Your engine should have had single platinum plugs in it from the factory. The main difference is how long they will live compaired to copper. You will see mileage and performance gains with iridium plugs.

Case in point my LS1 when it came to me had single plats in it. I didnt know how long they had been in the engine or what type they were so I bought a new set. I picked up a set of ACD Iridium plugs and installed them. The plugs in the car looked fairly new but they were the wrong type. After this the engine had a noticable amount of more power and we got a couple extra MPG out of the job as well. Now the LS1 is made to run with Iridiums so putting lower grade is only going to hurt. My 3.8L came with double plat and when I put the new engine in I put in Iridiums. Not sure if it made a difference or not but the new engine did have better performance and better MPG... Could simply be that the new engine had 1/2 the miles the car had.

As for the Platinum +4 plugs... They are junk. I used to sell alot of them when they first hit the market, Sold alot of split fire plugs too for the same reason, they were new. Most people that put them in domestic 6 or 8 cylinder engines didnt like them and returned them a short while later. I did find that high revving 4 cylinder engines seem to like the +4 design. I would not buy them and I rarely even offer them to my customers when they ask for plugs.

Massey

 

Ok, so apparently it was just coincidence that I found that problem and the engine was fine at the time.
Problem is back. I started it up today and the oil pressure was jumping with the throttle again and it had the tapping. I took a video for you all. Although the tapping went away almost as soon as I got under the hood and the oil pressure went back to normal too.

http://www.youtube.com/watch?v=X0wDI...ature=youtu.be

 

look for spark jumping. recheck all the plug wires to make sure there all on all the way.

 

I just replaced all the spark plugs yesterday and the problem wire wasnt jumping today. It sounded like it was coming from the opposite side this time but it stopped before i got half way across the engine to check.
Do you think the MSD wires just aren't good for some reason? It almost seems like I should just get regular spark plug wires at this rate.

 

they may not like the coil pack, try a google on it a few different ways and see if anything comes up.

 

The noise is lifter noise. If the lifter noise only shows up when the oil pressure is showing high then you are back to a bearing issue. If you install a hand held oil pressure gage you should confirm the oil pressure spike or depending on where you hook up the oil pressure gage it may show "zero" when your indash gage shows high pressure. That would confirm 100% the bearing issue.

If the oil pressure is only spiking when you hit the throttle cold and the lifter noise is independant from that and just when the engine is cold you are in a exclusive club I like to car "everyone with a GM V6 with about 150K on it"

To be a little clearer. Seeing oil pessure jump on a high miles GM V6 when it cold is normal. They tend to run low at idle and spike the second you touch the throttle. This is most noticable before the oil warms up. GM lift tap on higher miles motors cold is very common and most likely just a small piece of dirt stuck in a lifter pump. Some STP oil cleaner, some mobil1 oil and a good filter will fix that up most of the time.

 

im thinking your last idea might clear up the situation. im going to try crabys idea on the spark too.
Ive never heard this happen on my old camaro which even had an oil leak and 185k on it. but then again, that could have been luck somehow.
but i wanted to do an oil change again soon anyhow since i have an oil cooler for it. and i always use mobile 1. so ill get some new oil, the oil cleaner, filter, and hook up the oil cooler, and see how that works as well as some regular spark plug wires to see if the wires just dont like the coil packs.
Ill let you all know what happens then.

 

I am curious, you mention seeing a plug wire issue and that a plug blew up but ou have never mention a problem that would have been caused by a plug or wire issue? When a v6 drops a cylinder (what would happen if a plug or wire failed) the whole car would shake really lack power. You never mention anything that indicated an ignition issue.

 

Thats because I didnt actually drive the car while it had the issue. It stayed in park and I only revved it to about 1800rpms and back down. The engine seemed a little off, rough idle, but i never pointed it out since I was planning on taking a video which I never got a good enough of a one to put up. Since I never drove it though, I have no idea what it would have done past that point.