Originally Posted by fantastic88
IDK, i'd be curious to see how an LT1 is a much stronger motor.
The LT1 is no better or worse than the rest of the SBC family, nor any more durable than the 3800. A coolant leak into the heads or block is bad. It doesn't matter what motor you are working with.
The real LT1 killer is the leak at the Water Pump drive shaft, since it tends to wet down the Opti-Spark distributor and kill it. 2nd place goes to the rear intake to block seal, which gives out and the motor starts bleeding oil out the back. 3rd place is the cheap freeze plugs put in at the factory, which are thin and rust through, leading to a coolant leak in difficult to reach places. The basic rotating assembly and block are pretty good stuff. The heads have the usual valve seal problems that all SBC'* seem to share, but are otherwise sound. The head gasket is good, but like any motor with aluminium heads on an iron block, it doesn't take overheating well.
Last, are the actual drivers/owners/mechanics. There are less LT1'* in total and the people who own them trash the livin heck out of them. (or start doing mods, dickin around, etc.) which leads to a higher incidence of failures. Look at it this way..how many 3800'* get the hard use typical of the owners on this list? It'* probably less than 1% of all the 3800'* in service. The LT1 went into cars that, by their nature, are going to get abused a lot more...sports cars, taxi'*, police cars, etc.