Never seize is a no-no. On the newer, everyday driver stuff w/ DIS, it is known to cause the unexplained, elusive misfire. Without getting into a big, long and boring lecture, on 1996 and newer vehicles (OBDII), use ONLY the plug that came OEM in it, even if the plugs cost $10 a whack. Take those Bosch plugs and throw them as far as you can get them into the weeds! They don't even belong in a weed eater! Being an ASE Master Tech for 20 years, I have a lot of hands-on experience with plugs and aluminum heads. Back in the 80's when aluminum heads were starting to be massed produced, the buzz was to pull the plugs on a cold engine. IMO, this turned out to be hogwash. If a plug was seized, a hot or cold engine didn't make a difference, and a hot engine doesn't cause a plug to gall, again IMO. I wouldn't think twice about putting a non-coated plug in a TA, BD or EB aluminum head. You won't be driving your car through a rust-belt winter, and if you're like me, you change them once a year anyway.
Larry did you end up using the smaller NGK FR-5? What is the 13/16" equivalent a 6BES? What torque are you using?
I have used the FR-5 since I got the new heads. It's a great plug, and on my engine, they come out a nice light brown/tan. I've been changing them yearly. The FR-5 is a V-power plug. There is very noticeable erosion of the "V" in the center electrode. Robby originally put a set of AC R43XLS plugs in it with a little anti-seize. I pulled them out immediately and replaced them with the NGK's. BTW, Alan runs the same plugs. They came in his motor straight from TSP.
I'm going by feel. I just don't trust a torque wrench in this situation to tell you the truth. I put them in by hand until they are finger tight. Then maybe a 1/2 turn more. When I take them out, the gasket looks like it is crushed, and I haven't seen any indication the plugs are leaking. The NGK BP5ES should be close in heat range, but the FR-5's are a projected nose design (even more than the BP-ES). Theory is they position the gap further into the combustion chamber, and they have a wider heat range supposedly running hotter at low RPM's and cooler at higher RPM's (cooled by intake charge). They make a noticeable difference in my engine. I ran the UR-5's in my iron heads. The FR-5 is the same plug with a flat seat and gasket.
oops, I guess I made a mistake. I used the Champion RC12YC recommended by Greg Gessler. I did use anti-seize. I don't see a coating on the plug but that doesn't mean it's not there. I can't remember ever seeing a plug that came with a coating. Does anyone know how to tell if a plug is coated?
Andy, If I remember correctly, JW was referring to the fact that NGK plugs have plated threads. The AC plugs do not. Champions do, I believe. http://www.ngksparkplugs.com/products/spark_plugs/vpower.asp?mode=nml
You're right Larry, I just checked on the Champion site..."Champions traditional plugs are all constructed with a corrosion resistant zinc plated shell." I have another set waiting to go in anyway. I install those dry.
I know your not supposed to put anti seize on the spark plug threads but i chickened out and did anyway. just a very light coating.
