Knock, Knock, oh #%@$

[6APPEAL]

00 GSE supercharged, all stock, 98K. It's been a good car, but a PITA at times. Replace LIM gaskets about a month ago. Still had a noisy lifter for about a week, but it quieten down after that. The car has been running great, more power, better mpg, then.....
Last night the wife calls me after she gets home. On the way home the car starts "sounding like there's a chipmunk under the hood" (her words). Ran rough for a minute or two (almost died once), then ran fine, just noisey. No SES light, nothing. I get home and crank the car. Runs perfect at idle, no noise at all, sounds great. Give it some gas and it starts knocking (rpm related, faster rev, faster knock). Of course it's night and I can't really see s@#%, even with a flashlight, plus the car is still hot. Go in and search the site. Find a couple of videos of rod knock that sound like the wife's car. But, not the same as the videos or the same as when I spun a bearing in one of my turbo cars, they knock(ed) all the time, unlike the wife's car.

Question is, could it be a spun bearing (rod knock) or perhaps the lifter that was noisey colapsed (runs smooth at idle?)? I'l get home and drain the oil, change the filter, put some Lucus oil treatment in with fresh oil, check the old oil and filter for metal and retry running the car.

Opinions???? Don't say "used" motor. New GM longblock $3100 , is a 9 year old car worth it?
John

 

[6APPEAL]

Just talked to the Machinist I use, who happens to own one of these cars along with a couple of 86/87 turbo cars. He suspects that one of the bearing shells rotated under the other. At idle there is still enough oil pressure to keep the rod off the crank journal, so no noise at idle. But, as the rpm's go up, the oil film cannot keep the rod off the crank, so rod knock noise. He said he had seen this before and to drop the pan and start wiggling rods to find the bad one. He also said that when this happens, you could get piston to head contact.

So most likely, I'll be prospecting while draining the pan. I don't want to attempt to remove the pan with the engine still in the car, too much of a PITA according to the posts I've read on the RegalGS board.
John