivalents. All I know is this is what is documented in the RAVE.

Oddly, the RN11 YCC is a "Copper Plus" plug. I don't know what Copper Plus means, and I don't know why Land Rover changed the spec for the '03s-'04s with the 4.6 engine.

What I do know is that I would use 7070s in any DII.

"If it ain't broke, don't fix it."

 

Autolite Iridium. Gap them to .035 - XP3924 4000 Ohm resistance. These are by far the best plugs you can buy. I use them in everything. Porsche, McLaren, LS turbo motors, whatever I put plugs in gets Autolite Iridium.

 

Got, will re-gap. Im sure you dont recall, but you pinned the cylinders on this motor a few years ago. Still running beautifully, quiet, pulls well, no temp issues.

 

For brand it really just comes down to personal preference. You're best to stick one brand you like and use it in everything because different brand plugs don't always read the same. I personally like NGKs, but I've also used AutoLite, Denso, Champion, ACDelco, etc. with perfect functionality.

At the end of the day, it really doesn't matter. As stated, if you want them to last a long time get double platinum or iridium's. Otherwise just pick what you like and stick to it.

 

Ive put 50k trouble free on these

 

I'veused E3 plugs for years which is what Disco Mike used to recommend.