[LX5liter]

I think my engine's on its way out. When I start it there is a knocking sound on the drivers side. It's pretty loud until it warms up then it goes almost totally away. I'm thinking a scuffed or broken piston, or maybe something as simple as a bad lifter. The middle two cylinders are running about 100 degrees hotter than the other 6, so I'm thinking that's where the problem is. Any other thoughts? I haven't got around to a compression test yet, but I will do that asap.
The engine does have over 160,000km (100,000 miles) on it, and I've been beating on it at the track pretty good this year (w/ 10#'s of boost) so the engine doesn't owe me a darn thing, I was just hoping it would get me through two more races. I will be building a 331 for it over the winter. Should I get a pool going to see how long it will last? 1 race, 2 races, or less?