Looks like I really should have rebuilt my 4-53T. I started having blowby issues when under 30 psi of boost. I got 1000 kms on the engine and went out to work the rings back in. Well 5 minutes into the 8% grade the engine shit itself, broke the liner in cylinder #2. It was running well, then the temp started to climb rapidly, with a haze out the exhaust. When the temp hit 190-195 I started to back off the throttle, but too late. Cylinder #2 failed and by the time I could get to a safe pull off the temp was 200-205. This isn't hot, but for a Detroit it's about as hot as you ever want to get. It drank 2 gallons of coolant in a very short period of time. I started to pull the engine apart to see what caused it and I wasn't very happy. All the liners are worn out, signs of rusting from years out in the Florida weather before some smart person decided to get it running and sell it off. Anyway I can only blame myself as I certainly know better, but was fooled by how well it ran. Looks like I can now build it up with better parts and make some more power. Here's some pictures and a tube video. To be continued.