I wonder if aggressive timing is part of the reason early Northstars all had premature deaths.

It's possible - I don't know much about the Northstars actually, but I did drive them as rental cars a couple of times when traveling on business. The thing is that those rental cars knocked like a bastard, even when driving pretty tame. I'm sure that when the cars were returned to the rental agency, as long as the needle pointed to "F" the companies didn't check the octane of the fuel in the tank. Most (all?) renters would just put in the cheapest crap they could to get the needle to F, instead of putting in the high-octane fuel they required...

-BC

=> only foamy oil caps or a broken headgasket? My wife's car has >80% of the time a foamy oil cap. We baught the car brand new and I also know that a foamy oil cap CAN be a sign of broken gasket. Turns out it's condensewater as she uses the car to drive only a few miles/drivecycle. In the beginning I was worried, but there's nothing going on. If I drive the car in summer to work a few times it's all gone. It's also because the valvecover and cap are of plastic and the cap is 10cm above the valve cover. With the 0W30 in it since a few weeks the mayonaise is now much thinner.
=> what you're saying it's true, but it's the financial department that decides on the cost and quality of every part.:mad:

...and the marketing department. At least the financial department cares about potential warranty, recall, and (if enough have short service life) class action lawsuit issues. The marketing department, IF they have a long view at all, cares about reputation but reputations are set in stone these days.

The poor engineering department doesn't get the involvement that they should.

Detonation and pre-ignition is what kills head gaskets, a little knock shouldn't harm anything. Have you ever taken off at a light next to a 90s ford? You'd think it was going to knock itself to death but that's just how they are. They get great economy and the bodies fall apart or the transmission dies way before the engine shows signs of fatigue.