So, Its been a while, But i finally pulled the engine apart. And found a few surprises.....
First surprise, Yes they are flat top pistons. No they are not 10:1. They are 8:1. Factory 3418919 pistons. Still is a standard 4" bore. they sit down at least .080" Makes my 125 - 135 PSI compression test make sense. I imagine this would have a hard time putting out 250 HP with that low of compression.
Second: There is evidence that all of the exhaust valves hit the pistons at some point. Maybe it had been over reved?
Third: There is a seal from a machine shop on the cylinder heads. Likely they have been rebuilt at some point. Maybe because it was over reved? Look like regular J heads with the 1.88 inlet valve. Have not been ported.
Forth: It has a Mopar windage tray.
Fifth: #7 rod is bent. I found this out whilst trying to measure how far down the pistons sit. One side was down .092 the other side of the same piston down .102
Sixth: There is some rust pitting in several cylinders, from the engine sitting. Not really a surprise though.
At this point, i don't trust any of the deck height measurements. But i do know it will likely need to be decked once i gather some new pistons and rods.
Now i need to decide whether to build it with hypereutectic , or go with some forged units.
I still toy with the idea of putting a centrifugal blower on it at some point.... So overbuilding it now would be an easy way to prep for the future.
There will be no cheap, throw rings and bearings at it anymore. It needs a major.
I'm still trying to figure out what cam was in it. I measured intake and exhaust center lines, but never measured duration, because i'm a dumbass..... There are no part numbers on the cam. There is some purple / red paint splashed on the cam, near the distributor gear, But also some white paint further up. centerlines of 107 and 115 deg. measured .324 lift, with a 1.5 rocker should be .486.
Unfortunatly that does not match any of the Mopar purple cams. Most closely matches the
280° Hydraulic: P4452992
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