I figured it's past time to change out my spark plugs that were installed back in '08. Saw some wear on one plug from the passenger bank, some brown deposits building up on passenger bank plugs too.

Old plugs that were installed by a shop in '08 were AC Delco 4355, and I was able to get some Champion RJ12YCs off EBay a while back.

Just finished installing them (1 hour just to get the rear-most plug on the driver's side , 2 hours to get them all done using hand tools..I don't miss wrenching for a living at ALL )

Anyhoo, think these plugs might be a tad too cool for surface street driving?

I'm going to break them in traveling out to a prison 75 miles away that I go to for leading a Bible study tonight, but I figured I'd ask those more knowledgeable on this fine board their opinions...I hope it doesn't break down into this

What say y'all?