Disassembly of a 69 Z/28 DZ Three Oh Blew Engine

[SuperNovaSS]

I realize I have not been sharing here as much as I used to and am going to try to start posting more often.

I buy complete muscle car engines that have been sitting dormant for long periods of time pretty often. Sometimes they are engines that were pulled out of running cars or boats, others were pulled from non running cars, and the gambles were pulled to to sudden death. Sudden death is the case with the engine I am sharing with you today.

This is a 69 Camaro Z/28 "DZ 302" engine that was pulled from a 69 Z/28 after some enthusiastic tuning sessions. As you can see by the oil pan, the high revving mouse engine was likely pushed a bit further than designed. This was the cause of death for many early Z/28 engines. Like a kid eating cake, the engine keeps asking for more but eventually it is going to have to puke!

This engine was in a true 69 Z/28 but was not the VIN matching engine for the car. After "tuning" this engine, the owner decided to build a new engine for the car from scratch, taking items off this engine like the pulleys, etc. This engine was put on a dolly and put in the corner of the garage without ever being opened up to evaluate the damage. The owner decided to sell the engine recently and I could not resist seeing what was inside.






















Looking at the numbers, the engine began life as a true DZ 302 and had likely been tinkered with in the past. I say this because the block has a March 69 casting date and assembly code but the heads are dated August 1968. I imagine the top end was original to the Z/28 the engine was installed in and the shortblock was replaced at some point. That is just an assumption though, the heads on the engine could be off of anything and could even have the smaller 1.94/1.50 valves. It is reasonable to assume if the engine has been apart than it has likely been bored and possibly had other work done. Other evidence that this engine has been apart include a later model timing cover and later model valve covers with drippers(69 were non dripper).

The only way to find out is to dig in and get dirty........