hoo boy... lets see...
I'll qualify mine by saying my car is total street car. Very little racing, never seen the high side of 20 psi. Also, every time I went through it I got short blocks done by someone else, and I did the installation of heads, cam, timing chain cover, etc...
#1 - Stock engine - at 100k miles I had a shop install a new timing chain as a preventative measure. Spun a bearing when they fired it up. They didn't prime the oil pump, though I think they did pack it with vasoline. They had some other theories about why it spun, but I think it was not priming it. That lead to...
#2 - GM replacement short block (this was back when you could still get them). Mechanic installed the heads/cam/etc. Not sure what happened to this one. Seems like some kind of oil starvation problem. Went 10k miles. This one I really rev'ed up (on the street) a couple of times, I think by screwing up while manually shifting, or having it in 2nd when I thought it was in D, and each time I did it lost 5 psi of hot idle oil pressure. Then took it to the track and made a pass and it was knocking real loud on the return road. Spun a bearing again. Which lead to...
#3 - Rebuild of #2. Figured I couldn't screw it up any worse than the mechanics I had been using, so I pulled it and reassembled it myself. No racing, all street. Went about 5k miles I guess. Then gave it a good run out by my folks place, couple hundred miles away, and then watched the oil pressure slowly drop all the way back home. Dropped 10 psi I want to say over that drive. Yanked it, back to the machine shop, and he couldn't really find anything wrong with it. All new bearings, rechecked everything, gave it back to me. I bought an econo-roller from PT&E for it. Everything seemed to be fine again, although the oil pressure did drop a little bit as I drove it.
#4 - Then started hearing all the horror stories about the econo-rollers. Tore mine down to yank it out and install a flat tappet cam. Cam showed a little wear, but not much, it did no damage. Noticed though that the #1 cam bearing was pretty worn. Installed a new TA Perf cam bearing in the #1 spot during this time. Upon restart, oil pressure came back to where it had been before. Said ah-ha! I bet this is why I pulled #3 out. After this I drove the engine a good while, time-wise. No idea how many miles though. Then...
#5 - Car did sit a lot. Goes weeks, sometimes months at a time without being started. Then started driving it more. Got out on the beltway, cruising along, look down at my water temp gauge and it is pegged. Running great though, for a few minutes, then oh crap. Knocking by the time I was able to pull over safely. Still knocking after it cooled off. Teardown reveals a thermostat that had rusted shut (or at least no longer worked for some reason). Two pistons got a little too big for their britches and scored the cyl walls. Bearings all looked perfect though. Bored it out and new pistons and it runs great again!
That's my story, so far
I sure hope I don't acquire any more!
John
. Dont know how long i was running on 3 mains. It also cracked along the perimeter of the block. It had an oil leak i couldnt figure out. Lol! Both engines made over 600hp with hundreds of floggings through 3rd gear each. The one in my sig is a grenade with the pin pulled also. Neither of them had a crank failure suprisingly. Running stock cranks. Almost anytime theres headgasket failure its operator error. Not really blown up at that point either.
